Podcasts about cxcr4

Dr. Angela Fleischman and Dr. Gabriella Hobbs discussed two intriguing abstracts presented at the ASH 2024 Annual Meeting about emerging treatments for myelofibrosis. The first study, led by Dr. Lucia Massarova, explored the safety and preliminary efficacy of cord blood-derived CXCR4-enriched T-regulatory cells in patients with suboptimal response to ruxolitinib, showing minimal adverse events and potential improvements in hemoglobin, spleen size, and symptoms. The second study evaluated nuvusertib (TP3654), a selective PIM1 kinase inhibitor, in patients with relapsed/refractory myelofibrosis, demonstrating stable hemoglobin and platelet levels, symptom and spleen volume improvement, and preliminary evidence of fibrosis and cytokine response.

What are topical steroids? Often prescribed for chronic skin conditions, I'll bet you've probably used them at some point during your treatment.Sure, they work quickly, but are they without side effects? To answer that question, we need to talk about glucocorticoids, which are hormones naturally produced by the adrenal glands as part of the stress response.Topical steroids fall under the glucocorticoids category, and due to those who've experienced something called topical steroid withdrawal, some people are described by physicians as “steroid phobic.”While there are serious downsides, glucocorticoids can have some incredible anti-inflammatory effects on various health conditions. That's why it's crucial for us to have a nuanced conversation about this!Dr. Luis Franco joins me to discuss everything you've wanted to know about topical steroids, types of glucocorticoids, and concerns about side effects from using topical steroids.Dr. Luis Franco is a Tenure-Track Investigator at the National Institute of Musculoskeletal and Skin Diseases (NIAMS). He was born in Colombia and grew up between Colombia, Brazil, Mexico, and the United States. He attended medical school in Colombia before returning to the United States, initially as a postdoctoral fellow at Duke University. Dr. Franco attended Baylor College of Medicine for specialty training in internal medicine and medical genetics. In 2014, he moved to the National Institute of Health (NIH).In This Episode:What are topical steroids versus glucocorticoids?Are topical steroids + glucocorticoids bad?Cortisone vs cortisol (and glucocorticoids examples by name)Side effects of glucocorticoidsWhat is topical steroid withdrawal?How glucocorticoids modulate your immune systemQuotes“Glucocorticoids exist naturally. They are hormones that are produced by our bodies. And they're produced by this very particular gland that's above our kidneys, that's called the adrenal gland or the suprarenal gland. And so our adrenal glands produce these chemicals called glucocorticoids. And those chemicals have many, many roles in biology and the one that is sort of best understood is that they are part of the stress response.”“I think the side effects that are important to know for topical glucocorticoids are one, something called skin atrophy, which is kind of a thinning of the skin that people notice when they've been applying glucocorticoids for a long time. Some people also notice little, kind of red, blood vessels that come up. These are called telangiectasias. These are like reddish blood vessels that become very visible on the skin of people who have used topical glucocorticoids.”LinksFind Dr. Franco onlineHealthy Skin Show ep. 344: NEW RESEARCH On Topical Steroid Withdrawal Symptoms + TSW Red Skin TriggerTopical Steroids Potency ChartImmune regulation by glucocorticoids can be linked to cell type–dependent transcriptional responsesGlucocorticoid-induced eosinopenia results from CXCR4-dependent bone marrow migration

Pentixapharm is a clinical-stage radiopharmaceutical development company targeting a range of diseases. While it is currently owned by the Eckert & Ziegler Group, it will soon be spun off as a separate company. Pentixapharm's clinical pipeline includes PENTIXATHER, am Yttrium-90 based therapeutic against CNS lymphoma, and PENTIXAFOR, a Gallium-68 based companion diagnostic. Additionally, PENTIXAFOR is being developed as a diagnostic tool for primary aldosteronism (PA), a significant cause of hypertension.Recently, the company announced the acquisition of the target discovery business of Glycotope.The deal includes a portfolio of preclinical antibodies against multiple oncology targets that can be developed into radiopharmaceuticals. It also includes Glycotope's laboratories, cell banks, tumor target data base, and the equipment needed to exploit the discovery platform, along with a range of patents, licenses, and other tangible assets. This week, we had a conversation with Andreas Eckert, founder and chairman of the supervisory board at Pentixapharm.00:57-03:07: About the Pentixapharm spinout03:07-05:19: What is Pentixapharm's pipeline?05:19-06:01: What is the CXCR4 ligand approach?06:01-08:51: What are the development plans for tackling primary aldosteronism? 08:51-10:28: Is the process fast, and what about cost?10:28-11:47: The bigger economic picture11:47-14:12: About Glycotope14:12-14:44: How synergistic are Pentixapharm and Glycotope?14:44-15:32: Is the entire company being acquired?15:32-16:27: Will outsourcing still be important to the company?16:27-17:55: What does the future hold for Pentixapharm?Interested in being a sponsor of an episode of our podcast? Discover how you can get involved here! Stay updated by subscribing to our newsletter

In this week's episode we'll discuss the mutational and transcriptional landscape of pediatric BCP lymphoblastic leukemia; learn more about the role of platelet-derived TGF-β1 in immune thrombocytopenia; and discuss the findings from a phase 3 trial of mavorixafor in WHIM syndrome.Featured Articles:Mutational and transcriptional landscape of pediatric B-cell precursor lymphoblastic lymphoma Platelet-derived TGF-β1 induces functional reprogramming of myeloid-derived suppressor cells in immune thrombocytopenia Phase 3 randomized trial of mavorixafor, CXCR4 antagonist, in WHIM syndrome 

CME credits: 1.00 Valid until: 29-05-2025 Claim your CME credit at https://reachmd.com/programs/cme/whim-syndrome-and-cxcr4-variants-new-insights-into-cellular-changes-that-can-impact-patient-treatment-plans/24548/ WHIM syndrome is a rare, inherited, combined immunodeficiency disease caused by reduced mobilization and trafficking of white blood cells from the bone marrow due to over-signaling of the CXCR4/CXCL12 pathway. WHIM syndrome is named for its four common clinical findings. The diagnostic challenges arise because not all symptoms are required for a diagnosis and all of them do not appear at the same time. Patients have deficient blood levels of neutrophils (neutropenia) and lymphocytes (lymphopenia), which results in frequent, recurrent infections. Affected individuals are particularly susceptible to human papillomavirus (HPV), which can cause skin and genital warts and potentially lead to certain types of cancer. Our program goal is to identify risk factors associated with WHIM syndrome, focusing on making an earlier diagnosis that can impact long-term outcomes, timely treatment options and ultimately improved quality of life for patients.

In this week's episode we'll discuss the findings from a study exploring the combination of concurrent pembrolizumab, adriamycin, vinblastine, and dacarbazine in newly diagnosed classical Hodgkin lymphoma, learn more about the effects of targeting the CD40/CD40-ligand axis in Waldenström Macroglobulinemia, and review the findings from a study aimed at improving the bone marrow homing of CAR-cytokine induced killer cells in AML.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.04.04.535566v1?rss=1 Authors: Aguilar-Bravo, B., Arino, S., Blaya, D., Pose, E., Martinez Garcia de la Torre, R. A., Latasa, M. U., Martinez-Sanchez, C., Zanatto, L., Sererols-Vinas, L., Cantallops, P., Affo, S., Coll, M., Thillen, X., Dubuquoy, L., Avila, M. A., Argemi, J. M., Lamas Paz, A., Nevzorova, Y. A., Cubero, J., Bataller, R., Lozano, J. J., Gines, P., Mathurin, P., Sancho-Bru, P. Abstract: Background and Aims: Loss of hepatocyte identity is associated with impaired liver function in alcohol-related hepatitis (AH). In this context, hepatocyte dedifferentiation gives rise to cells with a hepatobiliary (HB) phenotype expressing biliary and hepatocytes markers and showing immature features. However, the mechanisms and the impact of hepatocyte dedifferentiation in liver disease are poorly understood. Methods: HB cells and ductular reaction (DR) cells were quantified and microdissected from liver biopsies from patients with alcohol-related liver disease (ALD). Hepatocyte-specific overexpression or deletion of CXCR4, and CXCR4 pharmacological inhibition were assessed in mouse liver injury. Patient-derived and mouse organoids were generated to assess plasticity. Results: Here we show that HB and DR cells are increased in patients with decompensated cirrhosis and AH, but only HB cells correlate with poor liver function and patients outcome. Transcriptomic profiling of HB cells revealed the expression of biliary-specific genes and a mild reduction of hepatocyte metabolism. Functional analysis identified pathways involved in hepatocyte reprogramming, inflammation, stemness and cancer gene programs. CXCR4 pathway was highly enriched in HB cells, and correlated with disease severity and hepatocyte dedifferentiation. In vitro, CXCR4 was associated with biliary phenotype and loss of hepatocyte features. Liver overexpression of CXCR4 in chronic liver injury decreased hepatocyte specific gene expression profile and promoted liver injury. CXCR4 deletion or its pharmacological inhibition ameliorated hepatocyte dedifferentiation and reduced DR and fibrosis progression. Conclusions: This study shows the association of hepatocyte dedifferentiation with disease progression and poor outcome in AH. Moreover, the transcriptomic profiling of HB cells revealed CXCR4 as a new driver of hepatocyte-to-biliary reprogramming and as a potential therapeutic target to halt hepatocyte dedifferentiation in AH. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.02.28.530397v1?rss=1 Authors: Verma, A., Asthana, S., Saini, D. K., Ayappa, K. G. Abstract: CXCR4 is a G-protein coupled receptor which mediates signalling for diverse functions such as cell proliferation and migration, hematopoiesis and plays a role in embryogenesis and development. Signal transduction occurs primarily through transmembrane helices that function in the multicomponent lipid environment of the plasma membrane. Elevated levels of plasma membrane oxysterols occur in cardiovascular and metabolic disorders, physiological stress and inflammatory conditions. We use experimental and simulation approaches to study the impact of oxysterol chemistry and composition on CXCL12-mediated CXCR4 signalling. Experiments on HeLa cells show a pronounced decrease in calcium oscillation response for the tail oxidized sterols in comparison with the ring oxidized sterols with 22(R) hydroxycholesterol showing a near complete loss of signalling followed by 27-hydroxycholesterol and 25-hydroxycholesterol. All-atom molecular dynamics simulations reveal that tail oxidized, 27-hydroxycholesterol, displaces cholesterol and ubiquitously binds to several critical signalling residues, as well as the dimer interface. Enhanced 27-hydroxycholesterol binding alters CXCR4 residue conformations, disrupts the toggle switch and induces secondary structure changes at both N and C termini. Our study provides a molecular view of the observed mitigated CXCR4 signalling in the presence of oxysterols revealing that disruption of cholesterol-protein interactions, important for regulating the active state, is a key factor in the loss of CXCR4 signalling. Additionally, a signalling class switching from Gi to Gs as revealed by increased CREB and ERK phosphorylation is observed in the experiments. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.02.21.529372v1?rss=1 Authors: Han, Y., Liu, Y., Tian, X., Zhang, X., Liu, D., Yan, C. Abstract: Aortic aneurysm (AA) is a potentially fatal disease with the possibility of rupture, causing high mortality rates with no effective drugs for the treatment of AA. The mechanism of AA, as well as its therapeutic potential to inhibit aneurysm expansion, has been minimally explored. Small non-coding RNA (miRNAs and miRs) is emerging as a new fundamental regulator of gene expression. This study aimed to explore the role and mechanism of miR-193a-5p in abdominal aortic aneurysms (AAA). In AAA vascular tissue and Angiotensin II (Ang II)-treated vascular smooth muscle cells (VSMCs), the expression of miR-193a-5 was determined using real-time quantitative PCR (RT-qPCR). Western blotting was used to detect the effects of miR-193a-5p on PCNA, CCND1, CCNE1, and CXCR4. To detect the effect of miR-193a-5p on the proliferation and migration of VSMCs, CCK-8, and EdU immunostaining, flow cytometry, wound healing, and Transwell Chamber analysis were performed. In vitro results suggest that overexpression of miR-193a-5p inhibited the proliferation and migration of VSMCs, and its inhibition aggravated their proliferation and migration. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

1:25 Labiotech.eu news3:02 GPCR Therapeutics22:16 eClinical Solutions31:04 Orbsen TherapeuticsThis week, our guests are Katrina Rice, chief delivery officer, biometrics services at eClinical Solutions; Pina Cardarelli, president and CSO of GPCR Therapeutics; and Larry A Couture, CEO of Orbsen Therapeutics.GPCR Therapeutics launches multiple myeloma trial GPCR Therapeutics, Inc., a drug discovery company targeting G Protein Coupled Receptors (GPCR) pairs, recently started its phase 2 trial in the U.S. for its lead small molecule asset, GPC-100.  GPC-100 targets CXCR4, one of the most prevalent chemokine GPCRs overexpressed in more than 23 cancers.This randomized, open-label phase 2 study assesses the efficacy of GPC-100 and propranolol, with and without granulocyte colony-stimulating factor (G-CSF) for the mobilization of stem cells in patients with multiple myeloma undergoing autologous stem cell transplant. Survey looks at biotech challengeseClinical Solutions, a provider of digital clinical software and biometrics services, has published a survey detailing insights from 60 biopharmaceutical clinical operations and biometrics professionals on the most pressing trends, challenges, and opportunities that are shaping the clinical data landscape. Some key takeaways include: 64% of respondents are leveraging 6 or more external data sources; harnessing automation is the top overarching industry priority for more than one-third (36%) of respondents; and speed (30%) and quality (30%) are reported as the largest pain points for electronic data capture (EDC) database build.Orbsen TherapeuticsOrbsen Therapeutics is an Irish-headquartered company working in stromal cell immunotherapy. The company has leveraged its proprietary technology platform, which is based on highly purified stromal stem cells, to establish a specific portfolio of early-stage product candidates. Orbsen's allogeneic or 'off-the-shelf' cell product candidates target significantly advanced stages of diseases where there are high unmet medical needs, including moderate-severe acute respiratory distress syndrome (ARDS), autoimmune disease and Stage 3 DKD.

Please join authors Loren Field and Sean Reuter, as well as Associate Editor Thomas Eschenhagen as they discuss the article "Cardiac Troponin I-Interacting Kinase Affects Cardiomyocyte S-Phase Activity But Not Cardiomyocyte Proliferation." Dr. Greg Hundley: Welcome listeners, to this January 10th issue of Circulation on the Run, and I am Dr. Greg Hundley, associate editor, director of the Pauley Heart Center at VCU Health in Richmond, Virginia. Dr. Peder Myhre: I am Dr. Peder Myhre from Akershus University Hospital and University of Oslo in Norway. Dr. Greg Hundley: Well, listeners, this week's feature discussion delves into the world of preclinical science and evaluates cardiac troponin I and its impact on S phase activity in cardiomyocytes, and does that relate to cardiomyocyte proliferation. But before we get to that, how about we grab a cup of coffee and Peder and I will work through some of the other articles in the issue. Peder, how about this week I go first? Dr. Peder Myhre: Go ahead, Greg. Dr. Greg Hundley: Right. So Peder, this first study evaluated whether the burden of positive coronary artery calcification on cardiovascular disease differed by multidimensional individual characteristics, and so the investigators led by Dr. Kosuke Inoue from Kyoto University sought to investigate the heterogeneity in the association between positive coronary artery calcium and incident cardiovascular disease. And so Peder, to examine this question, the authors implemented a cohort study design that included adults aged greater than 45 years, free of cardiovascular disease, from the Multi-Ethnic Study of Atherosclerosis, or MESA, and after propensity score matching in a one-to-one ratio, they applied a machine learning causal forest model to, first, evaluate the heterogeneity in the association between positive coronary artery calcium and incident cardiovascular disease and then, second, to predict the increase in cardiovascular disease risk at 10 years when the coronary artery calcium score was greater than zero, so versus is it zero at all at the individual level? Dr. Peder Myhre: Oh, Greg, that is so cool, so using machine learning for coronary artery calcium and risk prediction, I'm very excited. What did they find? Dr. Greg Hundley: Right, Peder, so the expected increases in cardiovascular disease risk when the coronary artery calcium score was greater than zero were heterogeneous across individuals. Moreover, nearly 70% of people with low atherosclerotic cardiovascular disease risk showed a large increase in cardiovascular disease risk when the coronary calcium score was greater than zero, highlighting the need for coronary artery calcium screening among such low-risk individuals. And Peder, future studies are really needed to assess whether targeting individuals for coronary artery calcium measurements based on not only the absolute ASCVD risk, but also the expected increase in CVD risk when a CAC score is greater than zero and whether that improves overall assessment of cardiovascular outcomes. Dr. Peder Myhre: Wow, that is so clinically relevant and very interesting. And we're actually going to stay clinically relevant with the next paper which is about anti-platelet therapy after PCI. And this paper describes the long-term results of the HOST-EXAM trial. To remind you, Greg, the HOST-EXAM trial was an investigator-initiated prospective, randomized, open label, multicenter trial done at 37 sites in Korea. They enrolled patients who had undergone PCI with DES and maintained dual anti-platelet therapy without any clinical event for a mean 12 months and then they were randomized one to-one to either clopidogrel, 75 milligrams once daily, or aspirin, 100 milligram once daily. The primary results of this trial was published in Lancet in 2021 and showed superiority of clopidogrel over aspirin in prevention of the composite of MACE and major bleeding during 24 months of followup. And then, through the current paper, this describes the results of the post trial extended followup of about five years. Dr. Greg Hundley: Very nice, Peder, so aspirin versus clopidogrel and looking at the maintenance of that monotherapy and cardiovascular outcomes. Wow, so what did they find? Dr. Peder Myhre: Yeah, Greg. They, in this extended followup study, had a total of 5.8 years median followup, and the primary endpoint occurred in 12.8% in the clopidogrel group versus 16.9% in the aspirin group, and that has a range of 0.74 with a 95% conference interval ranging from 0.63 to 0.86. So also the clopidogrel group had lower risk of the secondary thrombotic endpoint and the secondary bleeding endpoint while there was no significant difference in the incident on all caused death. So Greg, to conclude, these very interesting results from the primary analysis of the HOST-EXAM trial was consistent through the longer followup, and this support the use of clopidogrel over aspirin monotherapy from 12 months onwards after PCI. Dr. Greg Hundley: Very nice Peder, beautiful description and sounds like long-term clopidogrel use over aspirin was quite beneficial. Well, the next study comes to us from the world of preclinical science, and it is from the investigative group led by Dr. Yunzeng Zou from Shanghai Institute of Cardiovascular Diseases and the Zhongshan Hospital and Fudan University. Peder, the study pertains to diabetes. So diabetic heart dysfunction is a common complication of diabetes mellitus and cell death is a core event that leads to diabetic heart dysfunction. However, the time sequence of cell death pathways and the precise intervening time of particular cell death type remained largely unknown in diabetic hearts. And so, Peder, this study aimed to identify the particular cell death type that is responsible for diabetic heart dysfunction and propose a promising therapeutic strategy by intervening in this cell death pathway. Dr. Peder Myhre: Wow, Greg, that is really interesting. Heart dysfunction in diabetes is something that we really have to learn more about and I'm so excited to hear what these authors found, Greg. Dr. Greg Hundley: Right. So first, Peder, the authors identified necroptosis as the predominant cell death type at later stages in the diabetic heart. And then second, Peder, the CB2 receptor, and we'll call that CB2-R, recruits transcription factor Bach2 to repress necroptosis and protects against diabetic heart injury while hyperglycemia and MLKL in turn phosphorylates CB2-R to promote ubiquitous dependent degradation of CB2-R, thus forming a CB2-R centric feedback loop of necroptosis. And finally, Peder, cardiac CB2-R or Bach2 expression negatively correlates with both MLKL 10 expression and the extent of diabetic heart injuries in humans. And so the clinical implications of these findings, Peder, are that the CB2-R centric necrotic loop represents a promising target for the clinical treatment of diabetic heart injuries. Dr. Peder Myhre: So Greg, this paper that comes to us from corresponding author Amanda Paluch from University of Massachusetts Amherst, is a meta-analysis of eight prospective studies with device measured steps including more than 20,000 adults who were followed for CVD events. And the mean age of participants in this study was 63 years and 52% were women. And the participants were followed for a median of 6.2 years and 1,523 cardiovascular events occurred. So first, Greg, there was a significant difference in the association of steps per day in cardiovascular disease between older, that is greater or equal to 60 years, and younger, that is less than 60 years adults. So for older adults that has the ratio for cardiovascular disease using Q1 as reference was 0.80 for Q2, 0.62 for Q3, and 0.51 for Q4. And for younger adults that has ratio for cardiovascular disease using Q1 as reference was 0.79 for Q2, 0.90 for Q3, and 0.95 for Q4. And in the paper, Greg, there are some beautiful, restricted cubic lines that really illustrate the association between daily steps and the risk of cardiovascular disease among older adults and in younger adults. So the authors conclude that for older adults taking more daily steps is associated with a progressively lower risk of cardiovascular disease. And monitoring and promoting steps per day is a simple metric for clinician patient communication and population health to reduce the risk of cardiovascular disease. Dr. Greg Hundley: Well, Peder, we've got some other very interesting articles in this issue and how about we dive into that mail bag and discuss a few of those. So I'll go first. The first is a Perspective piece by Professor Powell-Wiley entitled “Centering Patient Voices through Community Engagement in Cardiovascular Research.” A very important topic where can those in the community actually help us design meaningful outcomes for our research initiatives? And next Peder, there is a Research Letter from Professor Evans entitled “Increasing Mononuclear deployed Cardiomyocytes by Loss of E2F7/8, and does that fail to improve cardiac regeneration post myocardial infarction?” Dr. Peder Myhre: Thanks, Greg. We also have an ECG Challenge by Dr. Li entitled, “What Is The Truth Behind Abnormal ECG Changes?” And this is describing a very rare and interesting cause of ST segment elevation. I recommend everyone to read that case. We also have our own Nick Murphy who gives us the Highlights from the Circulation Family of Journals where he summarizes five papers from the Circulation subspecialty journals. First, the experience with a novel visually assisted ablation catheter is reported in circulation A and E. The impact of various exercise training approaches on skeletal muscle in heart failure with preserved the F is presented in circulation heart failure. Gaps in heart failure treatment over a decade are reported in circulation cardiovascular quality and outcomes, and the associations of machine learning approaches to plaque morphology from coronary CTA with ischemia are reported in circulation cardiovascular imaging. And finally, Greg, an observational study of left main PCI at sites with and without surgical backup is reported in circulation cardiovascular interventions. Let's go on to the feature paper today describing the cardiac troponin I interacting kinase and the impact on cardiomyocyte S phase activity. Dr. Greg Hundley: Great, let's go. Welcome listeners to this January 10th feature discussion. Very interesting today as we are going to delve into the world of preclinical science. And we have with us today Dr. Loren Field and Dr. Sean Reuter from University of Indiana in Indianapolis, Indiana. And our own associate editor, Dr. Thomas Eschenhagen from University Medical Center of Hamburg in Hamburg, Germany. Welcome gentlemen. Well, Loren, we're going to start with you. Can you describe for us some of the background information that went into the preparation of your study, and what was the hypothesis that you wanted to address? Dr. Loren Field: Sure. This study actually came about in a rather roundabout fashion. We were doing a study with Kai Wollert in Hanover, Germany, where we were looking at the impact of a CXCR4 antagonist, which is used to mobilize stem cells from the bone marrow. And we had sent our mice over to Kai's lab and we have a mouse model that allows us to track S phase activity in cardiac myocytes, so these are cells are starting to replicate. And Kai crossed them into a different genetic background. And when he sent the mice back to us to analyze the hearts, we observed that we saw things that we never saw before in our experiments here. His injury model was different than ours and now the mouse also had a genetic background, so we had to spend about a year to figure out if it was the injury model or the background. It turned out to be the genetic background, and the phenotype was these mice had about a 15-fold elevated level of cell cycle reentry. So then it became a relatively simple genetics game where we took the progenitor mice, made F1 animals, looked for the phenotype, did backcross animals, and basically identified the gene responsible for the phenotype. Dr. Greg Hundley: Very nice. And so in this study moving forward, what hypothesis did you want to address? Dr. Loren Field: Well, the main hypothesis was to figure out what the gene was and then secondarily to figure out the degree of cell cycle progression. When the cell is proliferating, the first task is to replicate its genome, which is S phase activity that's followed by the nuclei dividing and then finally by the cell itself becoming two cells. So our task was to identify, first, the gene and secondly, how far through the cell cycles the cells progressed. Dr. Greg Hundley: Very nice. And how did you construct your experiment? Dr. Loren Field: It was, again, very straightforward. It was simply setting up the appropriate genetic crosses to produce the animals. For the past 10, 15 years, we've been developing a computer assisted assay that allows us to identify the anatomical position of S phase positive cardiac myocytes in sections of the heart. And basically, we apply that program to the different genetic backgrounds and after that it's a ball of mapping studies, QTL mapping. Dr. Greg Hundley: So really mechanistic understanding. Well listeners, we're next going to turn to Sean, and Sean, can you describe for us your study results? Dr. Sean Reuter: Yes, as Loren stated, we saw a 15-fold increase in the S phase activity within the remote zone. Now we partition the heart in three different zones after injury, so the scar, the border zone, and then the remote zone or injury. And as Loren stated, we saw a 15-fold increase in the S phase activity, cell cycle activity, in the remote zone. And it's only because we have this system in hand that we can anatomically map the S phase activity within the heart that we were able to detect and also quantify this. And I think that's the reason we discovered this particular phenotype. But in addition to that, we performed RNA-seq or Exome sequencing and discovered that TNNI3K was the responsible gene for elevated S phase activity within the remote zone and border zone, but interestingly not in the scar. Dr. Greg Hundley: Very interesting, Sean, and so describe for us the importance of the TNNI3K and its relationship to this S phase. Dr. Sean Reuter: Sure. This particular gene was first discovered around 2000, and it's been studied for a while now, but the targets of this kinase specifically expressed in the heart, and it does get elevated after injury, but the actual targets are not well described or well known. It's believed that it phosphorylates some mild filament fibers and structural proteins, but the actual mechanism and the consequence of this is not known. So when we saw this in the remote zone, the elevated S phase, our current theory is that we believe that it's probably increasing oxidative stress that would basically further out from the at-risk zone or the border zone and then it now is in the remote zone. So we think it's just causing the heart, a pathological area of the heart, basically to expand. And so that's our current theory. Other groups have published on the oxidative stress in over expression of TNNI3K as well. Dr. Greg Hundley: Very nice. Well listeners, next we are going to turn to our associate editor, Thomas many articles come your way and come across your desk. What attracted you to this particular article, and how do we put its results really in the context of cardiac regeneration? Dr. Thomas Eschenhagen: Indeed, there were several arguments. It's a cool paper and the whole field is still very important. As probably most of you know, the field have a rough ride over the last 20 years, went up and down, lots of bad findings. And in the end it turns out that we are there where we have been 20 years ago, the mammalian heart essentially doesn't regenerate. So anything which would improve that would be of very major importance. Why is it a good paper? Because it starts from a very clear finding, one mouse, which looks like strongly regenerating after MI, another mouse line, which doesn't. And so by applying, let's say, classical genetic, very stringent methodology, Loren Field and his group identified this troponin I kinase to be the culprit. And they also proved it, because putting it back in the strain with a low, so-called, regeneration brought it back to the other level. So it's a very clear, nice methodology. And finally, it's also a bit provocative because others in a very prominent paper, actually, have shown that this kinase... Or they concluded more or less just the opposite. The reason for the discrepancy is not quite clear and I was very happy to learn that the two groups actually discussed about it. So it's not just a bad controversy, but something which brings forward science. And finally, I think something we didn't talk about yet today, what I particularly liked, maybe the most, on this paper is that this group didn't stop at the point of DNA synthesis. Everybody else would've probably said, "Okay, here we are, one regenerate the other doesn't." But in the very important extra finding of this paper is that this is just increased DNA synthesis and not more myocytes. And this distinction is so critical to the field because people forget that adult mammalian cardiomyocytes often have several nuclei and individual nuclei have more than one set of chromosomes, so this polyploid. And so if you see DNA synthesis like in this paper, it doesn't necessarily mean more myocytes. And actually here it was shown that it is not more myocytes but more polyploidization and making this difference so clear, I think it's a very important contribution to the field. Dr. Greg Hundley: Very nice. Well, listeners, we're going to turn back to each of our guests today and we'll start with you Loren. Based on your results, what do you see as the next study moving forward in this sphere of research? Dr. Loren Field: I think these results made me appreciate for the first time that the intrinsic level of cell cycle reentry, that's just the S phase, not the cell division, is actually much higher than I had thought previously. And this was because we just fortuitously, or I guess anti-fortuitously, we're using a strain that had low levels of S phase induction. If you calculate the turnover, if every nucleus that it synthesized DNA actually went on to have that cell divide, you could replace a 50% loss of myocytes over the course of about 550 days, give or take. And to me, that's actually telling me that if we could push those cells from just being polypoid, as Thomas was saying, to actually go through cytokinesis, there would be enough intrinsic activity to go forward. So this really tells me that what we should be focusing on is now not trying to induce cell cycle, but to allow the cells that are entering the cell cycle to actually progress through it. Dr. Greg Hundley: Very nice. And Sean? Dr. Sean Reuter: Yes, well, echoing Loren's point there, it's really not necessarily cell cycle induction, it's cell cycle completion to the cytokinetic fate. And that's the key. If we can get to that point, if we can figure out the mechanism to get to that point, then we have a wonderful discovery. However, we're not quite there yet, but we hope to be. Dr. Greg Hundley: And Thomas. Dr. Thomas Eschenhagen: Well, nothing to add really from my side, except that I would like to know what this Troponin I kinase does, because that is somehow still a missing link. How does this kinase lead to more DNA synthesis or the initiation of cell cycling? That would be an important finding and I'm sure there will be more research going on. Particularly also, to solve this discrepancy, I mean, there must be something in it and we don't quite yet know how, but I think we are in a good way. I'm sure there will be papers showing that soon. So I think that's, again, a very good start for this discussion. Dr. Greg Hundley: Well, listeners, we want to thank Dr. Loren Field, Dr. Sean Reuter and Dr. Thomas Eschenhagen for bringing us this really informative study in mammalian myocellular regeneration, highlighting that the level of cardiomyocyte cell cycle reentry in hearts expressing TNNI3 kinase would lead to significant regenerative growth if each cardiomyocyte exhibiting S phase activity was able to progress through cytokinesis. And this in turn suggests that identification of factors which facilitate cardiomyocyte cell cycle progression beyond S phase will be key to unlocking the intrinsic regenerative capacity of the heart. Well, on behalf of Carolyn, Peder and myself, we want to wish you a great week and we will catch you next week on the run. This program is copyright of the American Heart Association 2023. The opinions expressed by speakers in this podcast are their own and not necessarily those of the editors or of the American Heart Association. For more, please visit ahajournals.org.

References Dr Guerra's membrane immune synapse lectures Al-Aghbar, M.A., Jainarayanan, A.K., Dustin, M.L. et al. The interplay between membrane topology and mechanical forces in regulating T cell receptor activity. CommunBiol 5, 40 (2022). https://doi.org/10.1038/s42003-021-02995-1 Dinkel BA, Kremer KN, Rollins MR, Medlyn MJ, Hedin KE. GRK2 mediates TCR-induced transactivation of CXCR4 and TCR-CXCR4 complex formation that drives PI3Kγ/PREX1 signaling and T cell cytokine secretion. J Biol Chem. 2018 Sep 7;293(36):14022-14039. doi: 10.1074/jbc.RA118.003097. Epub 2018 Jul 17. PMID: 30018141; --- Send in a voice message: https://anchor.fm/dr-daniel-j-guerra/message

Paula Ragan is the CEO and President of X4 Pharmaceuticals, which focuses on the rare disease WHIM Syndrome. Patients have a deficiency in their immune system, and as a result, this diminishes their ability to fight chronic infections, and they have a higher risk for severe cancers. Paula explains, "If one thinks about doing the right test, it's easy to diagnose, and the right test is doing genetic sequencing. There are commercially available panels, so it exists for the patient and physician communities. The current challenge is getting the physicians to recognize the test is needed. And then to also enable payment. X4 has done a great job in providing free testing through our PATH4WARD program." "Our lead candidate is called mavorixafor, and it's an oral once-daily capsule. And the amazing thing is its mechanism. What it does is binds to a receptor called CXCR4. And it basically shuts it down a little bit. It's kind of blunting the signaling that normally exists in the cell. And for these patients with WHIM syndrome, their disease is literally caused by too much signaling, by profound over signaling of CXCR4. So we can give them a once-daily capsule that blunts that effect and really then restores the more normalized function of the immune system so that they can combat infections and hopefully minimize their cancer risk." @X4Pharma #WHIMSyndrome #ChronicNeutropenia #CXCR4 #Waldenstrom #RareDisease X4pharma.com Listen to the podcast here

Paula Ragan is the CEO and President of X4 Pharmaceuticals, which focuses on the rare disease WHIM Syndrome. Patients have a deficiency in their immune system, and as a result, this diminishes their ability to fight chronic infections, and they have a higher risk for severe cancers. Paula explains, "If one thinks about doing the right test, it's easy to diagnose, and the right test is doing genetic sequencing. There are commercially available panels, so it exists for the patient and physician communities. The current challenge is getting the physicians to recognize the test is needed. And then to also enable payment. X4 has done a great job in providing free testing through our PATH4WARD program." "Our lead candidate is called mavorixafor, and it's an oral once-daily capsule. And the amazing thing is its mechanism. What it does is binds to a receptor called CXCR4. And it basically shuts it down a little bit. It's kind of blunting the signaling that normally exists in the cell. And for these patients with WHIM syndrome, their disease is literally caused by too much signaling, by profound over signaling of CXCR4. So we can give them a once-daily capsule that blunts that effect and really then restores the more normalized function of the immune system so that they can combat infections and hopefully minimize their cancer risk." @X4Pharma #WHIMSyndrome #ChronicNeutropenia #CXCR4 #Waldenstrom #RareDisease X4pharma.com Download the transcript here

Please join author George Dangas and Associate Editor Brendan Everett as they discuss the article “Colchicine in Cardiovascular Disease.” Dr. Carolyn Lam: Welcome to Circulation on the Run, your weekly podcast summary and backstage pass to the journal and its editors. We're your co-hosts. I'm Dr. Carolyn Lam, Associate Editor from the National Heart Center and Duke National University of Singapore. Dr. Greg Hundley: Welcome, everyone, to 2022. I'm Dr. Greg Hundley, Associate Editor, Director of the Pauley Heart Center at VCU Health in Richmond, Virginia. Carolyn, oh, we're starting off the year with a twist on the feature article. It's a review article on colchicine and cardiovascular disease. But before we get to that, how about we grab a cup of coffee and jump into some of the other articles in the issue? Dr. Carolyn Lam: Absolutely. The new year is starting off with a bonanza issue. This first topic is so important. We know that various non-invasive, intermittent rhythm monitoring strategies have been used to assess arrhythmia recurrences in atrial fibrillation ablation trials. But the question is, what is the frequency and duration of non-invasive rhythm monitoring that accurately detects arrhythmia recurrences and approximates the atrial fibrillation burden derived from continuous monitoring using the gold standard, implantable cardiac monitor? Now to answer this question, investigators Jason Andrade and colleagues from the Montreal Heart Institute, who looked at the rhythm history in 346 patients enrolled in the CIRCA-DOSE trial. They reconstructed the rhythm history using computer simulations and evaluated event-free survivals, sensitivity, negative predictive value, and AF burden in a range of non-invasive monitoring strategies including those used in contemporary AF ablation trials. Dr. Greg Hundley: Ah, very interesting, Carolyn. So what did they find? Dr. Carolyn Lam: Detection of arrhythmia recurrence following ablation was highly sensitive to the monitoring strategy employed between trial discrepancies and outcomes, in fact, may reflect these different monitoring protocols. Binary efficacy outcomes, such as time to AF recurrence, appeared to underestimate the true impact of catheter ablation on the burden of atrial arrhythmia. The most commonly performed intermittent rhythm monitoring techniques, like short duration 24- or 48-hour ambulatory Holter, they do miss a substantial proportion of arrhythmia recurrences and significantly overestimate the true AF burden in patients with recurrences. So based on measures of agreement, serial long-term, that is four seven-day or two 14-day intermittent monitors accumulating at least 28 days of annual monitoring provide estimates of AF burden that are comparable with the implantable cardiac monitor. However, implantable cardiac monitors outperform intermittent monitoring for arrhythmias and should be considered the gold standard for clinical trials. Dr. Greg Hundley: Very nice, Carolyn. It sounds like a lot of clarification on monitoring of AF burden. Well, my first paper comes to us from Dr. Prabhakara Nagareddy from The Ohio State University, The Wexner Medical Center. Carolyn, acute myocardial infarction results in an overzealous production and infiltration of neutrophils in the ischemic heart, and this is mediated in part by granulopoiesis induced by the S100A8/A9 NLRP3, IL-1 beta signaling axis in injury-exposed neutrophils. In this study, Carolyn, the investigators evaluated a hypothesis as to whether IL-1 beta is released locally within the bone marrow by inflammasome prime and reverse migrating neutrophils. Dr. Carolyn Lam: Ah, okay. So what did they find, Greg? Dr. Greg Hundley: Okay, Carolyn. In response to myocardial infarction, the NLRP3 inflammasome prime neutrophils upregulated CXCR4 and reverse migrated to the bone marrow, where they adhered to adhesion molecules like P-selectin on the bone marrow endothelial cells. Second, Carolyn, in the bone marrow, the inflammasome prime neutrophils released IL-1 beta through gasdermin-dependent conduit pores without undergoing the mandatory pyroptosis. Third, genetic and/or pharmacological strategies aimed at limiting reverse migration of inflammasome prime neutrophils to the bone marrow or release of IL-1 beta, both suppressed granulopoiesis and improved cardiac function in mouse models of myocardial infarction. So Carolyn, therefore, strategies aimed at targeting specific signaling pathways within the neutrophils or reducing retention of the inflammasome prime neutrophils in the bone marrow may provide novel avenues to regulate inflammation and improve cardiac outcomes. Dr. Carolyn Lam: Wow, neat, Greg. Thanks for explaining that so nicely. Well, the next paper deals with my favorite topic, heart failure with preserved ejection fraction of HFpEF, and this time looks at mechanisms of sinoatrial node dysfunction. The investigators, led by Dr. Cingolani from Smidt Heart Institute at Cedars-Sinai Medical Center, sought to investigate the role of the intrinsic pacemaker on chronotropic incompetence in HFpEF. They performed extensive sinoatrial node phenotyping, both at baseline and after stress in the well-characterized Dahl salt-sensitive rat model of HFpEF. These rats exhibited limited chronotropic response associated with intrinsic sinoatrial node dysfunction, including impaired beta-adrenergic responsiveness and an alternating leading pacemaker within the sinoatrial node. Prolonged sinoatrial node recovery time and reduced sinoatrial node sensitivity to isoproterenol were confirmed in the two hit mouse model. Adenosine challenge unmasked conduction blocks within the sinoatrial node, which were associated with structural remodeling. Finally, single-cell studies and transcriptomic profiling revealed HFpEF-related alterations in both the membrane clock or iron channels and the calcium clock of the spontaneous calcium release events. Dr. Greg Hundley: Wow, Carolyn, lot of really interesting data here. So what were the clinical implications? Dr. Carolyn Lam: Yeah, it's a really great study. Two models of HFpEF-consistent result in an important topic. Basically, here at the take-home messages. Provocative testing can be valuable to elicit functional abnormalities to facilitate HFpEF diagnosis and considering the exceptionally high clinical and epidemiologic convergence between AFib and HFpEF, sinoatrial node dysfunction may underlie the development of abnormal atrial rhythms in HFpEF. Dr. Greg Hundley: Very nice, Carolyn. More information on HFpEF, again, one of your favorite subjects. Next, we're going to turn to a paper from Dr. Jian Li from the Peking Union Medical College Hospital. Carolyn, doxycycline has previously been demonstrated in a retrospective study to be associated with greater survival in patients with light chain AL amyloidosis. Therefore, Carolyn, this group prospectively compared the efficacy of bortezomib, cyclophosphamide, dexamethasone, or cyclophosphamide B or D, and cyclophosphamide B or D combined with doxycycline for cardiac amyloidosis. Dr. Carolyn Lam: Cool. So what did they find, Greg? Dr. Greg Hundley: Carolyn, this was a multi-center, open-label, randomized controlled trial, and 140 patients underwent randomization. The primary outcome was two-year progression-free survival. Progression-free survival was defined as the time from randomization to death, hematologic progression or organ progression, and that's the heart, the kidney, or the liver. And so Carolyn, these investigators in this trial demonstrated that doxycycline combined with cyclophosphamide B or D failed to prolong progression-free survival or cardiac progression-free survival compared with cyclophosphamide B or D alone in patients with cardiac AL amyloidosis. So Carolyn, a negative study that's quite informative and a very nice editorial that accompanies this article pertaining to future directions for management of AL cardiac amyloid. Dr. Carolyn Lam: Indeed important. Thank you. And there are other important papers in today's issue. There's a Research Letter by Dr. Pfeffer on the impact of sacubitril/valsartan versus ramipril on total heart failure events in the PARADISE-MI trial. Dr. Greg Hundley: Great, Carolyn. In the nail bag, boy, I've got a big list today. First, Dr. Churchwell has an AHA update on the need for policy change to improve maternal cardiovascular health. Next, Dr. Piazza has a Perspective piece on expanding the role of coronary CT angiography in interventional cardiology. There's an ECG challenge from Dr. Yarmohammadi entitled “Dancing Bundles with Stable Sinus Rhythm.” And next, we have our own Darren McGuire who, in this issue for all of 2021, is really recognizing our outstanding reviewers. And we want to thank all the listeners and everyone that reviews for us in this journal. Such an important feature and aspect to the publication of the wonderful articles that we receive. And then finally, there are some highlights from the circulation family of journals. Well, Carolyn, how about we get on to that feature discussion and learn more about colchicine and its use in cardiovascular disease. Dr. Carolyn Lam: Let's go and a Happy New Year, again, everyone. Dr. Greg Hundley: Welcome listeners to this January 4th feature discussion. This week, we're deviating a little bit because we are going to have an author discuss one of our in-depth reviews. As you know, we select those occasionally where they're is a topic that's very relevant in cardiovascular medicine and an investigator or team of investigators or authors will put together a very nice review of a topic. This week, we're going to talk about colchicine, and we have with us Dr. George Dangas from the Icahn School of Medicine at Mount Sinai and our associate editor, Dr. Brendan Everett, who manages this paper and he is from Brigham and Women's Hospital. Welcome, gentlemen. George, we'll start with you. George, why colchicine? Can you tell us a little bit about mechanism of action? Tolerability? Why would we want to use this particular agent in patients with cardiovascular disease? Dr. George Dangas: Thank you very much for the opportunity to join this interesting podcast. Colchicine is indeed an interesting drug. It's been around for centuries, in all honesty. In general, I would say it's a mild anti-inflammatory and in general, it's rather well tolerated. We'll go into those perhaps a little bit later. The precise mechanism is actually interestingly not quite defined. It may have a few ways to act by blocking perhaps the chemotaxis of the leukocytes or the adhesion of the leukocytes or the ability to release their granules, et cetera, but there isn't a specific major one that is targeting. Perhaps, it's targeting more than one mechanism in a mild way, and I think that goes into each utility, as well as the absence of the major side effect that might limit it. Dr. Greg Hundley: Very nice. So you started to mention the word utility, so maybe let's go through some clinical indications, or clinical uses perhaps rather than indications, can you tell us a little bit about its use in individuals with pericarditis? Dr. George Dangas: I think this is where it started to enter the cardiovascular field because we all recognize that pericarditis is an inflammatory disease and inflammation of the pericardium of different reasons perhaps. And anti-inflammatory drug is rather fitted to treat an inflammatory disease and besides, it's not like we had any other drug, in all honesty. Clearly, recurrent pericarditis might be treated with steroids for example, but steroids is not something any cardiologist would jump as a first line and give high doses and all that. Colchicine made its way to pericarditis like acute or recurrent pericarditis, post-cardiac cardiology syndrome, restless syndrome or the specific post-cardiac surgery, major inflammation. And indeed has a daily dosage perhaps with some loading dose or double the daily dosage or something initially and then we give it for a prolonged period of time in order to suppress. I would say this is a reasonable choice rather than jumping to the steroid. And of course, you reserve the steroid for the, I would say, more severe or more recurrent cases. I think everybody understands this type of activity. There've been quite a few clinical studies in this aspect. Again, in the absence of a competitor, I think it's a winner in this area. Dr. Greg Hundley: Very nice. And then, how about atrial fibrillation? Are there uses of this colchicine in patients with atrial fibrillation? Dr. George Dangas: Well, again, it's very interesting that a lot of atrial fibrillation, it may be in some ways inflammatory in origin. And quite frankly, we had an interesting [inaudible 00:14:50] clinical trial in American Heart Association in 2021. I'd like to point out here, the study that postoperative atrial fibrillation was mitigated when, during cardiac surgery, there was a slicing of the posterior pericardial. This allowing the inflammation in some ways that's related there. To me, that was a very interesting observation, though I related to colchicine because it validates the fact that there is something inflammatory in pericardial that related with the postoperative atrial fibrillation. So along these lines, let's go back to colchicine, Afib, and postop Afib, and post-ablation I would say patients. Again, there are risks of some inflammation and that's where the theory of a mild, rather well-tolerated, anti-inflammatory might come in. And there's been few studies, not a large definitive study, but several studies that are the, I would say, component with interesting results with colchicine in these patients. Dr. Greg Hundley: Very good. Another area of cardiovascular disease that's emerging literally with some demonstrable results using colchicine is the realm of ischemic heart disease. Can you walk us through some of the utility myocardial infarction or maybe even post-percutaneous coronary artery intervention? Dr. George Dangas: Again, the hallmark in this type of diseases, cardiovascular disease or coronary heart disease, is the hallmark of role of inflammation in this disease. And we know very well from the studies of the C-reactive protein, importance is a marker of inflammation. Very, very important in the CAD as well as in even the treatment with the antibody canakinumab a little bit earlier in the CANTOS trial a few years earlier at the very high level inhibited inflammation had a benefit and colchicine comes in maybe a milder anti-inflammatory about this agent, but at the same time with significantly less cause and significantly better recognition among the clinicians and a lot less, I would say, tolerability problems or issues are less unknowns. And I think that's where it comes in. The difficulty has been that whenever you go to cardiovascular, the cardiovascular, I would say coronary artery disease specifically, ACS and all that, the level evidence required for the doctors to believe in a therapy is very different than the areas we discussed before where there's little bit of a pericardial disease, for example, not that many drugs, all of a sudden, coronary artery disease, the bar is so high, and that's where the difficulty has been. There've been several studies. They've been interesting results with some benefits, particularly due to the decrease in inflammation and the secondary prevention, one can say. That is really the hallmark of where it aims to benefit in the secondary prevention, but there hasn't been one massive study with clearly superb results. I would say adequately powered single study that is missing in some ways. But several studies have been, again, very, very encouraging, but we learned that there's no much point if loading a lot of doses of high doses of colchicine, and it's a little bit better, again, when you aim with a daily dose towards reduced recurrences, particularly if you started early after an acute event. Dr. Greg Hundley: Very nice. Well, listeners, we're going to now turn to our associate editor, Dr. Brendan Everett, from Brigham and Women's Hospital. Brendan, you have a lot of papers come across your desk. First and foremost, what attracted you to this particular article? Dr. Brendan Everett: Well, thanks, Greg. And kudos to George and his team for putting together a really nice paper. It's great to have this kind of paper come into my inbox. That's specifically because colchicine, I think, has exploded as a really important novel therapy even though the therapy itself is perhaps hundreds of years old, as you heard George say a moment ago, but its role in treating cardiovascular diseases has really begun to emerge rapidly. I think there's a tremendous amount of enthusiasm for other ways to treat our patients who have really a recalcitrant cardiovascular disease, whether that's pericarditis, atrial fibrillation or I think, importantly, ischemic heart disease, because that's such a common disease and something where we're always looking for new ways to help patients live longer with fewer recurrent events. And so this paper I thought did a really good job of capturing the existing evidence for these conditions and some others and giving us a sense of where the strengths of that evidence lay and where the weaknesses were. I thought particular strength was in the tables where the authors laid out each of the trials and the results of the trial, their endpoints, where the benefit was potentially. And also importantly, where risks were seen because I think that's one of the really important questions that remains open with respect to colchicine therapy when we begin to talk about using it in a vast population of people with stable ischemic heart disease or post-myocardial infarction ischemic heart disease. Dr. Greg Hundley: Brendan, tell us a little bit about those risks. Dr. Brendan Everett: I'd be happy to do that. I want to emphasize before I dive in that I think the benefits that George has laid out are important, and I don't want to overshadow what the major trials have seen. But I think the thing that it is at least a little bit of the fly in the ointment, if you will, for colchicine in ischemic heart disease is that a couple of the large trials have shown an increased risk of non cardiovascular mortality or bad non-cardiovascular outcomes. And that's of concern, I think, as we saw in the CANTOS trial, which was the monoclonal antibody trial for canakinumab that George mentioned earlier, there was an increase in infection-related mortality. And so whenever you use an anti-inflammatory drug, you're worried about whether or not you're blunting other compensatory mechanisms that the body has to protect against infection and other diseases. I think it's likely that these findings are the play of chance, but we don't know for sure. For example, in the COLCOT trial, which I think is probably the largest and most interesting trial, which was designed and run in Canada, there was a slightly higher level of pneumonia in patients who got active therapy as compared to placebo. And then, two of the trials that were published more recently including LoDoCo2, which was a trial of about 5,000 patients run in the Netherlands and Australia. There was actually a marginally increased risk of non-cardiovascular mortality. That didn't reach statistical significance, but it was awfully close, and I think it gave people some concern. And then, there was also the COPS trial. Again, all these are really outlined in wonderful detail in the manuscript where there was a slight increase of total death and non-cardiovascular death. These events are few, but they're in a direction in two trials, and so they make people a little bit worried. I think the other thing that I noticed was the high prevalence of myalgia as a side effect. I think, Greg, you're always interested in the clinical implications and yesterday I was in clinic and saw a young patient who had had pericarditis. He had been prescribed colchicine by his primary care physician, and he literally couldn't stand and walk up straight because of the amount of abdominal pain he had, which was unusual. To be honest, I've given colchicine to a hundred patients at least, and none of them have had that profound of a side effect, but it's at least worth considering that some patients will not tolerate the therapy because of adverse effects. Dr. Greg Hundley: Very good. Well, in just 30 seconds or so, for each of you, first George and then Brendan. George, balancing some of the efficacy and then some of the concerns, what do you see is the next studies to be performed really in this sphere of research? Dr. George Dangas: This is a great question. And indeed, the concerns one can say or the issues, I would say, regarding this drug, are indeed real because any drug that suppresses inflammation has this risk. There are two ways one can address those. One is with term administration. You don't prescribe it as an annuity forever, but you prescribe it in a three- to six-month or one-month or try to control the time. I think this is done in clinical practice, in all honesty. I don't think that people are prescribing colchicine for life. Same way when we prescribe statins, for example. On the other hand or from investigational point of view, I think the two sets of information we need and, in all honesty, when you investigate issues regarding mortality or these are rare events, there's only one. You need a very large trial or a very large register. A very large trial preferably and colchicine being an often genetic drug, funding sources are rather limited, but we have NIH chipping in with some funding periodically and that might really be needed. So I want to outline that in the last table of our very large, I would say large table of our manuscript but were very happily outlined many ongoing trials. There are, in atrial fibrillation, three coronary artery disease. One in PCI and two in stroke. Something we didn't touch up again. But again, there's the question of inflammation in stroke. I think there's a lot of work ongoing. Perhaps you can see some meta-analysis, again, in order to get a handle of those risks, but at a rather low rate. It's just a difficult thing to come around. Dr. Greg Hundley: Very good. Brendan, anything to add? Dr. Brendan Everett: I would just add I agree a hundred percent with George just said. I think the only missing piece there is heart failure, which I think is and many have shown that there's an inflammatory component to heart failure, whether it's heart failure with reduced ejection fraction or preserved ejection fraction. And the timing of when that intervention might be, whether it might be before the development of symptoms or because there's a lot of trials out there that have struggled with this question and have unfortunately failed to show any benefit, I would just encourage the listeners of the podcast to look at this paper because it's a really marvelous compilation of the evidence for what is a really hot topic in cardiovascular medicine, a really important topic for a lot of the reasons that George mentioned. It's just very well done and comprehensive. Again, kudos to the authors for making such a great effort at putting something together that has a lot of clinical relevance, I think, and also points the way forward for research as you ask, Greg. Dr. Greg Hundley: Very nice. Well, listeners, we want to thank Dr. George Dangas from Icahn School of Medicine in Mount Sinai and our own associate editor, Dr. Brendan Everett from Brigham and Women's Hospital for bringing us this data pertaining to colchicine benefits, as we know in acute and recurrent pericarditis, but also emerging indications related to post-procedural atrial fibrillation or coronary artery disease. And really, colchicine's targeting of cardiovascular inflammation is being helpful in those alleviating those processes. Well, on behalf of Carolyn and myself, we want to wish you a great week, and we will catch you next week on the run. Dr. Greg Hundley: This program, this copyright of the American Heart Association 2022. The opinions expressed by speakers in this podcast are their own and not necessarily those of the editors or of the American Heart Association. For more, please visit ahajournals.org.

文 | 方舟子这几天据说中国发生了“学术界大地震”，首都医科大学校长饶毅实名举报一名院士两名教授造假。实际情况是这样的：饶毅最近到首都医科大学当校长。国家自然科学基金委员会给该校发函，说有人举报饶毅发表的论文涉嫌造假。饶毅就写了一封答复，初稿发给一些人征求意见，内容主要是反驳造假指控，说方舟子已经查过那些论文了，不是他造假，是别的实验室的共同作者造假，举报他是对他的打击报复。最后是反戈一击，举报了三个人造假，要求国家自然科学基金委员会去查。饶毅本来只是要跟调查他的国家自然科学基金委员会私下吵一架，被他某个幸灾乐祸的“山上的朋友”把回信征求意见稿捅出去，发到了网上。媒体不管该信的前面部分，只截取他后面举报的部分，断章取义要把他打扮成挺身而出的“打假斗士”，他想必很恼火，拒绝接受任何媒体的采访。关于饶毅被举报造假的论文，如饶毅在信中所说，我以前已写过三篇文章做了分析（《关于饶毅、管坤良实验室联合发表的论文数据造假的分析》《再说饶毅、管坤良实验室联合发表的论文数据造假》《三说饶毅、管坤良实验室联合发表的论文数据造假》），在此不再赘述。媒体对此也不关心，他们关心的是饶毅反过来举报别人造假。饶毅在信中是这么说的：“本着帮助贵委的监督委员会改邪归正的精神，建议它做自己应该做的事情，而不是成为中国学术不端者搅混水企图的帮凶。具体建议国家自然科学基金委监督委员会近期:1)有效、有胆魄地彻底调查武汉大学医学院李红良 17 年如一日明目张胆的造假;2)严肃调查中国科学院上海生命科学研究院生化细胞所研究员裴钢 于 1999 年，用贵委三项经费(39630130, 39625015 和 39825110)支持其发 表的论文(Ling et al., PNAS 96:7922-7927)。该篇论文的图3、图 4、图 5 是不可能真实的，只有造假才能产生(众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜，而且居然两个 GPCRs 都是这样的，出 了 3 个同样错误的图)。贵委 20 年不触及这一问题，现在这是实名举报， 贵委不要推卸躲避，洗刷中国科学院因这篇造假文章选出院士的耻辱;3)今年中国科学院上海药物研究所的耿美玉研究员作为通讯作者的文章(Wang et al Cell Research 29:787-803)，号称其发明的药物 GV971 能够通过肠道菌群治疗小鼠的阿尔兹海默症。这篇文章，不造假是不可能的。 现实名举报，请贵委做些好事，为中国科学界洗刷耻辱。”关于武汉大学医学院教授李红良，饶毅他们此前已在网刊《知识分子》上发表过长篇文章分析过其论文数据造假。饶毅他们一直反对在网上揭露学术造假，认为揭露造假应该去学术期刊，为何李红良有此特殊待遇，不得而知。虽然武汉大学校方把李红良保了下来，但李红良的确是造假惯犯，我主持的新语丝网站早在2010年、2014年、2017年已三次揭露过他造假，证据确凿，饶毅说“李红良 17 年如一日明目张胆的造假”，是有依据的。关于耿美玉研发的治疗阿尔茨海默病的药物，虽然我不能像饶毅那样断定“不造假是不可能的”，但那项研究的确是不可信的，我此前已经写w文章分析过（《为何“我国原创治疗阿尔茨海默病新药”不可信》）。所以这里重点说说裴钢的论文。那篇论文研究的是G蛋白偶联受体（GPCR）。这是一类位于细胞膜上的蛋白质，帮助把信号从细胞外传递到细胞内，所以它一端在细胞外，另一端在细胞内，中间部分来来回回跨了七次细胞膜。饶毅信中认为裴钢那篇论文造假的理由就是：“众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜”，所以一定是假的。这个理由是不足为凭的。虽然GPCR的野生型跨七次膜，但是，很多蛋白质有多余部分，去除那些部分并不影响功能。裴钢论文证明的就是去除GPCR的某些部分、只跨五次膜不影响功能。如果像饶毅说的那样，GPCR公认必须有七次跨膜才有功能，那么，裴钢这篇论文就不可能通过评审发表。它得以发表，说明饶毅所说的并非公认的定论。别的实验室后来也发现了有的GPCR只要跨五次膜甚至跨四次、二次、一次膜也有功能（文献1，2，3），并不是非要完整地跨七次膜不可，可见饶毅用以指控造假的依据并不成立。裴钢这篇论文发表后被引用了80多次，相当一部分是自引，影响不大。但是至少有两篇论文研究了它研究的同一种蛋白质（CXCR4）的五跨膜突变，虽然用的实验材料或方法不同，但他们认为结果与裴钢论文相符（文献4, 5）。关于GPCR结构的综述文章，有的引用了裴钢这篇论文（文献6），说明其结果也是被领域同行认可的，至少我没见到有论文、综述对裴钢论文的结论表示异议。当然，结论正确的论文不等于就没有造假，通过伪造、修改实验数据也能碰巧得出正确的结论。饶毅可能还有其他理由认为裴钢论文造假，他没具体指出来，我们不好讨论。指控别人造假，就应该把证据、理由都摆出来，才能引起重视，才有望导致调查。如果饶毅有充分的理由认定裴钢论文造假，认定“该篇论文的图 3、图 4、图 5 是不可能真实的，只有造假才能产生”，那么解决的办法就是重复这三个图的实验，看是不是能得出那样的结果。其实该实验很简单，不难重复。至于饶毅建议由我来监督重复实验，我感谢他对我的信任和认可我的“权威性”，在信中甚至认为我比国家自然科学基金委员会还权威（“如果贵委有谁看不清楚方舟子仔细的分析，如果一个专门机构工作不如业余打假的个人，应该检查自己，也好好学习、天天向上。”），但我既没有自己的实验室也不可能跑去裴钢实验室盯着他们做实验。更合适的办法是裴钢把相关材料（论文中所用的cDNA）送到第三方验证。不过，如果饶毅没有别的证据，仅靠信中说的那条理由，大概没有实验室愿接这个活儿。所以还是希望饶毅能把他认为裴钢论文造假的理由充分地展示出来，如果有的话。毕竟，指控别人学术造假，并非儿戏。2019.12.2文献：1.Duran-Prado M, et al. J Clin Endocrinol Metab (2009) 94:2634–26432.Cordoba-Chacon J, et al. Cell. Mol. Life Sci. (2010) 67:1147–11633.Perron A, et al. J Biol Chem (2005) 280 (11): 10219-274.Roland J, et al. Blood (2003) 101 (2): 399-4065.Hamatake M, et al. Cancer Sci. (2009) 100 (1): 95-1026.Wise H, J Mol Signal (2012) 7: 13

文 | 方舟子这几天据说中国发生了“学术界大地震”，首都医科大学校长饶毅实名举报一名院士两名教授造假。实际情况是这样的：饶毅最近到首都医科大学当校长。国家自然科学基金委员会给该校发函，说有人举报饶毅发表的论文涉嫌造假。饶毅就写了一封答复，初稿发给一些人征求意见，内容主要是反驳造假指控，说方舟子已经查过那些论文了，不是他造假，是别的实验室的共同作者造假，举报他是对他的打击报复。最后是反戈一击，举报了三个人造假，要求国家自然科学基金委员会去查。饶毅本来只是要跟调查他的国家自然科学基金委员会私下吵一架，被他某个幸灾乐祸的“山上的朋友”把回信征求意见稿捅出去，发到了网上。媒体不管该信的前面部分，只截取他后面举报的部分，断章取义要把他打扮成挺身而出的“打假斗士”，他想必很恼火，拒绝接受任何媒体的采访。关于饶毅被举报造假的论文，如饶毅在信中所说，我以前已写过三篇文章做了分析（《关于饶毅、管坤良实验室联合发表的论文数据造假的分析》《再说饶毅、管坤良实验室联合发表的论文数据造假》《三说饶毅、管坤良实验室联合发表的论文数据造假》），在此不再赘述。媒体对此也不关心，他们关心的是饶毅反过来举报别人造假。饶毅在信中是这么说的：“本着帮助贵委的监督委员会改邪归正的精神，建议它做自己应该做的事情，而不是成为中国学术不端者搅混水企图的帮凶。具体建议国家自然科学基金委监督委员会近期:1)有效、有胆魄地彻底调查武汉大学医学院李红良 17 年如一日明目张胆的造假;2)严肃调查中国科学院上海生命科学研究院生化细胞所研究员裴钢 于 1999 年，用贵委三项经费(39630130, 39625015 和 39825110)支持其发 表的论文(Ling et al., PNAS 96:7922-7927)。该篇论文的图3、图 4、图 5 是不可能真实的，只有造假才能产生(众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜，而且居然两个 GPCRs 都是这样的，出 了 3 个同样错误的图)。贵委 20 年不触及这一问题，现在这是实名举报， 贵委不要推卸躲避，洗刷中国科学院因这篇造假文章选出院士的耻辱;3)今年中国科学院上海药物研究所的耿美玉研究员作为通讯作者的文章(Wang et al Cell Research 29:787-803)，号称其发明的药物 GV971 能够通过肠道菌群治疗小鼠的阿尔兹海默症。这篇文章，不造假是不可能的。 现实名举报，请贵委做些好事，为中国科学界洗刷耻辱。”关于武汉大学医学院教授李红良，饶毅他们此前已在网刊《知识分子》上发表过长篇文章分析过其论文数据造假。饶毅他们一直反对在网上揭露学术造假，认为揭露造假应该去学术期刊，为何李红良有此特殊待遇，不得而知。虽然武汉大学校方把李红良保了下来，但李红良的确是造假惯犯，我主持的新语丝网站早在2010年、2014年、2017年已三次揭露过他造假，证据确凿，饶毅说“李红良 17 年如一日明目张胆的造假”，是有依据的。关于耿美玉研发的治疗阿尔茨海默病的药物，虽然我不能像饶毅那样断定“不造假是不可能的”，但那项研究的确是不可信的，我此前已经写w文章分析过（《为何“我国原创治疗阿尔茨海默病新药”不可信》）。所以这里重点说说裴钢的论文。那篇论文研究的是G蛋白偶联受体（GPCR）。这是一类位于细胞膜上的蛋白质，帮助把信号从细胞外传递到细胞内，所以它一端在细胞外，另一端在细胞内，中间部分来来回回跨了七次细胞膜。饶毅信中认为裴钢那篇论文造假的理由就是：“众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜”，所以一定是假的。这个理由是不足为凭的。虽然GPCR的野生型跨七次膜，但是，很多蛋白质有多余部分，去除那些部分并不影响功能。裴钢论文证明的就是去除GPCR的某些部分、只跨五次膜不影响功能。如果像饶毅说的那样，GPCR公认必须有七次跨膜才有功能，那么，裴钢这篇论文就不可能通过评审发表。它得以发表，说明饶毅所说的并非公认的定论。别的实验室后来也发现了有的GPCR只要跨五次膜甚至跨四次、二次、一次膜也有功能（文献1，2，3），并不是非要完整地跨七次膜不可，可见饶毅用以指控造假的依据并不成立。裴钢这篇论文发表后被引用了80多次，相当一部分是自引，影响不大。但是至少有两篇论文研究了它研究的同一种蛋白质（CXCR4）的五跨膜突变，虽然用的实验材料或方法不同，但他们认为结果与裴钢论文相符（文献4, 5）。关于GPCR结构的综述文章，有的引用了裴钢这篇论文（文献6），说明其结果也是被领域同行认可的，至少我没见到有论文、综述对裴钢论文的结论表示异议。当然，结论正确的论文不等于就没有造假，通过伪造、修改实验数据也能碰巧得出正确的结论。饶毅可能还有其他理由认为裴钢论文造假，他没具体指出来，我们不好讨论。指控别人造假，就应该把证据、理由都摆出来，才能引起重视，才有望导致调查。如果饶毅有充分的理由认定裴钢论文造假，认定“该篇论文的图 3、图 4、图 5 是不可能真实的，只有造假才能产生”，那么解决的办法就是重复这三个图的实验，看是不是能得出那样的结果。其实该实验很简单，不难重复。至于饶毅建议由我来监督重复实验，我感谢他对我的信任和认可我的“权威性”，在信中甚至认为我比国家自然科学基金委员会还权威（“如果贵委有谁看不清楚方舟子仔细的分析，如果一个专门机构工作不如业余打假的个人，应该检查自己，也好好学习、天天向上。”），但我既没有自己的实验室也不可能跑去裴钢实验室盯着他们做实验。更合适的办法是裴钢把相关材料（论文中所用的cDNA）送到第三方验证。不过，如果饶毅没有别的证据，仅靠信中说的那条理由，大概没有实验室愿接这个活儿。所以还是希望饶毅能把他认为裴钢论文造假的理由充分地展示出来，如果有的话。毕竟，指控别人学术造假，并非儿戏。2019.12.2文献：1.Duran-Prado M, et al. J Clin Endocrinol Metab (2009) 94:2634–26432.Cordoba-Chacon J, et al. Cell. Mol. Life Sci. (2010) 67:1147–11633.Perron A, et al. J Biol Chem (2005) 280 (11): 10219-274.Roland J, et al. Blood (2003) 101 (2): 399-4065.Hamatake M, et al. Cancer Sci. (2009) 100 (1): 95-1026.Wise H, J Mol Signal (2012) 7: 13

文 | 方舟子这几天据说中国发生了“学术界大地震”，首都医科大学校长饶毅实名举报一名院士两名教授造假。实际情况是这样的：饶毅最近到首都医科大学当校长。国家自然科学基金委员会给该校发函，说有人举报饶毅发表的论文涉嫌造假。饶毅就写了一封答复，初稿发给一些人征求意见，内容主要是反驳造假指控，说方舟子已经查过那些论文了，不是他造假，是别的实验室的共同作者造假，举报他是对他的打击报复。最后是反戈一击，举报了三个人造假，要求国家自然科学基金委员会去查。饶毅本来只是要跟调查他的国家自然科学基金委员会私下吵一架，被他某个幸灾乐祸的“山上的朋友”把回信征求意见稿捅出去，发到了网上。媒体不管该信的前面部分，只截取他后面举报的部分，断章取义要把他打扮成挺身而出的“打假斗士”，他想必很恼火，拒绝接受任何媒体的采访。关于饶毅被举报造假的论文，如饶毅在信中所说，我以前已写过三篇文章做了分析（《关于饶毅、管坤良实验室联合发表的论文数据造假的分析》《再说饶毅、管坤良实验室联合发表的论文数据造假》《三说饶毅、管坤良实验室联合发表的论文数据造假》），在此不再赘述。媒体对此也不关心，他们关心的是饶毅反过来举报别人造假。饶毅在信中是这么说的：“本着帮助贵委的监督委员会改邪归正的精神，建议它做自己应该做的事情，而不是成为中国学术不端者搅混水企图的帮凶。具体建议国家自然科学基金委监督委员会近期:1)有效、有胆魄地彻底调查武汉大学医学院李红良 17 年如一日明目张胆的造假;2)严肃调查中国科学院上海生命科学研究院生化细胞所研究员裴钢 于 1999 年，用贵委三项经费(39630130, 39625015 和 39825110)支持其发 表的论文(Ling et al., PNAS 96:7922-7927)。该篇论文的图3、图 4、图 5 是不可能真实的，只有造假才能产生(众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜，而且居然两个 GPCRs 都是这样的，出 了 3 个同样错误的图)。贵委 20 年不触及这一问题，现在这是实名举报， 贵委不要推卸躲避，洗刷中国科学院因这篇造假文章选出院士的耻辱;3)今年中国科学院上海药物研究所的耿美玉研究员作为通讯作者的文章(Wang et al Cell Research 29:787-803)，号称其发明的药物 GV971 能够通过肠道菌群治疗小鼠的阿尔兹海默症。这篇文章，不造假是不可能的。 现实名举报，请贵委做些好事，为中国科学界洗刷耻辱。”关于武汉大学医学院教授李红良，饶毅他们此前已在网刊《知识分子》上发表过长篇文章分析过其论文数据造假。饶毅他们一直反对在网上揭露学术造假，认为揭露造假应该去学术期刊，为何李红良有此特殊待遇，不得而知。虽然武汉大学校方把李红良保了下来，但李红良的确是造假惯犯，我主持的新语丝网站早在2010年、2014年、2017年已三次揭露过他造假，证据确凿，饶毅说“李红良 17 年如一日明目张胆的造假”，是有依据的。关于耿美玉研发的治疗阿尔茨海默病的药物，虽然我不能像饶毅那样断定“不造假是不可能的”，但那项研究的确是不可信的，我此前已经写w文章分析过（《为何“我国原创治疗阿尔茨海默病新药”不可信》）。所以这里重点说说裴钢的论文。那篇论文研究的是G蛋白偶联受体（GPCR）。这是一类位于细胞膜上的蛋白质，帮助把信号从细胞外传递到细胞内，所以它一端在细胞外，另一端在细胞内，中间部分来来回回跨了七次细胞膜。饶毅信中认为裴钢那篇论文造假的理由就是：“众所周知 GPCR 需要七重跨膜区域才有功能，裴钢号称只要 5 重跨膜”，所以一定是假的。这个理由是不足为凭的。虽然GPCR的野生型跨七次膜，但是，很多蛋白质有多余部分，去除那些部分并不影响功能。裴钢论文证明的就是去除GPCR的某些部分、只跨五次膜不影响功能。如果像饶毅说的那样，GPCR公认必须有七次跨膜才有功能，那么，裴钢这篇论文就不可能通过评审发表。它得以发表，说明饶毅所说的并非公认的定论。别的实验室后来也发现了有的GPCR只要跨五次膜甚至跨四次、二次、一次膜也有功能（文献1，2，3），并不是非要完整地跨七次膜不可，可见饶毅用以指控造假的依据并不成立。裴钢这篇论文发表后被引用了80多次，相当一部分是自引，影响不大。但是至少有两篇论文研究了它研究的同一种蛋白质（CXCR4）的五跨膜突变，虽然用的实验材料或方法不同，但他们认为结果与裴钢论文相符（文献4, 5）。关于GPCR结构的综述文章，有的引用了裴钢这篇论文（文献6），说明其结果也是被领域同行认可的，至少我没见到有论文、综述对裴钢论文的结论表示异议。当然，结论正确的论文不等于就没有造假，通过伪造、修改实验数据也能碰巧得出正确的结论。饶毅可能还有其他理由认为裴钢论文造假，他没具体指出来，我们不好讨论。指控别人造假，就应该把证据、理由都摆出来，才能引起重视，才有望导致调查。如果饶毅有充分的理由认定裴钢论文造假，认定“该篇论文的图 3、图 4、图 5 是不可能真实的，只有造假才能产生”，那么解决的办法就是重复这三个图的实验，看是不是能得出那样的结果。其实该实验很简单，不难重复。至于饶毅建议由我来监督重复实验，我感谢他对我的信任和认可我的“权威性”，在信中甚至认为我比国家自然科学基金委员会还权威（“如果贵委有谁看不清楚方舟子仔细的分析，如果一个专门机构工作不如业余打假的个人，应该检查自己，也好好学习、天天向上。”），但我既没有自己的实验室也不可能跑去裴钢实验室盯着他们做实验。更合适的办法是裴钢把相关材料（论文中所用的cDNA）送到第三方验证。不过，如果饶毅没有别的证据，仅靠信中说的那条理由，大概没有实验室愿接这个活儿。所以还是希望饶毅能把他认为裴钢论文造假的理由充分地展示出来，如果有的话。毕竟，指控别人学术造假，并非儿戏。2019.12.2文献：1.Duran-Prado M, et al. J Clin Endocrinol Metab (2009) 94:2634–26432.Cordoba-Chacon J, et al. Cell. Mol. Life Sci. (2010) 67:1147–11633.Perron A, et al. J Biol Chem (2005) 280 (11): 10219-274.Roland J, et al. Blood (2003) 101 (2): 399-4065.Hamatake M, et al. Cancer Sci. (2009) 100 (1): 95-1026.Wise H, J Mol Signal (2012) 7: 13

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.25.266361v1?rss=1 Authors: De Leo, F., Giacomo, Q., De Marchis, F., Malisa, M. V., Bianchi, M. E., Musco, G. Abstract: HMGB1 is a key molecule that both triggers and sustains inflammation following infection or injury, and is involved in a large number of pathologies, including cancer. HMGB1 participates to the recruitment of inflammatory cells forming a heterocomplex with the chemokine CXCL12 (HMGB1/CXCL12), herewith activating the G-protein coupled receptor CXCR4. Thus, identification of molecules that disrupt this heterocomplex can offer novel pharmacological opportunities to treat inflammation related diseases. To identify new HMGB1/CXCL12 inhibitors we have performed a study on the ligandability of the single HMG boxes of HMGB1 followed by a virtual screening campaign on both HMG boxes using Zbc Drugs and three different docking programs (Glide, AutoDock Vina, AutoDock 4.2.6). The best poses in terms of scoring functions, visual inspection and predicted ADME properties were further filtered according to a pharmacophore model based on known HMGB1 binders and clustered according to their structures. Eight compounds representative of the clusters were tested for HMGB1 binding by NMR. We identified 5,5' methylenedi-2,3-cresotic acid (2a) as binder of both HMGB1 and CXCL12; 2a also targets the HMGB1/CXCL12 heterocomplex. In cell migration assays 2a inhibited the chemotactic activity of HMGB1/CXCL12 with IC50 in the subnanomolar range, the best documented up to now. These results pave the way for future structure activity relationship studies to optimize the pharmacological targeting of HMGB1/CXCL12 for anti-inflammatory purposes. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.04.235994v1?rss=1 Authors: Strausz, S., Ruotsalainen, S. E., Ollila, H. M., Karjalainen, J., Reeve, M., Kurki, M., Mars, N., Havulinna, A. S., Kiiskinen, T., Mansour Aly, D., Ahlqvist, E., Teder-Laving, M., Palta, P., Groop, L., Magi, R., Makitie, A., Salomaa, V., Bachour, A., Tuomi, T., Palotie, A., Palotie, T., Ripatti, S. Abstract: There is currently only limited understanding of the genetic aetiology of obstructive sleep apnoea (OSA). The aim of our study is to identify genetic loci associated with OSA risk and to test if OSA and its comorbidities share a common genetic background. We conducted the first large-scale genome-wide association study of OSA using FinnGen Study (217,955 individuals) with 16,761 OSA patients identified using nationwide health registries. We estimated 8.3% [0.06-0.11] heritability and identified five loci associated with OSA (P < 5.0x10^-8): rs4837016 near GTPase activating protein and VPS9 domains 1 (GAPVD1), rs10928560 near C-X-C motif chemokine receptor 4 (CXCR4), rs185932673 near Calcium/calmodulin-dependent protein kinase ID (CAMK1D) and rs9937053 near Fat mass and obesity-associated protein (FTO) - a variant previously associated with body mass index (BMI). In a BMI-adjusted analysis, an association was observed for rs10507084 near Rhabdomyosarcoma 2 associated transcript (RMST)/NEDD1 gamma-tubulin ring complex targeting factor (NEDD1). We found genetic correlations between OSA and BMI (rg=0.72 [0.62-0.83]) and with comorbidities including hypertension, type 2 diabetes (T2D), coronary heart disease (CHD), stroke, depression, hypothyroidism, asthma and inflammatory rheumatic diseases (IRD) (rg > 0.30). Polygenic risk score (PRS) for BMI showed 1.98-fold increased OSA risk between the highest and the lowest quintile and Mendelian randomization supported a causal relationship between BMI and OSA. Our findings support the causal link between obesity and OSA and joint genetic basis between OSA and comorbidities. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.23.212423v1?rss=1 Authors: Badner, A., Reinhardt, E. K., Nguyen, T. V., Midani, N., Marshall, A. T., Lepe, C., Echeverria, K., Lepe, J., Torrecampo, V., Bertan, S. H., Tran, S. H., Anderson, A. J., Cummings, B. J. Abstract: Human neural stem cells (hNSCs) have potential as a cell therapy following traumatic brain injury (TBI). While various studies have demonstrated the efficacy of NSCs from on-going culture, there is a significant gap in our understanding of freshly thawed cells from cryobanked stocks - a more clinically-relevant source. To address these shortfalls, the therapeutic potential of our previously validated Shef-6.0 human embryonic stem cell (hESC)-derived hNSC line was tested following long-term cryostorage and thawing prior to transplant. Immunodeficient athymic nude rats received a moderate unilateral controlled cortical impact (CCI) injury. At 4-weeks post-injury, 6x105 freshly thawed hNSCs were transplanted into six injection sites (2 ipsi- and 4 contra-lateral) with 53.4% of cells surviving three months post-transplant. Interestingly, most hNSCs were engrafted in the meninges and the lining of lateral ventricles, associated with high CXCR4 expression and a chemotactic response to SDF1alpha (CXCL12). While some expressed markers of neuron, astrocyte, and oligodendrocyte lineages, the majority remained progenitors, identified through doublecortin expression (78.1%). Importantly, transplantation resulted in improved spatial learning and memory in Morris water maze navigation and reduced risk-taking behavior in an elevated plus maze. Investigating potential mechanisms of action, we identified an increase in ipsilateral host hippocampus cornu ammonis (CA) neuron survival, contralateral dentate gyrus (DG) volume and DG neural progenitor morphology as well as a reduction in neuroinflammation. Together, these findings validate the potential of hNSCs to restore function after TBI and demonstrate that long-term bio-banking of cells and thawing aliquots prior to use may be suitable for clinical deployment. Copy rights belong to original authors. Visit the link for more info

WHIM syndrome is a rare, inherited, primary immunodeficiency disease caused by mutations to the CXCR4 receptor gene. Because of the role CXCR4 plays in the immune system, it is implicated in a number of rare diseases. X4 Pharmaceuticals, a company founded by rare disease pioneer Henri Termeer and other Genzyme alums, is developing a pipeline of CXCR4-targeted therapies. We spoke to Paula Ragan, co-founder, president and CEO of X4, about WHIM syndrome, the role CXCR4 plays in the immune system, and how the company’s experimental therapy Mavorixafor may be able to treat a range of rare conditions.

This month on Episode 6 of the Discover CircRes podcast, host Cindy St. Hilaire highlights five featured articles from the October 25 and November 8, 2019 issues of Circulation Research and talks with Coleen McNamara and Aditi Upadhye about their article, Diversification and CXCR4-Dependent Establishment of the Bone Marrow B-1a Cell Pool Governs Atheroprotective IgM Production Linked To Human Coronary Atherosclerosis.   Article highlights:   Omura, et al. ADAMTS8 in Pulmonary Hypertension.   Rödel, et al. Blood Flow Suppresses CCM Phenotypes in Zebrafish   Cai, et al. Proteomics Assessment of hPSC-CM Maturation   Shin, et al. Leptin Causes Hypertension Via Carotid Body Trpm7   Lin , et al. Cellular Heterogeneity in Elastin Deposition   Transcript Dr Cindy St. Hilaire:          Hi. Welcome to Discover CircRes, the monthly podcast of the American Heart Association's journal, Circulation Research. I'm your host, Dr Cindy St. Hilaire and I'm an assistant professor of medicine at the University of Pittsburgh. In this episode I'm going to share with you some highlights from recent articles that were published in the October 25th and our November 8th issues of Circulation Research. We're also going to have an in-depth conversation with doctors Coleen McNamara and Aditi Upadhye, who are the lead authors in one of the exciting discoveries from our October 25th issue. The first article I want to share with you is titled ADAMTS8 promotes the development of pulmonary arterial hypertension and right ventricular failure, a possible novel therapeutic target. The first author is Junichi Omura and the corresponding author is Hiroaki Shimokawa, and the work was conducted at Tohoku University, Sendai, Japan. Pulmonary hypertension is caused from the excessive proliferation of the vasculature in the lungs. It has contributions from smooth muscle cells, endothelial cells, inflammatory cells, and these cells proliferate and occlude the small vessels in the lungs. And this occlusion leads ultimately to failure of the right heart ventricle. Current therapies only treat the symptoms, not the underlying pathology. So there really is a big push right now to try to discover novel therapeutic targets. The authors of this study performed a gene expression screen, and in this screen, they compared pulmonary artery smooth muscle cells from pulmonary hypertension patients to those same cells from healthy controls. The research has found numerous differentially-expressed genes. However, they chose to focus on one called ADAMTS8. And they focused on this because the protein is expressed specifically in the lungs and heart tissues, and it was significantly upregulated in the patient's cells. So ADAMTS8 is a secreted zinc dependent protease, and this protease function makes it potentially a druggable target. So similar to human cells, ADAMTS8 was also found to be upregulated in the lungs of mice with pulmonary hypertension and a lack of vascular ADAMTS8 attenuated the disease symptoms. Conversely, overexpression of ADAMTS8 in pulmonary artery smooth muscle cells from both mice and humans prompted increased proliferation. They performed a high throughput screen to try and identify compounds that would suppress ADAMTS8 and pulmonary artery smooth muscle cell proliferation. And in this screen, they found mebendazole, which is a drug that is already in clinical use for parasitic worm infections. Thus, the study not only pins ADAMTS8 as a driver of pulmonary hypertension, but also suggests a potential existing drug might be useful for treating it. The next manuscript I want to share with you is titled Blood Flow Suppresses Vascular Anomalies In a Zebrafish Model of Cerebral Cavernous Malformations. The first author is Claudia Jasmin Rödel, and the corresponding author is Salim Abdelilah-Seyfried, and they are from the University of Potsdam in Potsdam, Germany. Vessel diameter and geometry as well as blood velocity and flow speed, all affect how the flow of blood impacts biomechanical forces that are received by the endothelial cells that line the lumen of vessels. Pathological changes in biomechanical signaling pathways or abnormal patterns of blood flow have been implicated in the etiology of various vascular diseases, and this manuscript is focusing on one: cerebral cavernous malformations, or CCMs. There are various genetic causes of CCMs, and this combined with several lines of evidence, point to a role for blood flow in CCM lesion development. Specifically, patients typically develop CCM lesions only in low perfused venous capillaries. Those are slow flow vessels. Rarely are high flow vessels affected. The authors want to answer the question, why do CCMs develop in low flow areas and more broadly, what is the role of hemodynamic forces in CCM pathology? To explore the role of blood flow and vascular remodeling, they use a zebrafish model. This is a great model to study this specific type of malformation, because the zebrafish itself is transparent and you can do an amazing way of imaging and I highly recommend that you go online and check out some of the videos that are supplemental figures for this paper. They're beautiful, they're neat, and you can really see the blood flow in these zebrafish models that they use. Okay, so which models did they use? They used ones that had normal levels of blood flow or normal speeds of blood flow, and then a zebrafish that is actually absent of any blood flow. Which is crazy that it can live for any amount of time. And so they use these zebrafish and looked at the lateral dorsal aorta, which is a high shear stress vascular bed. They found that blood flow induces a protective response in endothelial cells. This finding helps to explain why CCM patients never suffer from vascular anomalies within highly perfused blood vessels since these vessels are protected by the flow itself. The next paper I want to highlight is titled An Unbiased Proteomics Method to Assess the Maturation of Human Pluripotent Stem Cell-Derived Cardiomyocytes. The first author is Wenxuan Cai and the corresponding author is Ying Ge, and they are from the University of Wisconsin Madison in Madison, Wisconsin. Cardiomyocytes are the beating cells of the heart and they're very difficult to work with in culture as they don't proliferate very well. As such, scientists are moving to use human induced pluripotent STEM cells as means to create cardiomyocytes. So cardiomyocytes derived from human pluripotent stem cells are a valuable resource for drug discovery and screening and disease modeling. While useful, these pluripotent stem cell-derived cardiomyocytes remain immature compared to their natural adult counterparts, and this immaturity slightly reduces their utility. So there are now several methods that people use to promote maturation of cardiomyocytes, but currently there's no consensus on the best way to assess cardiomyocyte maturity, or rather, IPS cardiomyocyte maturity. In this manuscript, Cai and colleagues have established a straightforward yet comprehensive mass spectrometry approach to ensure cardiomyocyte maturity. This method combines analysis of a subset of intact proteins with an unbiased screen of digested peptide fragments. The team used the method to examine early and late stage maturation of cardiomyocytes derived from embryonic, as well as human induced pluripotent stem cell sources, validating their findings against cells from mouse hearts. For the intact protein analysis, sarcomeres were isolated from cell samples which enabled the identification of the major sarcomeric proteins, as well as any post-translational modifications on these proteins that can fine tune our assessment of maturity. The unbiased screen further identified both known and novel maturation markers. This study not only provides a handy tool for assessing IPS-derived cardiomyocyte maturity, but it also defines a set of maturity markers for cross reference in future studies. The next paper I want to discuss is titled Leptin Induces Hypertension Acting on Transient Receptor Potential Melastatin 7, Trpm7, Channel In the Carotid Body. The first author is Mi-Kyung Shin, and the corresponding author is Vsevolod Polotsky, and they are from the Johns Hopkins University in Baltimore, Maryland. Leptin is a hormone that is secreted from fatty tissue, and it's secreted in response to eating something fatty and delicious. Leptin signaling increases metabolism and blood pressure, and it also helps to reduce appetite. That is, if you don't eat the fatty food too fast. So, obese individuals can exhibit high levels of leptin, yet their metabolism and appetite may be unaltered, while hypertension may still develop. Leptin's effects on appetite metabolism are mediated via signaling in the brain, while its effects on blood pressure are thought to be mediated elsewhere. In this manuscript, the authors suspected that the carotid body has something to do with this. The carotid body is a cluster of cells in the neck that detect blood levels of oxygen and other substrates, and the carotid body cells can communicate the information to the brain via the carotid sinus nerve. The carotid body has abundant expression of leptin receptor, and moreover, leptin has been shown to increase carotid sinus nerve firing. So in this manuscript, the authors now show that infusions of leptin into mice increased hypertension in the animals only when the carotid sinus nerve was intact. They also showed that hypertension in these mice was dependent on the iron channel Trpm7, which is very abundant in the carotid body. Inhibition of Trpm7 prevented the leptin-induced hypertension. Together, these results begin to explain why obese individuals' leptin still induces hypertension when the hormone's other effects on appetite and metabolism are diminished. They suggest that inhibition of Trpm7 could perhaps be a way to treat the hypertension seen in obese individuals. The last paper I want to highlight before we move over to our interview is titled Heterogeneous Cellular Contributions to Elastic Laminae Formation and Arterial Wall Development. The first author is Chien-Jung Lin, and the corresponding author is Jessica Wagenseil from the Washington University in St. Louis. Elastin is the extracellular matrix protein that provides structure to both large and small arteries. Vascular smooth muscle cells are known to produce the layered elastic laminae found in elastic arteries. However, they synthesize very little elastin in more muscular arteries. Muscular arteries also have well-defined internal elastic laminae that separates the smooth muscle cells from the endothelial cells, but the source of the elastin in these muscular arteries is not well-defined. The goal of this study was to define the extent to which endothelial cells can contribute to elastin in the eternal elastic laminae of various arteries. To address this question, they created several new strains of mice in which elastin is deleted specifically in a smooth muscle or an endothelial cell. They found that smooth muscle cells and endothelial cells can both independently form an internal elastic lamina in elastic arteries. In muscular and resistance arteries, however, endothelial cells are the major source of elastin. Further, in the ascending aorta, it was noted that ill-formed internal elastic laminae was associated with neointimal formation, confirming that the internal elastic laminae is a critical physical barrier for smooth muscle cells and endothelial cells in large elastic arteries. This study provides new information about how smooth muscle cells and endothelial cells contribute to elastin production in the artery wall, and also how local elastic laminae defects may contribute to cardiovascular disease. I'm here with Dr Coleen McNamara and Aditi Upadhye, and we'll be discussing their paper titled Diversification and CXCR4-Dependent Establishment of the Bone Marrow B-1a Cell Pool Governs Atheroprotective IgM Production Linked to Human Coronary Atherosclerosis. And this paper is was published in our October 25th edition of the journal. So thank you both so much for joining me today. Dr Coleen McNamara:    Thank you for having us. Dr Aditi Upadhye:            Thank you. Dr Cindy St. Hilaire:          I'm really looking forward to learning more about this paper. First, I'm wondering if you could just please introduce yourselves and give us a little bit about your background. Dr Coleen McNamara:    Well, I'm Coleen McNamara. I'm a physician scientist in the Cardiovascular Research Center at the University of Virginia in cardiovascular medicine. And my laboratory studies B cells and atherosclerosis predominantly. And that's the topic of Aditi's paper. Dr Aditi Upadhye:            And I'm Aditi Upadhye. I'm a PhD student in Coleen's lab and my project in Coleen's lab has focused on the role of CXCR4 in B-1 cell IgM production in atherosclerosis. Dr Cindy St. Hilaire:          If this is your project, you must be nearing the end of graduate school then. Dr Aditi Upadhye:            Yes, very close. Dr Cindy St. Hilaire:          Excellent. And congratulations on a beautiful paper. Dr Aditi Upadhye:            Thank you so much. Dr Cindy St. Hilaire:          So I was just reading the paper and I did see that you stated the objective of the paper, was that you wanted to characterize bone marrow IgM repertoire and determine whether CXCR4 regulated the B-1 cell production of this atheroprotective IgM. Could you maybe just give us a quick primer on what all those words mean? What is a B-1 cell, what is IgM, and what is this atheroprotectiveness, and why is this important to research? Dr Aditi Upadhye:            Sure. So research over the past few decades has shown that the role of B cells in atherosclerosis is subset specific. So in mice there are two broad categories of B cells. B-1 and B-2. And B-2 cells are the ones you typically learn about in immunology classes. They're the ones that produce really high affinity class-switched antibodies in a T-cell dependent manner. And there is evidence that B-2 cells are atherogenic. So either through their ability to modulate T-cells through cytokine production, or through their production of IgG and IgE antibodies, they may have atherogenic capability. B-1 cells are very, very different. They produce what are called these natural IgM antibodies. So they're present even in germ-free mice that don't have any prior antigen exposure, exogenous antigen exposure. And the kind of paradigm in the field thus far had been that B-1 cells produce germline-encoded antibodies. So they don't acquire quite as much diversity as their B-2 cell counterparts do. And really importantly, it has been shown that B-1 cells are an atheroprotective cell subset, primarily through their ability to produce IgM. So our coauthor, Dr Joseph Witztum, previously demonstrated that B-1 cells produced IgM antibodies against oxidation specific epitopes that arise on oxidized LDL in atherosclerosis. But really the mechanisms that regulate IgM production and what these IgMs are targeted against is less known. And that's something that we were trying to get at with this paper. Dr Cindy St. Hilaire:          One of the things you talked about in one of the earlier figures in your paper was that there's differences in the chemokine expression between these B cells that are in the spleen versus when they're in the bone marrow. And these differences are apparent at baseline, but also under hyperlipidemic conditions. Is there a cause or a consequence angle to asking this question about B-1 cells and atheroprotectiveness? Dr Aditi Upadhye:            Yeah, I think so. One of the points of this paper is that B-1 cells are very heterogeneous and so they may be going to multiple locations, not just the bone marrow, which we focus on in our paper, but also the spleen, also the perivascular adipose tissue, are sites that we're also interested in looking at. So the fact that there is different chemokine ligand expression level on these different sites might guide them to these different places and might help with their function. Dr Cindy St. Hilaire:          Yeah, and I guess that's a perfect segue for my next question. And it seems that the CXCR4 expression on the cells is really key to their proper migration and then the subsequent secretion of the IgM. Do we know what's happening to CXCR4 expression either as we age or as atherosclerosis progresses? Is there any evidence of environmental or behavioral or genetic angles that might predispose an individual to having more or less CXCR4 on their B cells? Dr Aditi Upadhye:            That's a great question. So there are a lot of things that regulate chemokine receptor expression, including expression of the ligands too. I don't know that much about how CXCR4 expression changes with age or with atherosclerosis. At least in mice, it seems that CXCR4 doesn't change during hyperlipidemia. So for example, in C57 black 6 mice versus a ApoE knockout mice, either child fed or Western diet fed, CXCR4 doesn't seem to change on the one cell subsets. Dr Cindy St. Hilaire:          Interesting. Maybe a future project then. Dr Aditi Upadhye:            Yeah. Yeah. Dr Cindy St. Hilaire:          So I found it really interesting, I think it was in figure five, I always like to try to pick out my favorite figures. My favorite figures of this paper are three, five, and seven. And so... Are those your favorite? But so I guess one of the things that I thought was interesting is that you made a mouse, a multiple knockout mouse that had ApoE knockout and it also was not able to make IgM antibodies. Is that correct? So when you took that mouse and then you looked at it, I think at 80 weeks of age, you could see differences in the atherosclerosis on these mice, but then you couldn't see it on kind of the standard model of what probably most atherosclerosis labs use. And that is a younger mouse that's put on a high fat diet for a shorter window of time. And so could you maybe talk about what that difference means, what your study shows, and then how do we move forward with studying the role of inflammation and atherosclerosis in younger versus older mice? Dr Aditi Upadhye:            Yeah, that's a great question. And I think that every model has its caveats that, and that's something that we ran into when we were trying to show whether B-1 cell CXCR4 is important in atheroprotection. But I think what our findings suggest is that there is a very delicate balance between the amount of IgM that you have and the lipid burden that you have. And in any given model, these might be factors to consider when it comes to studying atherosclerosis. Just taking those factors into consideration when you're analyzing your atherosclerosis results. Dr Cindy St. Hilaire:          Absolutely. Dr Coleen McNamara:    One of the reasons we liked this 100-week-old, or the 80-week-old mouse is the one where if it doesn't have IgM, there's significantly more atherosclerosis even on a chow diet. And so that's a cholesterol of about 300 or 400, and then an 80 to a 100-week old mouse is about the equivalent of a 70-year-old person, which is sort of more akin to the human situation. And so in that setting, the IgMs matter, whereas it didn't look like the IgMs as Aditi said were really capable of blocking the oxidized lipids that were generated in younger mice that had cholesterols well over a thousand. So we felt like that that was really relevant, which is why we use that same model for when we did the single cell sorting and sequenced the antibody repertoire. Thinking that that would give us more insight into the role of age and modest hyperlipidemia, which is more the clinical scenario. Dr Cindy St. Hilaire:          Do you think that has implications for how humans with familial hypercholesterolemia are treated versus someone with just a lower level but still elevated lipid profile? Dr Coleen McNamara:    Yeah, I do, and I think that's really an important point, Cindy, because the vast majority of people that suffer from cardiovascular disease, have heart attacks, die of cardiovascular disease, are typically older people with modest cholesterol levels. Familial hypercholesterolemia, obviously in those patients, they get significant cardiovascular disease at young ages. But that's certainly in a relative sense, a much less common occurrence. So I think that the model and the mechanisms that we were looking at are more applicable than garden variety atherosclerosis. Dr Cindy St. Hilaire:          Interesting. That's something I haven't really thought about. We always just kind of use these mice to model athero and try to do it in the quickest way possible to get the papers out. But it's really interesting. Dr Coleen McNamara:    We use a lot of mouse models and we use young models with hypercholesterolemia in our laboratory as well. So I think that there's a real role for doing that. And a lot of people have really advanced the field with those types of models as well because they allow you to ask mechanistic questions. Dr Cindy St. Hilaire:          One of the things you mentioned in the paper was the variability of the IgMs produced, that there's not just one IgM, there's different flavors, I guess is a way to put it. Can you maybe just talk about that a little bit, what that might mean? And then I have another follow-up question after that. Dr Aditi Upadhye:            Sure. So B-1 cells, the B cell receptor, it's different on different B cells. And so that is made through a process called VDJ recombination. And the B cell receptor determines what your antibody is going to be specific for. There's a lot of different IgMs present within a given B cell repertoire because the differential combination of all these genes makes up the repertoire. Dr Cindy St. Hilaire:          What is it about the IgM that makes it atheroprotective, what's it actually targeting? Dr Aditi Upadhye:            That's a great question. So Dr Witztum and colleagues and others have shown that these IgMs target oxidation specific epitopes. And for example, one of them that we focus on in this paper is malondialdehyde-modified LDL. And so these IgMs can recognize MDA and either facilitate its clearance or prevent it from being bound to macrophages and prevent inflammatory processes within those macrophages downstream. Dr Cindy St. Hilaire:          So essentially this IgM is kind of working to prevent foam cell formation? Dr Aditi Upadhye:            Yes. Dr Cindy St. Hilaire:          Excellent. Dr Coleen McNamara:    So these are, these modified lipids are danger associated molecular patterns, as you've heard about before. So not only are these modified lipids taken up into the macrophage by scavenger receptors, which we know is an atherogenic, a process that leads to atherosclerosis, but they can also activate inflammatory pathways through toll-like receptors. Dr Cindy St. Hilaire:          So in light of the variability, I guess what I'm wondering is, is there more variability in these IgMs based on atherosclerotic state or in humans, healthy or control, and then also how are these heterogeneous populations of cells, how does your finding coincide with the recent studies on clonal hematopoiesis? And I was wondering if you could talk a little bit about that. Actually, for people who don't know, the idea... I guess I should explain the idea of clonal hematopoiesis. So essentially there was a recent paper in Science by Ken Walsh, who's actually at UVA now, where they found that there's acquired mutations in hematopoietic stem cells, and as we age, those mutations can become enriched and therefore somewhat clonal, hence the term clonal hematopoiesis. So how does the variability of the B cell population kind of work with this clonal hematopoiesis theory? Dr Coleen McNamara:    Well, it's interesting that you ask that because that's actually another direction within the lab. So we're collaborating with Dr Walsh and Jose Fuster, who was the first author on that Science paper. And we think, and in particular related to Aditi's work, that this particular subset of B cells has quite a propensity for clonality. And what she was actually able to show is, in terms of the B-1a cells within the peritoneal cavity, when their complementarity determining region three was sequenced, which is the main region responsible for recognizing the antigen-in 70% of the single cells that were sequenced, it was identical. So that actually is quite clonal. Dr Cindy St. Hilaire:          Yeah. So essentially if it was random, you would expect those numbers to be much lower. Much more variable. Dr Coleen McNamara:    Absolutely. But yet in the bone marrow, we saw much less of any given sequence being overrepresented. And in addition, there was evidence that there was modification in the antibody repertoire in adult life. Sort of suggesting and getting back to your earlier questions, that it actually may be atherogenic stimuli or hyperlipidemia that could be stimulating selection of other B cell clones. Dr Cindy St. Hilaire:          Interesting. So we have a lot of chicken and egg questions to ask for the future. Dr Coleen McNamara:    Yeah, exactly. And we're really getting into that space because we do think that the subtype of immune cell lends itself to clonal expansion. Dr Cindy St. Hilaire:          I guess I want to end with one question about the translatability of some of your findings. So the last figure, figure seven, you show an inverse relationship between the level of CXCR4 on these B-1 cells with increasing plaque burden. And essentially I think the analysis you did suggests that it was actually very predictive, even more so than lipid levels. So is there base for this as a biomarker of sorts do you think moving forward? Dr Aditi Upadhye:            Yeah, I think that's how we'd like to move forward in the lab is to look at how CXCR4 might be atheroprotective on these B-1 cells. And if we can find a good preclinical model to test that and see how it's atheroprotective in a more mechanistic way, that would be great. I think also that our ability to show that increasing CXCR4 on mouse B-1 cells and getting them to increase their localization to the bone marrow and increase IgM production, that also indicates that this could be feasible. But whether or not that can be atheroprotective is a question for the future. Dr Cindy St. Hilaire:          That's great. Well thank you so much for taking the time speaking with me today. This was an amazing story with very cool implications for the future, and Aditi, I look forward to following your bright career in the future. Dr Aditi Upadhye:            Thank you so much for the opportunity. Dr Coleen McNamara:    Thank you. Dr Cindy St. Hilaire:          Thank you. Well, that's it for our highlights from the October 25th and November 8th issues of Circulation Research. Thank you so much for listening. This podcast is produced by Rebecca McTavish, edited by Melissa Stoner, and supported by the Editorial team of Circulation Research. Some of the copy texts for the highlighted articles was provided by Ruth Williams, and I'm your host, Dr Cindy St. Hilaire, and this is Discover CircRes, your source for the most up to date and exciting discoveries in basic cardiovascular research.  

A virtual roundtable discussion with noted investigators Prof Meletios A Dimopoulos and Dr Steven P Treon for a review of recent innovations in the treatment of Waldenström Macroglobulinemia. Pathophysiology, symptoms and common genetic mutations associated with Waldenström macroglobulinemia (WM) (00:00) Somatic mutations in MYD88 (L265P) and CXCR4 and implications for prognosis and therapy (1:46) Diagnostic criteria for WM (7:12) Case (Dr Treon): A man in his late 60s with WM experiences an IgM flare and worsening peripheral neuropathy during first-line treatment with rituximab (8:55) Indications for the initiation of therapy for patients with WM (12:02) Management approach for patients with WM experiencing IgM flare after treatment with rituximab (13:40) Activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib alone or in combination with rituximab in patients with WM (15:35) Perspective on the use of ibrutinib with or without rituximab as front-line therapy for WM (17:51) Symptoms and management of hyperviscosity syndrome associated with WM (21:07) Role of obinutuzumab in the management of WM (23:58) Case (Prof Dimopoulos): A man in his early 50s with WM and a MYD88 L265P mutation attains a very good partial response to first-line therapy with bortezomib/dexamethasone/rituximab (25:24) Selection of therapy for patients with WM in the first-line setting (27:50) Efficacy and tolerability of proteasome inhibitors for WM (31:42) Peripheral neuropathy associated with WM and implications for therapy (34:39) Duration of ibrutinib therapy for WM and impact of treatment holidays (37:27) Side effects associated with ibrutinib; monitoring and management of atrial fibrillation (39:44) Case (Dr Treon): A woman in her mid-60s diagnosed with WM and a MYD88 L265P mutation experiences a dramatic response after receiving ibrutinib as first-line therapy (44:44) Response and tolerability with ibrutinib in the front-line setting (46:56) Case (Prof Dimopoulos): A woman in her early 80s with a history of hypertension and atrial fibrillation is diagnosed with WM with a MYD88 L265P mutation and receives ibrutinib and anticoagulation therapy (49:39) Perspective on the use of ibrutinib for elderly patients and those with a history of atrial fibrillation (51:37) Activity of the BTK inhibitor zanubrutinib in patients with WM (54:36) Results of the Phase III iNNOVATE trial evaluating ibrutinib with rituximab versus rituximab alone for patients with previously untreated or relapsed/refractory WM (56:19) Ongoing investigation of CXCR4 inhibitors and the Bcl-2 inhibitor venetoclax for WM (57:59) Biologic rationale and role for venetoclax in WM (1:00:28) Tumor lysis syndrome associated with venetoclax  (1:04:11) Novel agents and approaches under investigation for WM (1:05:26) Therapeutic options for patients with WM after disease progression on ibrutinib (1:06:56) Select publications  

Title - Screening of cancer tissue arrays identifies CXCR4 on adrenocortical carcinoma: correlates with expression and quantification on metastases using 64Cu-plerixafor PET Abstract - Expression of the chemokine receptor CXCR4 by many cancers correlates with aggressive clinical behavior. As part of the initial studies in a project whose goal was to quantify CXCR4 expression on cancers non-invasively, we examined CXCR4 expression in cancer samples by immunohistochemistry using a validated anti-CXCR4 antibody. Among solid tumors, we found expression of CXCR4 on significant percentages of major types of kidney, lung, and pancreatic adenocarcinomas, and, notably, on metastases of clear cell renal cell carcinoma and squamous cell carcinoma of the lung. We found particularly high expression of CXCR4 on adrenocortical cancer (ACC) metastases. Microarrays of ACC metastases revealed correlations between expression of CXCR4 and other chemokine system genes, particularly CXCR7/ACKR3, which encodes an atypical chemokine receptor that shares a ligand, CXCL12, with CXCR4. A first-in-human study using 64Cu-plerixafor for PET in an ACC patient prior to resection of metastases showed heterogeneity among metastatic nodules and good correlations among PET SUVs, CXCR4 staining, and CXCR4 mRNA. Additionally, we were able to show that CXCR4 expression correlated with the rates of growth of the pulmonary lesions in this patient. Further studies are needed to understand better the role of CXCR4 in ACC and whether targeting it may be beneficial. In this regard, non-invasive methods for assessing CXCR4 expression, such as PET using 64Cu-plerixafor, should be important investigative tools. Full text - http://bit.ly/2hwPKOq Facebook - bit.ly/2xznxjV Twitter - bit.ly/2xzWvsu LinkedIn - bit.ly/2xzJ6kc Pintrest - bit.ly/2xzX8SS Reddit - bit.ly/2hoxI0N www.Oncotarget.com

Dr. Carolyn Lam:               Welcome to Circulation On The Run, your weekly podcast summary and backstage pass to the journal and its editors. I'm Dr. Carolyn Lam, associate editor from the National Heart Center and Duke National University of Singapore. Our journal this week features an in-depth review on transcatheter therapy for mitral regurgitation, a very, very hot and interesting topic. You have to listen on, coming up right after these summaries.                                                 Our first original paper this week sheds light on the influence of aging on aldosterone secretion and physiology. First author Dr. Nanba, corresponding author Dr. Rainey and colleagues from the University of Michigan in United States, examine the relationship between age and adrenal aldosterone synthase in 127 normal adrenals from deceased kidney donors. The donors' ages ranged from nine months to 68 years. The authors found that adrenals from older individuals displayed less normal aldosterone synthase expression and zona glomerulosa, and greater content of abnormal foci of aldosterone synthase expressing cells.                                                 Furthermore, older age was independently associated with dysregulated and autonomous aldosterone physiology, in an ancillary clinical study of subjects without primary aldosteronism. This study therefore suggests that aging may be associated with a sub-clinical form of aldosterone excess and provides at least one potential explanation for age related cardiovascular risk.                                                 The next study shows, for the first time, that the chemokine receptor, CXCR4, in vascular cells, limits atherosclerosis. The CXCL12 and CXCR4 chemokine ligand receptor axis is known to control cell homeostasis and trafficking. However, its specific in atheroprotection has thus far been unclear. This is addressed in today's study by first author Dr. During, corresponding author Dr. Weber, and colleagues of The Institute for Cardiovascular Prevention in Munich, Germany. In hyperlipidemic mice, the authors showed that cell-specific deletion of CXCR4 in arterial endothelial cells, or smooth muscle cells, marked the increase atherosclerotic lesion formation. Mechanistically, CXCR4 axis promoted endothelial barrier function through VE-cadherin expression and a stabilization of junctional VE-cadherin complexes. In arterial smooth muscle cells, CXCR4 sustained vascular reactivity responses, and a contractile smooth muscle cell phenotype. Whereas, CXCR4 deficiency favored the occurrence of macrophage-like smooth muscle cells in atherosclerotic plaques and impaired cholesterol efflux.                                                 Finally, in humans, the authors identified a common allele variant within the CXCR4 locus that was associated with reduced CXCR4 expression in carotid RG plaques, and increased risk for coronary heart disease. Thus, the study suggests that enhancing the atheroprotective effect of arterial CXCR4 by selective modulators may open normal therapeutic options in atherosclerosis.                                                 The next paper is the first to study the effects of rosuvastatin on carotid intima-media thickness in children, with heterozygous familial hypercholesterolemia. First author Dr. Braamskamp, corresponding author Dr. Hutten, and colleagues from Academic Medical Center Amsterdam in the Netherlands, study children with heterozygous familial hypercholesterolemia aged 6 to less than 18 years, with LDL cholesterol more than 4.9, or more than 4.1 millimoles per liter in combination with other risk factors, who received rosuvastatin for 2 years, starting at 5 milligrams once daily, with uptitration to 10 milligrams for children aged 6 to 10 years old, or 20 milligrams daily for those aged 10 to 18 years old.                                                 Carotid intima-media thickness was assessed by ultrasonography at baseline, 12 months and 24 months in all patients and in age-matched, unaffected siblings. Carotid intima-media thickness was measured at 3 locations, the common carotid artery, the carotid ball, and the internal carotid artery in both the left and right carotid arteries. At baseline, the mean carotid intima-media thickness was significantly greater for the 197 children with heterozygous familial hypercholesterolemia compared with the 65 unaffected siblings. Rosuvastatin treatment for 2 years resulted in significantly less progression of increased carotid intima-media thickness in children with heterozygous familial hypercholesterolemia than in the untreated, or unaffected siblings. As a result, there was no difference in carotid intima-media thickness between the two groups after two years of rosuvastatin. These findings, therefore, support the value of early initiation of statin treatment for LDL cholesterol reduction in children with heterozygous familial hypercholesterolemia.                                                 The final study highlights the therapeutic potential of a novel alpha calcitonin gene-related peptide for the treatment of heart failure. First author Dr. Aubdool, corresponding author Dr. Brain, and colleagues from King's College London in United Kingdom, tested the stable alpha analog of calcitonin gene-related peptide in 2 models ... First, an angiotensin 2 infused mouse, and secondly, pressure overload cardiac hypertrophy mouse model using suprarenal aortic ligation. They showed that systemic colon injection of the alpha analog blunted the angiotensin 2 induced rise in blood pressure, as well as the vascular and cardiac remodeling, changes in water consumption, and renal injury, that are normally associated with angiotensin 2 infusion. Furthermore, protective effects were also seen when starting the alpha analog treatment, only during the last week of the 2-week angiotensin 2 infusion, in other words, when hypertension was already established. Finally, the alpha analog preserved heart function, and diminished the degree of hypertrophy and fibrosis in the aortic ligation model.                                                 Thus, these results demonstrate the therapeutic potential of the alpha calcitonin gene-related peptide pathway, and the possibility that this injectable alpha analog may be effective in cardiac disease.                                                 Well, that wraps it up for this week's summaries! Now, for our featured discussion.                                                 For our feature discussion this week, we're talking about trans-catheter therapy for mitral regurgitation, a very hot field and a field in which there have been a lot of advances. To help us break it down, and get right into the insights, the challenges, and potential solutions, I am so pleased to have the first author of this in-depth review paper, Dr. Paul Sorajja from Minneapolis Heart Institute Foundation and Abbott Northwestern Hospital, as well as Dr. Manos Brilakis, associate editor from UT Southwestern, here with us today!                                                 Paul, could I start with you, and just ask you first to give us an idea of what we're talking about here when we talk about mitral regurgitation ... There are different kinds, which are we referring to, and what are the challenges involved in a trans-catheter therapy for mitral regurgitation? Dr. Paul Sorajja:                I think there are a number of challenges, I think the first thing is that MR is often thought of as one disease, but it's really an incredibly heterogeneous disease ... Broadly, we talk about primary versus secondary MR, but the mitral valve is so complex, with multiple different components, any one of which can disrupt and cause MR. When we're talking about trans-catheter therapy, it's often very easy, again, to think we could have one therapy that could treat a simply insufficient valve, but it's way more complex than that, and as a result, there have been many different approaches that have been developed, adding to the complexity of how we manage these patients. Dr. Carolyn Lam:               Right, and in your paper, I loved the way you grouped them, very logically, under those from mitral valve repair, and that for mitral valve replacement ... And then, under repair, you grouped it into leaflet versus targeting the LV ... Could you maybe give us some top-line insights on these techniques? Dr. Paul Sorajja:                Yeah, there are a number of different approaches that have mechanistically gone after the different components through the pathophysiology of MR, where there is leaflets, where there's analysts, cords, or ventricular approach ... I think it's somewhat simplistic to think of it that way, but as catheter-based technology, we are technically limited by what we can do from a catheter standpoint. I think it's inevitable to think about these catheter technologies as eventually being combined, rather than singular, in order to approach what surgeons do in the OR. Dr. Carolyn Lam:               Right, but then even going further, you spent quite a bit of the paper talking about trans-catheter mitral valve implantation ... So, replacing the mitral valve, that's really cool, could you tell us a bit about that, and about that important issue brought up about patient selection. Dr. Paul Sorajja:                Yes, it's a very good point, I think in terms of trans-catheter mitral replacement, I think that that's really where the future is going to go ... The simple analogy is that people think that it will follow the route of TAVR, but I think it will follow the route of TAVR more quickly so, because when you look at how the mitral valve is currently treated in the OR, sometimes, a lot of the times, patients can end up worse. Whereas, a trans-catheter solution actually, I think in terms of the safety margin, actually will equate a degree of safety relative to surgery, if it's done and developed correctly, as opposed to how TAVR's done. I think for TAVR, it's been a number of years for our field to be equivalent or superior to surgery, whereas I think with mitral, I think there's a lot of potential for mitral to have equated a degree of safety. As an example, in the Tendine Feasibility Study, it was published this past January ... A high-risk population, there was not a single procedure death, out of 30 patients ... And for these patients who would go to the OR with an eject fraction of 30 to 40 percent, I think that's quite remarkable. Dr. Carolyn Lam:               Wow, that's really exciting indeed! Manos, you handled this paper, and it's just so beautifully laid out ... That flow chart, I just want to refer all our listeners to the flow chart in Figure 7, that talks about maybe an approach that can be considered. Manos, could you share some thoughts on how this developed? Dr. Manos Brilakis:           Yeah, absolutely, and obviously Paul is the expert on this, but I think it's very important about this paper, and through discussions with Paul and through the development of the paper, is that there's more of a collaboration between the surgeons and the interventionists. So instead, if it's additional style of ... Or the interventionists are doing one thing and the surgeon is doing another, I think the key to success in the mitral field is working very closely together ... Many of those valves right now, the percutaneous valves, are done through a cut down and a typical approach, so working very closely to addressing the anatomic components of the mitral valve problem is a big plus.                                                 The other thing I think that is very important is the new emergence of imaging, trying to understand whether the new mitral valve is going to create issues with LVOT obstruction or not. I think that's leading to a whole new understanding of when and how patients are even candidates for this approach, and I think Paul can elaborate more on this, but as things evolve, fewer and fewer patients are going to be excluded from these new technologies. Dr. Carolyn Lam:               Paul, would you like to take that? What do you think is happening and will happen with patient selection? Dr. Paul Sorajja:                There has been a challenge in current feasibility studies, in terms of getting patients in, the anatomical restraints are exactly what Dr. Brilakis has outlined. There's a certain bulkiness and size to the valve, which essentially poses risk for LVOT obstruction if the valve is too big ... As a feasibility study that's still early, or a field that's still early in its development, there's been a really conservative approach in terms of patient selection to ensure that LVOT obstruction doesn't happen. I think we're pushing the boundaries for that, and I think we've learned a lot from CT imaging, in terms of predicting LVOT obstruction, and I think the valves are also getting to be shorter in profile, which makes it less likely ... But that is definitely one of the limitations, and it's a limitation that exists, not just for trans-cat therapy but also for surgical therapy. Dr. Carolyn Lam:               Right, and then maybe a question for both of you ... What do you think the future is going to hold? What do we need to make this more mainstream, and where do you think this will leave surgical approaches? I know you said a combined approach, but maybe you could elaborate a little bit more? Dr. Paul Sorajja:                I do think, and I agree, I think Manos' point is spot on about that ... This will have to be multidisciplinary, the surgeons and cardiologists absolutely need to continue to work together, that's what's led to the successful development of TAVR, and I think that will be even more so for mitral, because the mitral valve is just infinitely more complex, and we have a lot to learn from the surgeons. But I think going forward, the collaboration is going to be a requirement, and then the training is also going to be a significant portion ... Putting in a mitral valve is much more complex than putting in an aortic valve ... I think if there's a safety margin that's demonstrated, I still think that it will be more appealing and more rapidly adopted than aortic disease. Dr. Carolyn Lam:               Well, Manos? Dr. Manos Brilakis:           No, I completely agree with Paul on that respect. I think, in my mind, at least, an again, this is from an early standpoint, the next big step would be to make it completely percutaneous, right now, you still have to do the cut down, and it's a little more invasive, although still safer than the completely open surgery, but maybe having a complete percutaneous system would be the next big step ... There's no question in my mind, as well ... And watching very closely how Paul and the surgical team are handling this, I think this is definitely the way for the future. Sometimes, in TAVR, it's not as technically demanding, and you don't really need to have too many people in the room, but for this procedure, it's definitely more important to have everyone in the room, and benefit from everyone's expertise. Dr. Carolyn Lam:               Manos, could I switch tracks for a moment now, and ask you to comment on the question that I get a lot ... You're an Interventionist, you handle a lot of the interventional papers for Circulation, and a lot of people are wondering, what makes papers like Paul's ... What makes interventional papers something that we would want to publish in Circulation? Could you share some thoughts? Dr. Manos Brilakis:           Absolutely, thanks Carolyn ... That's a big part, I think, of the appeal of Circulation right now. We're really trying to communicate to people that cutting-edge, clinical science is actually at the heart and the core of Circulation, and clinical content is what drives a lot of editorial ... Especially in intervention, where particularly interesting and new, cutting-edge technologies, new trials, observational studies ... But essentially, things that are cutting-edge, and are going to have a specific implication and impact in the way the field is going ... And this is part of Dr. Sorajja's paper, showing where the future lies in terms of trans-catheter mitral technologies, but along the same lines, we love to have cutting-edge papers on various aspects ... Coronary, peripheral, all aspects of interventional cardiologies, as well as interventional imaging ... The goal, again is to make the submission easy, there are not many honors requirements for submitting the papers, it's very simple to submit, and there's an answer going out very quick, so we're looking forward to receiving more and more interventional papers on cutting-edge science. Dr. Carolyn Lam:               Thank you so much for joining us today, and don't forget to tune in again next week.  

[intro music]   Host – Dan Keller Hello, and welcome to Episode Thirty-Seven of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m your host, Dan Keller.   This week’s podcast features an interview with Jeanne Loring, who works with human induced pluripotent stem cells in a mouse model of MS. But to begin, we’d like to tell you about one of the most useful features of the MS Discovery Forum.   Each week somewhere between 30 and 110 papers related to multiple sclerosis are published in the scientific literature. At MSDF, we endeavor to list them all, publishing links to a curated set of each week’s new papers every Friday at msdiscovery.org/papers.   The first step in curating this list is an automated PubMed query that pulls all papers containing the terms multiple sclerosis, myelin, optic neuritis, acute disseminated encephalomyelitis, neuromyelitis optica, transverse myelitis, experimental autoimmune encephalomyelitis, cuprizone, neurodegeneration, microglia, and several related terms. This query returns many false positives. MSDF editors read all the titles and most of the abstracts and make judgments about which papers are directly relevant to MS or related disorders. Last week, for example, the query returned 139 papers and, in our judgment, only 58 of them – 42% – were truly MS-related. Some weeks the proportion is even lower than that.   The query terms neurodegeneration, myelin, and microglia are responsible for most of the false positives. Neurodegeneration, in particular, returns many references related to other neurodegenerative disorders, such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, stroke, and hypoxia, to name a few. Editorial judgments on which articles are relevant are often subjective, and we frequently struggle with those decisions. It’s easy to decide relevance when an article actually mentions multiple sclerosis. It’s harder when it mentions only myelin or only Th17 cells. If you think we’ve missed an important MS-related article—or if you think we’ve included an irrelevant article—I hope you’ll let us know by emailing us at editor@msdiscovery.org. And we’re open to suggestions on how to adjust our PubMed query to decrease false positives and false negatives.   Once we’ve chosen which of the articles to include in the week’s list, we select between two and four of them as Editors’ Picks. Those are the week’s articles that seem to us to be the most important or interesting or intriguing. Once again, we invite readers to take issue with our choices. We’d love to hear about important articles that we have not designated Editors’ Picks or, on the contrary, Editors’ Picks that don’t deserve the honor.   [transition music]   Now to the interview. Dr. Jeanne Loring is Professor of Developmental Neurobiology and Director of the Center for Regenerative Medicine at the Scripps Research Institute in San Diego. She and her collaborators have been testing human neural precursor cells derived from embryonic stem cells in a mouse model of MS. The cells are injected into the spinal cords of immunocompetent mice with a model of MS induced by a neurotropic hepatitis virus. The cells are rejected within a week, but in that time they suppress the immune system and induce remyelination.   Interviewer – Dan Keller In terms of how you came upon your most recent finding about human pluripotent stem cells in the mouse model of MS, could you give me a little bit of the back story?   Interviewee – Jeanne Loring Oh yeah, sure. It was really interesting. So Tom Lane and I set out to try to develop a stem cell therapy for MS using human cells. So as a control experiment, we took human pluripotent stem cells, in this case embryonic stem cells, and turned them into neural precursors; differentiated them just a little bit. And then we transplanted them into Tom’s mouse model of MS. These mice were not immunosuppressed, and so we expected the cells to be rejected. And this was just our first experiment. But the results were not what we expected. After the cells were rejected, the mice started getting better, and their clinical scores improved. And then after several months, these mice were almost indistinguishable from normal mice.   The first thing we thought was that we’d gotten the cages mixed up, and we were looking at something different. But we’ve repeated the experiment now more than a hundred times, and about 75% of the time we get the same result. So what this tells us is that these cells that we put into the animals are having some effect during the seven days that they exist in the animals that leads to both immunosuppression and remyelination and a clinical improvement which is quite remarkable.   MSDF When you say 75% of the time, does that mean you get almost no effect 25 % of the time? Or does it mean that 75% or the mice? Because that would say whether you’re making your stem cells right or not.   Dr. Loring It’s 75% of the mice.   MSDF How do you explain it at this point, or where do you go from here to find a way to explain it?   Dr. Loring So once we’d realized that we had a phenomenon that was repeatable, we realized that there was something special about these cells. And we tested other cell types, like the pluripotent stem cells that they were derived from, and human fibroblasts, and discovered that neither one of those was effective. And since then we’ve also tried other ways of making neural precursor cells, and those cells aren’t effective either. So it’s something extremely special about the cells that we used in these experiments, which is very lucky when you think about it.   So we’ve now, both Tom and I – even though we’re not in the same place – we’ve set out to try to find out what it is about these cells that gives them these properties. Our first sort of cut on this – our hypothesis – is that the cells are secreting something that has a lasting effect. Our sort of big picture idea is that there are probably more than one protein or glycoprotein being secreted. And together they suppress the immune system so they act on the inflammatory response so that they increase the number of regulatory T cells that are produced and decrease the other T cell types. And they induce remyelination.   So Tom is now working on trying to identify what factors these cells make that are inducing the T regulatory cells. And on my side, we’re trying to identify what it is that makes them remyelinate.   MSDF When you make these cells, how do you know you got a good batch? Can you characterize them? Are there biomarkers, and you can say, “We did it right this time?”   Dr. Loring Yes. In fact, that turns out to be really important because we did it wrong a few times. And we have a gene expression signature. It’s essentially diagnostic assay for this particular cell type. We’ve boiled it down to a set of qRT-PCR markers. And, because we have collaborators in Australia, we had to be able to transfer this quality control assay to them. So far it seems like those markers, I think it’s a group of 10 or 12 markers, seem to be predictive of the cells’ working in the animals.   MSDF And just to clarify, that’s real time quantitative polymerase chain reaction? How are you going about characterizing what they’re doing? I mean, are you doing cytokine measurements or you’re looking at cells that get produced in the mice?   Dr. Loring Tom is really handling the cells that get produced in the mouse. He’s doing the T cell analysis. What we’re doing, we developed an in vitro cell culture method to look for the effect of these cells on maturing oligodendroglia in culture. And we found that something secreted by these cells which shows up in their culture medium actually induces maturation of oligos – of OPCs – in vitro. I guess that’s another result that we didn’t expect to be quite so clear. So that shows that there’s something that is secreted by the cells. I mean, that’s the most likely idea. And on Tom’s side, he’s shown that the conditioned medium from the cells induces T-reg generation. And on our side, we’ve shown that conditioned medium from the cells induces oligo maturation.   So now we’re trying to figure out what it is in that conditioned medium because now we think we can do a cell-free therapy for MS if we can identify what the factors are. It would be much simpler for us to do even a protein therapy for MS than it is to do a cell therapy. So both sides are taking sort of a candidate gene approach in which we’re identifying the proteins that are most highly specifically expressed in the cells that work in the mice. We have a list of those proteins, and we’ve sort of snatched a few candidates out of that group, and we’re testing to see whether each one of those proteins in purified form has the same effect as the conditioned medium.   The other approach, which is more tedious but more likely to actually tell us what’s going on is for us to fractionate the medium into different sized proteins and then test each one of those fractions. We’re in the process of doing that right now.   MSDF But it sounds like these cells are pluripotent. Not pluripotent in the normal sense of a stem cell leading to different lineages, but they have a couple of effects. One is the immunomodulatory, the other is regenerating oligodendrocytes. Do you think it really requires the gamish of proteins? If you fractionate them, will you possibly lose the signal? And that’s a big matrix to put back together again.   Dr. Loring Yes, it is. And obviously, if we get no signal from our fractions, we’ll put our fractions back together again and try to find out whether – there are only three fractions, really, right now. So we’ll try different combinations of these fractions to try to find out if we can reproduce the effect. The effect is quite robust. We essentially get no maturation in medium conditioned by other cell types, but we get very strong maturation when we use conditioned medium from this particular neural precursor cell.   MSDF If you only have three fractions now, is it because you just have chosen not to fractionate it even more until you know what’s going on?   Dr. Loring Yes, we’re trying to hone in on it. So we don’t want too many different things to look at right away. I’m hoping that we find that only one of those fractions works, and that we can discover everything is within that fraction, but I really can’t predict what’s going to happen.   MSDF It sounds like the approach would be to put everything in except one each time as opposed to keep adding back. You’ve got to find the one critical one missing that makes the thing not work.   Dr. Loring Yes, and eventually we will do that with specific antibodies, but right now that is, since we don’t really have our candidates narrowed down enough, that isn’t a viable approach. But you’re absolutely right. We want to find out if that’s missing, whatever the things that are that are missing. And I’m hoping it’s not so complex that it’s five or six or seven proteins, because that’ll make it much harder for us.   MSDF How do characterize the condition of the mice?   Dr. Loring So that’s Tom’s area of expertise. It’s essentially an observation of the mice over time. We have a movie which I can show you, but I can’t actually do it in a recording. It’s quite obvious when the mice – they’re blind scored so the person who looks at the mice and sees how well they’re walking around doesn’t know whether they’re controls or experimentals. If you just see the movies that are selected at particular times after the cells have been transplanted, it’s quite dramatic. They have a much better clinical score. Essentially, they’re almost normal after six months.   MSDF And how are you sure that the cells you injected into the spinal cord are gone, that they’ve been rejected completely?   Dr. Loring That’s a good question. We used a method for live imaging of cells in which we use luciferase to label the cells. And then we used an instrument which allows us to image the cells in mice – in living mice – over time. So we did this in individual mice and saw that they disappeared over time. And after eight days we couldn’t detect them anymore. That doesn’t mean there isn’t one or two left because the resolution isn’t that high. We will go back eventually and look through sections of the spinal cords and see whether we can detect any. The other thing we can do is (skip 13:37) a human-specific markers. So we can just take a section of the spinal cord and find out if there’s any human cells in it at all, or any human genes in it at all. But we haven’t done that yet.   MSDF Do the cells have to be gone? Have you tried injecting a second time?   Dr. Loring No, we haven’t. We don’t know. We really don’t know. It would be very interesting if it reversed the effects. Then we’d really have a problem to solve.   MSDF What else is there important to add or that we’ve missed that’s important to this kind of research?   Dr. Loring So our dream is that we will identify a group of proteins and the concentration of those proteins necessary to have these two effects in this mouse model. And then we will do some biological engineering. We’ll be putting the cells into these little spheres and matrix that allows slow release of these proteins or controlled release of these proteins. And then, instead of putting cells in, we’ll put these beads in. And I don’t know whether that would end up being the final product or not, but there are lots of ways to deliver proteins, and this one I find rather attractive because it doesn’t require pumps or syringes. And I think that’s certainly the direction we’re going to try to go in. And so Tom Lane and I have just gotten an NIH grant for five years of funding, which seems like a very long time to me. So in five years we will have discovered the best way to deliver these things. We’ll discover what they are and the best way to deliver them. Tom has put conditioned medium into the mice, and it also works.   MSDF Because I was going to ask, had you encapsulated the cells just to see that the supernatant does it without cell contact?   Dr. Loring It turns out that the conditioned medium itself, you inject that into spinal cord, it’s not as dramatic an effect, but you have a clear clinical improvement.   MSDF Have you tried injecting it either IV or intraperitoneally?   Dr. Loring Yes. Well, we didn’t inject the conditioned medium. We did try injecting the cells, and they pretty much stayed where we injected them. These cells, unlike mesenchymal stem cells, they aren’t very migratory. So they don’t really have the receptors that cause them to move to areas of inflammation like CXCR4, for example; they don’t express that on their surfaces. So that does not seem to be a good delivery method for these cells. They don’t go anywhere.   MSDF I was also thinking that if something they secrete is important, whether it circulates. Maybe they’re not making enough concentration if you inject them outside of the central nervous system, but it seems like you’re going to be faced with a little cumbersome problem in a clinical situation years and years ahead from now if you have to keep injecting proteins into the spinal cord as opposed to more peripheral.   Dr. Loring I agree. And the solution to that is generally to look for peripheral effects and then try to suppress those when you do a therapy like this. That’s a long time, and we could certainly imagine how we would do it. But we need to know what those proteins are before we can decide on whether we expect them to have effects peripherally or not. But I agree with you; delivering them intravenously would be far easier.   MSDF I know you have a lot of work ahead of you now with this, but is there another animal model of MS – or even another mouse model of MS – where you can see if it works even in a mouse model different from this one?   Dr. Loring Yes, we’re actively pursuing that with our collaborators in Australia. And it’s interesting because they’ve gotten some positive preliminary results using the EAE model, but the approach to the EAE model I’ve realized is quite different. Generally, what people do is they provide the therapy at the time that the pathology is developing, and they try to prevent it, which is a really different idea than what we had using the mice that are already paralyzed. So they have found that if you can deliver the cells at least close to the spinal cord, then you can see some effects. The problem is that in Australia, and this is one of those technical things we had not anticipated, they don’t have permission to inject cells into the spinal cord. So they have to go through their animal rights people or their animal protection groups and try to get permission to do so. So with Craig Walsh at UC Irvine we have started doing parallel experiments with the EAE model. I’m not necessarily sure that it’s going to have similar effects. I mean, I really don’t know.   MSDF Can you describe how these mice in your experiments were made to have MS?   Dr. Loring Yes, they were given a virus, a neurotropic virus, which kills off the oligodendroglia. They become demyelinated, and there is a secondary inflammatory response. So the mice are actually paralyzed in their hind quarters at least by the time we put the cells in. They have to be fed by hand. So this is not a trivial thing to do. But we’re trying to reproduce the effects during the progressive form of MS, for example, or during an attack of MS. So we’re trying to repair the mice or cure the mice that are in a condition which would be similar to the worst case scenario for people with MS.   MSDF Do you think this may also have effects not only on the myelin, but also on damaged neurons?   Dr. Loring We don’t know, because the mice haven’t really had enough time to get a lot of neuronal damage, but that’s a very good question. We don’t know yet.   MSDF I appreciate it. Thank you.   Dr. Loring You’re welcome. It was a pleasure.   [transition music]   Thank you for listening to Episode Thirty-Seven of Multiple Sclerosis Discovery. This podcast was produced by the MS Discovery Forum, MSDF, the premier source of independent news and information on MS research. MSDF’s executive editor is Robert Finn. Msdiscovery.org is part of the non-profit Accelerated Cure Project for Multiple Sclerosis. Robert McBurney is our President and CEO, and Hollie Schmidt is vice president of scientific operations.   Msdiscovery.org aims to focus attention on what is known and not yet known about the causes of MS and related conditions, their pathological mechanisms, and potential ways to intervene. By communicating this information in a way that builds bridges among different disciplines, we hope to open new routes toward significant clinical advances.   We’re interested in your opinions. Please join the discussion on one of our online forums or send comments, criticisms, and suggestions to editor@msdiscovery.org.   [outro music]

Background To overcome the limitations of animal-based experiments, 3D culture models mimicking the tumor microenvironment in vivo are gaining attention. Herein, we investigated an alginate-based 3D scaffold for screening of 5-fluorouracil (5-FU) or/and curcumin on malignancy of colorectal cancer cells (CRC). Methods The potentiation effects of curcumin on 5-FU against proliferation and metastasis of HCT116 cell and its corresponding isogenic 5-FU-chemoresistant cells (HCT116R) were examined in a 3D-alginate tumor model. Results CRC cells encapsulated in alginate were able to proliferate in 3D-colonospheres in a vivo-like phenotype and invaded from alginate. During cultivation of cells in alginate, we could isolate 3 stages of cells, (1) alginate proliferating (2) invasive and (3) adherent cells. Tumor-promoting factors (CXCR4, MMP-9, NF-κB) were significantly increased in the proliferating and invasive compared to the adherent cells, however HCT116R cells overexpressed factors in comparison to the parental HCT116, suggesting an increase in malignancy behavior. In alginate, curcumin potentiated 5-FU-induced decreased capacity for proliferation, invasion and increased more sensitivity to 5-FU of HCT116R compared to the HCT116 cells. IC50 for HCT116 to 5-FU was 8nM, but co-treatment with 5 μM curcumin significantly reduced 5-FU concentrations in HCT116 and HCT116R cells (0.8nM, 0.1nM, respectively) and these effects were accompanied by down-regulation of NF-κB activation and NF-κB-regulated gene products. Conclusions Our results demonstrate that the alginate provides an excellent tumor microenvironment and indicate that curcumin potentiates and chemosensitizes HCT116R cells to 5-FU-based chemotherapy that may be useful for the treatment of CRC and to overcome drug resistance.

Interstitial lung diseases (ILD) are severe chronic lung diseases characterized by an increased deposition of extracellular matrix in the lung interstitial space, leading to a thickening of the alveolar walls and impairment of the gas exchange. One of the most common entities in this category is idiopathic pulmonary fibrosis (IPF) with a mean survival time of 2 to 3 years from diagnosis. Until now, there is no curative therapy available and the symptomatic anti- inflammatory treatment and oxygen supplementation cannot prevent the development of the end stage pulmonary fibrosis. The chemokine receptor CCR2 is important for leukocyte recruitment to inflamed tissues through interaction with CCL2 (MCP-1). The blockade of the CCR2/CCL2 pathway attenuated the development of pulmonary fibrosis in mouse models. However, CCR2+ T-lymphocytes acquired regulatory functions in experimental arthritis during the course of disease. Therefore, it is unknown whether CCR2+ T cells are involved in the pathogenesis of IPF or, on the contrary, represent an unsuccessful effort of the immune system to limit the disease. Observations in paediatric patients with different forms of ILDs suggested a role for CCR2+ T cells in pulmonary fibrosis. To characterize these T cells, flow cytometric studies were performed using the bleomycin mouse model of pulmonary fibrosis. The kinetic of CCR2+ T cells in BALF, lung tissue, and spleen following intratracheal administration of bleomycin (BLM) was assessed at time points between day 3 and day 21. To determine, if the constellation of naïve, central memory and effector memory T cells changes after BLM treatment, and to which of these subtypes CCR2+ T cells belong to, the cells were additionally stained for CD62L and CD44. For further characterization of CCR2+ T cells, chemokine receptor co-expression with CCR2 was investigated at the time point of the maximal presence of CCR2+ T cells. Total T cell numbers increased in BAL and lung tissue but not in spleen. Percentages of CD62LlowCD44hi effector memory T cells increased in lung tissue in the early phase of BLM induced fibrosis, while the CD62LhiCD44low naïve T cell population decreased. The percentage of CCR2+ T cells increased following BLM treatment with a maximum on day 12. The majority of CCR2+CD4+ T cells showed a Tem phenotype. CCR3, CCR4, CCR6, CXCR4, and CXCR5 expressing cells increased within the pulmonary CD4+ T cell population following bleomycin treatment. Among CD8+ T cells from treated mice, CCR5, CCR6, and CXCR5 positive cells were increased. CCR7 was highly co-expressed with CCR2 in saline and bleomycin treated mice, whereas co-expression of CCR3, CCR4, CCR6 and CXCR5 increased significantly in treated mice. The results indicate an activation of pulmonary T cell populations following bleomycin treatment. CCR2+CD4+ T cells probably take part on this T cell response as they exhibit an effector memory phenotype and increase following BLM treatment. In contrast, the stable percentages of the different T cell subtypes in spleens gave no hint for a systemic T cell reaction. The pattern of chemokine receptor expression argues against a Th1 polarization and towards a Th2, Th17 or TFH polarization of CCR2+ T cells.

The clinical course of renal cell carcinoma (RCC) shows a high variability. Prognostic markers are essential to enable an individualized therapeutic strategy. The objective of this study was the identification of novel independent prognostic markers and potential therapeutic targets in RCC. The focus was on genes involved in epithelial-mesenchymal transition (EMT) and cancer stem cell biology. EMT enhances tumor cell motility and hence plays a critical role in invasion and metastasis in various carcinomas. A set of transcription factors acts as master regulators of EMT. Whether EMT is important for tumor progression in clear cell renal cell carcinoma (RCC) is unknown. Therefore, EMT-related genes were selected from the literature, and their role and prognostic relevance in RCC were analyzed. The known cancer stem cell marker CXCR4 and the associated TPBG gene were also analyzed in this project. Additionally, a novel filter strategy was used to analyze RCC oligonucleotide microarray data for identification of potential prognostic markers: genes with increasing expression during tumor progression (normal kidney < primary tumor < metastases) were selected for outcome analysis because they could be crucial for RCC biology. Expression of 46 EMT-related genes was analyzed using oligonucleotide microarrays and gene set enrichment analysis (GSEA) in tissue samples from normal kidney and G1 and G3 primary RCC, 14 samples each. Expression of selected EMT genes was validated by real-time polymerase chain reaction (PCR) in normal kidney, primary RCC and metastases in an independent cohort of 112 patients and then combined with follow-up data for survival analysis. Immunohistochemistry, Western blot and flow cytometry were performed to further examine the expression of CXCR4 and co-expression of CXCR4 and TPBG on the surface of RCC cells. GSEA and dChip software were used for microarray data analysis. The EMT gene set was preferentially expressed in primary tumors compared to normal tissue (false discovery rate FDR=0.01), but no difference between G1 and G3 tumors was found. Quantitative RT-PCR showed down-regulation of critical EMT genes like CDH2 and ZEB1 in metastases which suggests reversal of EMT during metastasis. Kaplan-Meier analysis demonstrated a significant better outcome for patients with low CXCR4, vimentin, fibronectin and TWIST1 mRNA levels. Multivariate analysis revealed that CXCR4 and vimentin up-regulation represent independent prognostic markers for poor cancer-specific survival of RCC patients. The microarray approach using filtering and further RT-PCR validation of progression-associated genes revealed that ATAD2, TET3, HELLS and TOP2A are independent and previously unknown predictors of poor outcome in RCC patients. Taken together, this study provides strong evidence that EMT occurs in RCC. Modulation of EMT in RCC, therefore, might represent a future therapeutic option. Expression levels of a number of EMT-related genes (like the genes encoding the cancer stem cell marker CXCR4 and vimentin) could be identified as independent prognostic markers. Using a novel filtering approach on array data, additional novel prognostic markers could be identified. These findings contribute to a better risk stratification of RCC patients that can support an individualized and optimized therapeutic strategy.

Sat, 9 Feb 2013 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/15765/ https://edoc.ub.uni-muenchen.de/15765/1/Busalt_Florian_Christopher.pdf Busalt, Florian Christopher ddc:590, ddc:500, Tierärztlic

Activation of the small GTPase Rho downstream of a chemokine receptor is required for metastasis of some breast cancer cells.

CXCR7 (RDC1), the recently discovered second receptor for CXCL12, is phylogenetically closely related to chemokine receptors, but fails to couple to G-proteins and to induce typical chemokine receptor mediated cellular responses. The function of CXCR7 is controversial. Some studies suggest a signaling activity in mammalian cells and zebrafish embryos, while others indicate a decoy activity in fish. Here we investigated the two propositions in human tissues. We provide evidence and mechanistic insight that CXCR7 acts as specific scavenger for CXCL12 and CXCL11 mediating effective ligand internalization and targeting of the chemokine cargo for degradation. Consistently, CXCR7 continuously cycles between the plasma membrane and intracellular compartments in the absence and presence of ligand, both in mammalian cells and in zebrafish. In accordance with the proposed activity as a scavenger receptor CXCR7-dependent chemokine degradation does not become saturated with increasing ligand concentrations. Active CXCL12 sequestration by CXCR7 is demonstrated in adult mouse heart valves and human umbilical vein endothelium. The finding that CXCR7 specifically scavenges CXCL12 suggests a critical function of the receptor in modulating the activity of the ubiquitously expressed CXCR4 in development and tumor formation. Scavenger activity of CXCR7 might also be important for the fine tuning of the mobility of hematopoietic cells in the bone marrow and lymphoid organs.

Aims: The mobilization of endothelial progenitor cells (EPC) and their functioning in postnatal neovascularization are tightly regulated. To identify new modulators of EPC homeostasis, we screened biologically active prostaglandin E compounds for their effects on EPC production, trafficking and function. Methods and Results: We found that EPC are a rich source for prostaglandin E 2 (PGE 2), stimulating their number and function in an auto- and paracrine manner. In vivo blockade of PGE 2 production by selective cyclooxygenase-2 inhibition virtually abrogated ischemia-induced EPC mobilization demonstrating its crucial role in EPC homeostasis following tissue ischemia. Conversely, ex vivo treatment of isolated EPC with the clinically approved PGE 1 analogue alprostadil enhanced EPC number and function. These effects were mediated by increased expression of the chemokine receptor CXCR4 and were dependent on nitric oxide synthase activity. Most importantly, ex vivo PGE 1 pretreatment of isolated EPC significantly enhanced their neovascularization capacity in a murine model of hind limb ischemia as assessed by laser Doppler analysis, exercise stress test and immunohistochemistry. Conclusions: The conserved role for PGE in the regulation of EPC homeostasis suggests that ex vivo modulation of the prostaglandin pathway in isolated progenitor cells may represent a novel and safe strategy to facilitate cell-based therapies. Copyright (C) 2009 S. Karger AG, Basel

The bacteria that cause gingivitis evade destruction by promoting crosstalk between two receptors that regulate the immune response.

„Placebo-controlled double-blind treatment study in naturally Feline Immunodeficiency Virus-infected cats using the chemokine receptor inhibitor 1,1’-bis-1,4,8,11-tetraazacyclotetradekan (AMD3100)“ Antiretroviral efficacy of the bicyclam 1,1’-bis-1,4,8,11-tetraazacyclotetradekan (AMD3100) alone or in combination with the acyclic nucleoside phosphonate (R)-9-(2-phosphonylmethoxyethyl)adenine (PMEA) was investigated. Forty naturally FIV-infected cats were treated for a period of 6 weeks in a placebo-controlled double-blind study. Patients were randomly classified into 4 treatment groups, “Placebo”, “AMD”, “PMEA”, and “AMD/PMEA”. Placebo or the compounds AMD3100 (0,5 mg/kg body weight) and PMEA (10 mg/kg body weight) were administered subcutaneously twice a day or twice a week, respectively. Side effects of treatment with PMEA were a statistically significant decrease in the erythrocyte count, the hemoglobin concentration, the packed cell volume, and the number of neutrophil granulocytes. PMEA treatment caused a statistically significant improvement in the inflammation of the oral cavity. AMD3100 showed no clinical side effects. Serum magnesium levels decreased statistically significant with AMD treatment without causing clinical sings. Cats in the AMD group showed a statistically significant decrease of the proviral load. Therefore, AMD3100 had a clear antiviral efficacy against FIV. Side effects were not causing clinical sings and the bicyclam should be tested over a longer treatment period. Combination of both substances did not exacerbate side effects of either component. There was a decrease in proviral load in cats receiving only AMD3100 while no decrease was observed in combination with PMEA. PMEA-induced immunomodulation possibly inhibited the mechanism of action of AMD3100. T cell activation and proliferation of latently infected T cells were potentially stimulated during PMEA treatment leading to insufficient blockage of CXCR4 by AMD3100 that would prevent infection of additional cells.