Podcasts about MYD88

In this week's podcast, a potential new therapeutic target in beta-thalassemia. The E3 ubiquitin ligase AMBRA1 promotes autophagic clearance of free alpha-globin. Researchers describe mutations in the AMBRA1 gene that impair this clearance, exacerbating ineffective erythropoiesis and disease severity. After that: targeting MYD88 mutations. Lasalocid-A is a compound that selectively binds to the MYD88 L265P mutant protein, which is found in a range of B-cell lymphomas. New research shows its potential to inhibit tumor growth, overcome ibrutinib resistance, and synergize with venetoclax. Finally: air pollution is linked to an increased risk of venous thromboembolism in a prospective, community-based cohort study. The findings highlight the harms of pollution, and support the case for global efforts to improve public health.Featured Articles:Mutations in AMBRA1 aggravate β-thalassemia by impairing autophagy-mediated clearance of free α-globinLasalocid A selectively induces the degradation of MYD88 in lymphomas harboring the MYD88 L265P mutationAir pollution is associated with increased risk of venous thromboembolism: the Multi-Ethnic Study of Atherosclerosis

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.02.08.527716v1?rss=1 Authors: Li, Y., Shah, R. B., Sarti, S., Belcher, A. L., Lee, B. J., Gorbatenko, A., Nemati, F., Yu, I., Stanley, Z., Shao, Z., Silva, J., Zha, S., Sidi, S. Abstract: Interleukin-1 receptor (IL-1R)-associated kinases (IRAKs) are core effectors of Toll-like receptor (TLR) and IL-1R signaling, with no reported roles outside of innate immunity. We find that vertebrate cells exposed to ionizing radiation (IR) sequentially activate IRAK4 and IRAK1 through a phosphorylation cascade mirroring that induced by TLR/IL-1R, resulting in a potent anti-apoptotic response. However, IR-induced IRAK1 activation does not require the receptors or the IRAK4/1 adaptor protein MyD88, and instead of remaining in the cytoplasm, the activated kinase is immediately transported to the nucleus via a conserved nuclear localization signal. We identify: double-strand DNA breaks (DSBs) as the biologic trigger for this pathway; the E3 ubiquitin ligase Pellino1 as the scaffold enabling IRAK4/1 activation in place of TLR/IL-1R-MyD88; and the pro-apoptotic PIDDosome (PIDD1-RAIDD-caspase-2) as a critical downstream target in the nucleus. The data delineate a non-canonical IRAK signaling pathway derived from, or ancestral to, TLR signaling. This DSB detection pathway, which is also activated by genotoxic chemotherapies, provides multiple actionable targets for overcoming tumor resistance to mainstay cancer treatments. 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/2022.09.09.507263v1?rss=1 Authors: PARASAR, P., Kaur, N., Poisson, L., Singh, J. Abstract: ABSTRACT Objective: The role of astrocytes largely remains to be explored in X-linked adrenoleukodystrophy (X-ALD). Due to limited study models and inaccessibility to patient-tissue samples, we differentiated astrocytes from patient fibroblast-derived induced pluripotent stem cell (iPSCs) which provided a unique system to investigate molecular and etiopathogenetic mechanisms, identify targets, and develop therapeutic agents for X-ALD. Methods: We reprogrammed fibroblasts from adrenomyeloneuropathy (AMN) and cerebral adrenoleukodystrophy (cALD) patients carrying ABCD1 with pathogenic variants and a control patient to generate iPSCs. We differentiated iPSCs into astrocytes and performed transmission electron microscopy, gene expression, immunoblotting, enzyme-linked immunosorbent assay, miRNA-Seq, and lipidomics to characterize phenotypic and molecular features of patient-derived astrocytes. Results: These differentiated astrocytes exhibit diseased phenotypes and replicate biochemical and molecular changes found in patients. We confirmed the deletion of ABCD1 gene-encoded ALD protein and identified ABCD1 variant-driven very long chain fatty acid deposition in AMN and cALD astrocytes. Especially, cALD astrocytes showed increased glycolysis, increased signal transducer and transcription activator (STAT)3 activation, higher miR-9 expression in miRNA-Seq analysis, and reduced expression of anti-inflammatory cytokines such as arginase-1 and mannose receptor C-type-1. Consequently, Toll-like receptor-signaling via myeloid differentiation primary response gene 88 (MyD88) and nuclear factor-kappa B (NF-{kappa}B; p52 and p65) induced STAT3 and an altered miR-9 expression is a potential contributor to inflammatory milieu in cALD while interleukin-6 -induced anti-inflammatory cytokine production and increased chemotactic CCL-2 (MCP-1) production in AMN potentially favors microglial recruitment protecting its further progression. Interpretation: We demonstrate for the first time that patient iPSC-derived astrocytes mimic and recapitulate neuroinflammatory and biochemical defects of X-ALD and provide an in vitro cellular system to study X-ALD. Copy rights belong to original authors. Visit the link for more info Podcast created by PaperPlayer

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2022.09.06.506660v1?rss=1 Authors: Akeret, K., Buzzi, R. M., Thomson, B. R., Schwendinger, N., Klohs, J., Schulthess, N., Baselgia, L., Hansen, K., Regli, L., Vallelian, F., Hugelshofer, M., Schaer, D. Abstract: The functional neurological outcome of patients with intracerebral hemorrhage (ICH) strongly relates to the degree of secondary brain injury (ICH SBI) evolving within days after the initial bleeding. Different mechanisms including the incitement of inflammatory pathways, dysfunction of the blood brain barrier (BBB), activation of resident microglia, and an influx of blood-borne immune cells, have been hypothesized to contribute to ICH SBI. Yet, the spatiotemporal interplay of specific inflammatory processes within different brain compartments has not been sufficiently characterized, limiting potential therapeutic interventions to prevent and treat ICH SBI. Using a whole-blood injection model in mice, we systematically characterized the spatial and temporal dynamics of inflammatory processes after ICH using 7 Tesla magnetic resonance imaging (MRI), spatial RNA sequencing (spRNAseq), functional BBB assessment, and immunofluorescence average intensity mapping. We identified a pronounced early response of the choroid plexus (CP) peaking at 12 to 24h, that was characterized by inflammatory cytokine expression, epithelial and endothelial expression of leukocyte adhesion molecules, and the accumulation of leukocytes. In contrast, we observed a delayed secondary reaction pattern at the injection site (striatum) peaking at 96h, defined by gene expression corresponding to perilesional leukocyte infiltration and correlating to the delayed signal alteration seen on MRI. Pathway analysis revealed a dependence of the early inflammatory reaction in the CP on toll-like receptor 4 (TLR4) signaling via myeloid differentiation factor 88 (MyD88). TLR4 and MyD88 knockout mice corroborated this observation, lacking the early upregulation of adhesion molecules and leukocyte infiltration within the CP 24h after whole-blood injection. In conclusion, we report a biphasic brain reaction pattern after ICH with a MyD88 TLR4 dependent early inflammatory response of the CP, preceding inflammation, edema and leukocyte infiltration at the lesion site. Pharmacological targeting of the early CP activation might harbor the potential to modulate the development of ICH SBI. Copy rights belong to original authors. Visit the link for more info Podcast created by PaperPlayer

Dr. Linden Hu, Vice Dean for Research at Tufts University in Boston Massachusetts and Paul and Elaine Chervinsky Professor in Immunology, discusses new and ongoing research pertaining to the prevention, treatment and diagnosis of human Lyme disease. He also discusses some of the key unanswered questions about Lyme, such as how B. burgdorferi adapts to different hosts and environments and why some patients have been known to exhibit persistent symptoms even after treatment.   Links mentioned: Webinar - Vector-Borne Disease in a Changing Climate https://asm.org/Webinars/Vector-Borne-Disease-in-a-Changing-Climate The Bulls-Eye Rash of Lyme Disease: https://asm.org/Articles/2018/April/going-skin-deep-investigating-the-cutaneous-host-p Pfizer and Valneva Initiate Phase 3 Study of Lyme Disease Vaccine Candidate VLA15 https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-valneva-initiate-phase-3-study-lyme-disease Could This Treatment Prevent Chronic Lyme Disease? https://news.northeastern.edu/2021/10/06/preventing-chronic-lyme-disease/ Promising New Drug Would Eradicate Lyme While Leaving Gut Microbes Alone: https://www.lymedisease.org/members/lyme-times/2022-spring-news/targeted-lyme-disease-drug/ A Tick's Meal: https://asm.org/Podcasts/TWiM/Episodes/A-Tick-s-Meal-TWiM-258 Evidence That the Variable Regions of the Central Domain of VlsE Are Antigenic during Infection with Lyme Disease Spirochetes https://journals.asm.org/doi/10.1128/IAI.70.8.4196-4203.2002 Distinct Roles for MyD88 and Toll-Like Receptors 2, 5, and 9 in Phagocytosis of Borrelia burgdorferi and Cytokine Induction https://journals.asm.org/doi/10.1128/IAI.01600-07

This week, please join author Kory Lavine and Associate Editor Thomas Eschenhagen as they discuss the article "Donor Macrophages Modulate Rejection After Heart Transplantation." 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:           I'm Dr. Greg Hundley, associate editor and director of the Pauley Heart Center at VCU Health in Richmond, Virginia. Well, Carolyn, this week's feature, we are going to the world of preclinical science and we are going to learn about a very important new finding pertaining to heart transplant rejection, and macrophages may modulate this, but before we get to that feature, how about we grab a cup of coffee and go through some of the other articles in the issue? Dr. Carolyn Lam:             I got mine. Would you like to go first, Greg? Dr. Greg Hundley:           You bet, Carolyn. Well, my first study comes to us from Dr. Michael Pencino from Duke University. Carolyn, this study was performed to understand the predictive utility of a previously derived polygenic risk score for long-term risk of coronary heart disease and its additive value beyond traditional risk factors and how that might be able to inform prevention strategies. To accomplish this, data from adults aged 20 to 59 free of cardiovascular health disease from the Framingham Offspring Study and the Atherosclerosis Risk in Communities, or ARIC Study, were analyzed. Now, since the polygenic risk score was derived from people of predominantly European ancestry, individuals who self-reported white race were those that were included. Dr. Carolyn Lam:             Oh, interesting, so what did they find, Greg? Dr. Greg Hundley:           Right, Carolyn. Somewhat surprisingly, they found that, among 9,757 participants, both the traditional risk factor score and the polygenic risk score where significantly associated with incident cardiovascular heart disease in young, early midlife, and late midlife. Now, the delta C index, when the polygenic risk score was added to the traditional risk factor, score was 0.03, 0.02, and 0.002 in the young, the early midlife, and the late-midlife participants, respectively. Carolyn, despite a statistically significant association between the polygenic risk score and the 30-year risk of cardiovascular heart disease, the C index improved only marginally with the addition of the polygenic risk score to the traditional risk factor model among young adults and did not improve among midlife adults and, thus, Carolyn, the polygenic risk score, an immutable factor, has limited clinical utility for long-term cardiovascular heart disease prediction when added to a traditional risk factor model. Dr. Carolyn Lam:             I really like that, Greg, because I think it also tells us that the traditional risk factors, which we can do something about, are still very important. Isn't that great? Well, the next paper is about POTS. Remember what that is? Should I give you a quiz? All right. It's okay. POTS, or Postural Orthostatic Tachycardia Syndrome, is a disorder of orthostatic intolerance that primarily affects females of childbearing age. While the underlying pathophysiology of POTS is not fully understood, it has been suggested that autoimmunity may play a role. Now, the aim of this study was to compare concentrations of autoantibodies to cardiovascular G protein-coupled receptors between 116 POTS patients and 81 healthy controls, and they were from Calgary, Canada, and Malmo, Sweden. Dr. Greg Hundley:           Carolyn, really interesting, so what did they find here? Dr. Carolyn Lam:             The investigators, led by Dr. Raj from University of Calgary in Canada, found that commercially available autoantibody concentrations to G protein-coupled receptors were not increased or altered in POTS patients relative to healthy controls as assessed using ELISA. Now, while this study suggests that these G protein-coupled receptor autoantibody concentrations alone cannot explain the pathophysiology of POTS, autoantibody activity and signals not picked up by ELISA should still be explored as these results may provide more insights into the pathophysiology of POTS. Dr. Greg Hundley:           Very nice, Carolyn. Well, my next study comes to us from the world of pulmonary arterial hypertension. Carolyn, clinical worsening is commonly used as an endpoint in pulmonary arterial hypertension trials. These authors, led by Dr. Steeve Provencher from the Institut Universitaire de Cardiologie Pneumologie de Quebec, aimed to assess the trial-level surrogacy of clinical worsening for mortality in pulmonary artery hypertension trials and whether the various clinical worsening components were similar in terms of frequency of occurrence, treatment-related relative risk reduction and importance to patients. Dr. Carolyn Lam:             Okay, so what did they find? Dr. Greg Hundley:           Right, Carolyn, so they searched MEDLINE, Embase and the Cochrane Library for trials evaluating the effects of pulmonary arterial hypertension on clinical worsening and, among 35 independent cohorts, so 9,450 patients, the effects of pulmonary arterial hypertension-specific therapies on clinical worsening modestly correlated with mortality. Additionally, study-level clinical worsening was not found to be a surrogate for mortality in pulmonary arterial-hypertension trials. Moreover, components of clinical worsening largely vary in frequency, response to therapy and importance to patients and, thus, are not necessarily interchangeable. Dr. Carolyn Lam:             Thank you, Greg. Can I tell you about some other papers in today's issue? There's a Research Letter from Dr. Cosentino on cardiorenal outcomes with ertugliflozin by baseline metformin use, and this is a post hoc analysis of the VERTIS CV trial. Dr. Greg Hundley:           Oh, very good, Carolyn. Well, I've got an exchange of letters from Professors Boriani and Steinberg regarding the article “Driving Restrictions and Early Arrhythmias in Patients Receiving a Secondary Prevention Implantable Cardioverter-Defibrillator, the DREAM-ICD-II Study.” There's also an ECG Challenge from Professor Gao entitled “Syncope in a 3-Year-Old Child During the Perioperative Period. What is the diagnosis? What Signs Point Toward Impending Life-threatening Event?” Then, finally, there's a nice, On My Mind piece from Professor Greenland entitled “Insurance Payers Should Cover Selective Coronary Artery Calcium Testing in Intermediate Risk Primary Prevention Patients.” Well, Carolyn, how about we get on to that feature discussion and dive into the world of rejection after heart transplantation? Dr. Carolyn Lam:             Yay. Here we go. Dr. Greg Hundley:           Welcome, listeners, to this feature discussion on August 23rd. We have a very interesting article today to discuss with our author and associate editor pertaining to preclinical science and cardiac transplant rejection. Our author today is Dr. Kory Lavine from Washington University in St. Louis and our associate editor today is Dr. Thomas Eschenhagen from Hamburg, Germany. Welcome gentlemen. Kory, we'll start with you. Can you describe for us some of the background information pertaining to the construct of your study and what was the hypothesis that you wanted to address? Dr. Kory Lavine:               Well, thank you for having me. Our study focused on heart transplant rejection, which remains a major clinical challenge that limits both the survival of heart transplant recipients as well as availability of donor hearts. Current clinical practice really focuses on suppressing the immune system in a global way, and that is somewhat effective, but carries important risks that include infection and life-threatening malignancies. Many studies have appropriately focused on immune cells that infiltrate the transplanted heart that come from the recipient to search for new ways to suppress the immune system safely. What we've understood and learned over the past several years is that the donor heart has its own immune system and its own immune cells, and the majority of those immune cells that come with the donor heart are macrophages that can be broadly divided into two distinct lineages with different functions, tissue-resident macrophages, which lack the cell surface receptors CCR2, and monocyte-derived macrophages with expressed cell surface receptors CCR2. We tested the hypothesis in this study that these macrophages that come with the donor heart remain active for a period of time after transplantation and play important roles in either suppressing or accelerating heart transplant rejection. Dr. Greg Hundley:           What was the hypothesis that you wanted to address with your study? Dr. Kory Lavine:               Yeah, so our prior work and others' work within this field had suggested that tissue-resident macrophages, CCR2-negative macrophages, are inflammatory, and CCR2-positive macrophages have the opposite functions being inflammatory and play roles in potentiating and initiating inflammation in the heart. In this study, we hypothesized that CCR2-negative macrophages would protect from rejection, while CCR2-positive macrophages may promote heart transplant rejection and could serve as a new therapeutic target to prevent rejection in transplant recipients. Dr. Greg Hundley:           Excellent. Kory, can you describe for us the study design that you used to test your hypothesis? Dr. Kory Lavine:               Yeah. The study design and approach we used involved a mouse model of heart transplantation where we transplant a donor heart into a recipient mouse that's fully mismatched at all the MHC loci, and this serves as a nice model for both cellular and antibody-mediated rejection. To facilitate tracking these donor macrophages, we used various genetic lineage tracing systems and, to study their phenotypes, we used single-cell RNA sequencing and, to understand their function, we used mouse models that allow us to specifically deplete each of the donor macrophage populations as well as genetic models to manipulate their activation and signaling. Dr. Greg Hundley:           The outcome measures were going to be what? Dr. Kory Lavine:               Yeah. The outcome measures for transplant rejection in this mouse model are allograph survival, so the survival of the transplanted heart. We're able to directly look at how much rejection is present by histopathology, and then we're able to observe various mechanistic features using detailed phenotyping such as single-cell RNA sequencing and T-cell activation assays. Dr. Greg Hundley:           Very nice, Kory. Well, all, our listeners, we're very excited to hear what were your study results? Dr. Kory Lavine:               We learned that donor macrophages are dynamic and they survive for a period of time after transplantation or eventually lost due to transplant rejection. When we phenotyped the macrophages that came from the donor heart, we learned that they remained transcriptionally distinct from immune cells that enter the heart that were derived from the recipients, and they had important and distinct functions. If we depleted the tissue-resident macrophages that were CCR2-negative, we observed reduced allograph survival and increased rejection. If we depleted CCR2-positive macrophages that came from the donor heart, we observed improved allograph survival and reduced rejection. Mechanistically, we learned that CCR2-positive macrophages are activated through a MyD88-dependent pathway and, if we inhibited MyD88 cytokines which controls the expression of pro-inflammatory cytokines and chemokines, we could prolong the survival of the donor heart for a very significant period of time, reduce rejection and prevent the development of T-cells that would attack the donor heart. From a mechanistic aspect, what we uncovered is that this signaling pathway in CCR2-positive macrophages regulated the recruitment of an activation of antigen-presenting cells which played important roles in generating T-cells that would target the transplanted heart. Dr. Greg Hundley:           It sounds like a really informative and leap forward in the whole sphere of transplant rejection. Well, listeners, now we're going to turn to our associate editor, Dr. Thomas Eschenhagen. Thomas, you have many papers come across your desk. What attracted you to this particular paper and then, secondly, how do you put the results of this study really in the context of other research examining heart transplant rejection? Dr. Thomas Eschenhagen:           Yeah, thanks for having me. I mean, first, we got attracted by this paper because it's somewhat an out-of-the-box approach. It's not the standard approach to improve the systemic immunosuppression as many studies did and with actually a lot of success over the last 30 years, survivor got much better. There had been a lot of progress in the field of transplantation medicine as we all know, but as Kory said already, we still have 30% rejection, and these immunosuppressions come at a price. Having this study which turns around somehow the argumentation and looks at the donor organ was something which really attracted us. It uses advanced methods and it applies somewhat in a practical way a concept which emerged over the last, I don't know, maybe decade this concept that macrophages are really very different kind of cells. They're all called macrophages, but they're quite different and even maybe in certain respects having opposing effect. I think many people know about this M1/M2 concept. It's CCR2 receptor positive and negative. It's criticized by some people, but here we see that it really seems to be really important and, of course, then the third argument why we really like the story is that it has a specific, clear translation impact. I mean, looking at the heart, the donor heart, and potentially even treating the donor heart before transplanting it is something which comes immediately out of the story, and that's something which we found super attractive. Dr. Greg Hundley:           Really interesting, so really understanding the mechanism and focusing on donor hearts. Well, listeners, let's circle back with Kory. Kory, given that, what do you think is the next study that really needs to be performed in this sphere of research? Dr. Kory Lavine:               I think Thomas said it exactly as we're thinking about it, so the next area that we're really excited to attack and we're hopeful that the field will focus on is ways to build methods and technologies to treat the donor heart between the time of procurement and the time of transplant, when it's being transported and potentially even being perfused for a period of time. We're really interested in finding approaches to identify small molecules and other potential biologic therapies that could be used to prevent the activation of donor CCR2-positive macrophages. It's a really attractive approach because treating the donor heart ex vivo decreases the risk of adversely affecting other organs that may be transplanted if you're treating the donor, for instance, and it may decrease the risk of immunosuppression and infection by not having to treat the recipient and we're catching the heart in this window where the risks are much lower. The other area that we're really excited to focus on is trying to identify the exact mediators that are generated from donor CCR2-positive macrophages that mediate the recruitment and activation of antigen-presenting cells because that would represent another potential therapeutic target. Dr. Greg Hundley:           Very nice. Thomas, what are your thoughts about what might be the next study to be performed really in this sphere of research? Dr. Thomas Eschenhagen: It's obviously something rather a question to Kory than to me, but I agree to what he said. I think it is pretty obvious what are the next steps mechanistically on the one hand, but practically on the other hand. I mean, at this point, we are at the mouse level, so the question is to which extent can this concept be translated into larger animals and then finally in humans? I was wondering, given these newer methods to keep donor hearts alive for long, extended periods, I was wondering which extent you are already collaborating with the respective groups who develop this approach because that obviously would increase the window of opportunity here for drugs. I think it's really an exciting and pretty visible next steps which we see here, and I can just hope that you're going this path and that it will be successful. Dr. Greg Hundley:           Kory, any thoughts on those collaborations that Thomas just spoke of? Dr. Kory Lavine:               We're definitely establishing collaborations to focus on ex vivo profusion of donor hearts because that's, as Thomas mentioned, is a perfect window to manipulate the immune populations that are within the donor heart. Those studies have to be team science, they have to be collaborative and they have to have a focus on large animals and then moving into clinic. We're definitely forming those collaborations and excited to work as a group. Dr. Greg Hundley:           Very nice. Well, listeners, what an exciting paper to discuss here as part of this feature discussion from the world of preclinical science. We want to thank Dr. Kory Lavine from Washington University in St. Louis, Missouri, and also our own associate editor, Dr. Thomas Eschenhagen from Hamburg Germany, for really bringing us this research study highlighting that distinct populations of donor and recipient macrophages coexist within the transplanted heart, and donor CCR2-positive macrophages are key mediators of allograph rejection and deletion of MyD88 signaling in donor macrophages is sufficient to suppress rejection and extend allograph survival. 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 is copyright of the American Heart association, 2022. The opinions expressed by the 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.

A new research paper was published in Oncotarget on August 3, 2022, entitled, “A novel mechanism of regulation of the oncogenic transcription factor GLI3 by toll-like receptor signaling.” The transcription factor GLI3 is a member of the GLI family and has been shown to be regulated by canonical hedgehog (HH) signaling through smoothened (SMO). Little is known about SMO-independent regulation of GLI3. “Hedgehog (HH) signaling is well known for its role in embryonic development, cancer and inflammation [1–4]. At the center of HH signaling are the 2 receptors patched (PTCH1) and smoothened (SMO) along with GLI transcription factors [5]. In the absence of HH ligand, PTCH1 inhibits SMO.” In this study, researchers (Stephan J. Matissek, Mona Karbalivand, Weiguo Han, Ava Boutilier, Estefania Yzar-Garcia, Laura L. Kehoe, Devin Storm Gardner, Adam Hage, Krista Fleck, Vicki Jeffers, Ricardo Rajsbaum, and Sherine F. Elsawa) from the University of New Hampshire and University of Texas Medical Branch identified toll-like receptor (TLR) signaling as a novel pathway regulating GLI3 expression. The researchers showed that GLI3 expression is induced by LPS/TLR4 in human monocyte cell lines and peripheral blood CD14+ cells. Further analysis identified TRIF, but not MyD88, signaling as the adapter used by TLR4 to regulate GLI3. Using pharmacological and genetic tools, they identified IRF3 as the transcription factor regulating GLI3 downstream of TRIF. “Furthermore, using additional TLR ligands that signal through TRIF such as the TLR4 ligand, MPLA and the TLR3 ligand, Poly(I:C), we confirm the role of TRIF-IRF3 in the regulation of GLI3.” They found that IRF3 directly binds to the GLI3 promoter region and this binding was increased upon stimulation of TRIF-IRF3 with Poly(I:C). Using Irf3−/− MEFs, the researchers found that Poly(I:C) stimulation no longer induced GLI3 expression. Finally, using macrophages from mice lacking Gli3 expression in myeloid cells (M-Gli3−/−), they found that in the absence of Gli3, LPS stimulated macrophages secrete less CCL2 and TNF-α compared with macrophages from wild-type (WT) mice. “Taken together, these results identify a novel TLR-TRIF-IRF3 pathway that regulates the expression of GLI3 that regulates inflammatory cytokines and expands our understanding of the non-canonical signaling pathways involved in the regulation of GLI transcription factors.” DOI: https://doi.org/10.18632/oncotarget.28261 Correspondence to: Sherine F. Elsawa – Email: sherine.elsawa@unh.edu Keywords: GLI3, inflammation, TLR About Oncotarget: Oncotarget (a primarily oncology-focused, peer-reviewed, open access journal) aims to maximize research impact through insightful peer-review; eliminate borders between specialties by linking different fields of oncology, cancer research and biomedical sciences; and foster application of basic and clinical science. To learn more about Oncotarget, visit Oncotarget.com and connect with us on social media: Twitter – https://twitter.com/Oncotarget Facebook – https://www.facebook.com/Oncotarget YouTube – www.youtube.com/c/OncotargetYouTube Instagram – https://www.instagram.com/oncotargetjrnl/ LinkedIn – https://www.linkedin.com/company/oncotarget/ Pinterest – https://www.pinterest.com/oncotarget/ LabTube – https://www.labtube.tv/channel/MTY5OA SoundCloud – https://soundcloud.com/oncotarget For media inquiries, please contact: media@impactjournals.com. Oncotarget Journal Office 6666 East Quaker Str., Suite 1A Orchard Park, NY 14127 Phone: 1-800-922-0957 (option 2)

Research shows healthy home cooking equals a healthy mind   Edith Cowan University (Australia), March 21, 2022   Research from Edith Cowan University (ECU) has found being confident in the kitchen is not only good for your taste buds: it's also good for your mental health. In total, 657 participants undertook the seven-week healthy cooking course. At the same time, ECU Institute for Nutrition Research academics measured the program's effect on participants' cooking confidence and self-perceived mental health, as well as their overall satisfaction around cooking and diet-related behaviors. Researchers found those who participated in the program saw significant improvements in general health, mental health and subjective vitality immediately after the program which remained six months after completing the course, when compared to the study's control group. Improvements in cooking confidence, the ability to easily change eating habits and overcome lifestyle barriers to healthy eating were also reported. Also, the mental health benefits were equal among participants who were overweight or obese, and those in a healthy weight range.   (NEXT)   Resveratrol can help to reduce inflammation, study finds   Georgia State University September 28, 2021    A component of red wine and grapes can help control inflammation induced by a bacterial pathogen that is linked to upper respiratory tract inflammatory diseases such as asthma, chronic obstructive pulmonary diseases (COPD) and middle ear infection (otitis media), according to a study by researchers at Georgia State University. The findings, published in the online journal Scientific Reports, identify a novel mechanism that resveratrol, a compound found naturally in some plant foods such as grapes, uses to alleviate inflammation in airway disease. The results suggest this compound could offer health benefits and be used to develop new, effective anti-inflammatory therapeutic agents. This study found for the first time that resveratrol decreases NTHi-induced expression of pro-inflammatory mediators in airway epithelial cells and in the lungs of mice by enhancing MyD88 short, a negative regulator of inflammatory signaling pathways. MyD88 short is considered a "brake pedal protein" because it can tightly control inflammation induced by this respiratory pathogen. It could be a critical target with significant therapeutic potential for suppressing inflammation associated with chronic airway disease.   (NEXT)    Psoriasis Linked to Low Vitamin E Levels   Dalian Medical College (China), March 21, 2022   Struggling with psoriasis? If so, you might need to increase your vitamin E intake. A meta-analysis published in December 2021 links this condition, along with other dermatologic grievances including acne and vitiligo, to low serum levels of vitamin E. Vitamin E has long been known to be essential for biochemical processes that are linked to psoriasis, including its involvement in immune system function, fatty acid metabolism and free-radical regulation. The results from this new analysis showed that the average person with psoriasis had 2.7-fold lower serum vitamin E levels compared to the average person in the controls, which was a stronger relationship than any of the skin disorders included.   (NEXT)   The secret to staying young: New research highlights power of life long exercise to keep muscles healthy   University of Copenhagen, March 21, 2022   Lifelong physical activity could protect against age-related loss of muscle mass and function, according to research published in The Journal of Physiology. Individuals aged 68 and above who were physically active throughout their life have healthier ageing muscle that has superior function and is more resistant to fatigue compared to inactive individuals, both young and old. This is the first study to investigate muscle, stem cell and nerve activity in humans. The researchers from University of Copenhagen, Denmark, found that elderly individuals who keep physically active throughout their adult life, whether by taking part in resistance exercise, ball games, racket sports, swimming, cycling, running and/or rowing had a greater number of muscle stem cells, otherwise known as satellite cells in their muscle. These cells are important for muscle regeneration and long-term growth and protect against nerve decay.   (NEXT)   Could a shot of orange juice boost brain power for men?   University of Reading (UK), September 23, 2021   Data published in the European Journal of Nutrition indicated that a 240 ml glass of the flavonoid-rich orange juice was associated with significantly improved scores for attention, executive function, and psychomotor speed in healthy middle-aged men without mild cognitive impairment six hours after consumption, compared with placebo. The researchers recruited 24 healthy men aged between 30 and 65 to participate in their randomized, double-blind, crossover study. The men were randomly assigned to consumer orange juice containing 272 mg of flavonoid or a calorie-matched placebo, with the interventions separated by two weeks. A battery of tests revealed that, compared to placebo, the flavonoid-rich orange juice was associated with significantly better performance on tests of executive function and psychomotor speed. Alertness was also reportedly improved following orange juice consumption.  

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.04.236968v1?rss=1 Authors: Plasil, S. L., Seth, A., Homanics, G. E. Abstract: The development of CRISPR/Cas9 technology has vastly sped up the process of genome editing by introducing a bacterial system that can be exploited for reverse genetics-based research. However, generating homozygous knockout (KO) animals using traditional CRISPR/Cas9-mediated techniques requires three generations of animals. A founder animal with a desired mutation is crossed to produce heterozygous F1 offspring which are subsequently interbred to generate homozygous F2 KO animals. This study describes a novel adaptation of the CRISPR/Cas9-mediated method to develop a homozygous gene-targeted KO animal cohort in one generation. A well-characterized ethanol-responsive gene, MyD88, was chosen as a candidate gene for generation of MyD88-/- mice as proof of concept. Previous studies have reported changes in ethanol-related behavioral outcomes in MyD88 KO mice. Therefore, it was hypothesized that a successful one-generation KO of MyD88 should reproduce decreased responses to ethanols sedative effects, as well as increased ethanol consumption in males that were observed in previous studies. One-cell mouse embryos were simultaneously electroporated with four gRNAs targeting a critical Exon of MyD88 along with Cas9. DNA and RNA analysis of founder mice revealed a complex mix of genetic alterations, all of which were predicted to ablate MyD88 gene function. This study additionally compared responses of Mock treatment control mice generated through electroporation to controls purchased from a vendor. No substantial behavioral changes were noted between control cohorts. Overall, the CRISPR/Cas9 KO protocol reported here, which we call CRISPR Turbo Accelerated KnockOut (CRISPy TAKO), will be useful for reverse genetic in vivo screens of gene function in whole animals. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.04.30.068924v1?rss=1 Authors: Smith, C. J., Kingsbury, M. A., Dziabis, J. E., Hanamsagar, R., Malacon, K. E., Tran, J. N., Norris, H. A., Gulino, M., Bilbo, S. D. Abstract: Decreases in social behavior are a hallmark aspect of acute sickness behavior in response to infection. However, immune insults that occur during the perinatal period may have long-lasting consequences for adult social behavior by impacting the developmental organization of underlying neural circuits. Microglia, the resident immune cells of the central nervous system, are sensitive to immune stimulation and play a critical role in the developmental sculpting of neural circuits, making them likely mediators of this process. Here, we investigated the impact of a postnatal day (PND) 4 lipopolysaccharide (LPS) challenge on social behavior in adult mice. Somewhat surprisingly, neonatal LPS treatment decreased sociability in adult female, but not male mice. LPS-treated females also displayed reduced social interaction and social memory in a social discrimination task as compared to saline-treated females. Somatostatin (SST) interneurons within the anterior cingulate cortex (ACC) have recently been suggested to modulate a variety of social behaviors. Interestingly, the female-specific changes in social behavior observed here were accompanied by an increase in SST interneuron number in the ACC. Finally, these changes in social behavior and SST cell number do not appear to depend on microglial inflammatory signaling, because microglia-specific genetic knock-down of myeloid differentiation response protein 88 (MyD88; the removal of which prevents LPS from increasing proinflammatory cytokines such as TNF alpha; and IL-1 beta) did not prevent these LPS-induced changes. This study provides novel evidence for enduring effects of neonatal immune activation on social behavior and SST interneurons in females, independent of microglial inflammatory signaling. Copy rights belong to original authors. Visit the link for more info

In dieser Studie wurde die Kompetenz des Immunsystems von Turopolje (TxT), Deutsche Landrasse x Pietrain (LxP) und Deutsche Landrasse x Turopolje (LxT) verglichen. Die verschiedenen Rassen sind Vertreter einer alten und einer modernen Rasse und einer Kreuzung von beiden. Hauptziel war es zu untersuchen, ob sich die verschiedenen Rassen in ihrer Immunabwehr gegenüber einer Infektion unterscheiden und wie das Immunsystem durch Stressoren belastet wird. Außerdem wurde untersucht, ob sich LxT zur kommerziellen Mast eignet. Unterschiede in der Sekretion von Immunglobulin G und M im Kolostrum und reifen Milch der Deutsche Landrasse und Turopolje Sauen, sowie deren Aufnahme durch die Ferkel wurde mittels ELISA untersucht. Nach dem Absetzen der Ferkel wurden zwei getrennte Gruppen gebildet: Die erste Gruppe wurde mit einem attenuierten Lebendimpfstoff gegen das Porzine Reproduktive und Respiratorische Syndrom Virus (PRRS MLV) immunisiert, um eine Infektion zu simulieren. Die Fragmente des PRRS MLV wurden aus dem Serum, den Leukozyten, den Tonsillen und dem Lymphonodus tracheobronchale extrahiert und mittels qRT-PCR gemessen. Durch ELISA wurden die Konzentrationen der Interleukine-1β, 6, 10 und 12 gemessen. Die Genexpression von CD163, SIGLEC1, Mx1, TLR7 und TLR8, TRAF6, Myd88, Interleukin 1, 6, 8, 10, 12, TNFα, TGFβ und CXCL12 wurde näher untersucht. Innerhalb der nicht geimpften Gruppe untersuchte man den Einfluss von Stress auf das Immunsystem. Hierbei wurde die Konzentration von Interleukin 6, 10, 12 im Plasma mittels ELISA, die Genexpression in den Lymphozyten durch qRT-PCR von Interleukin 1β, 6, 10, 12 und TNFα bestimmt. Außerdem wurde eine mitogenstimulierte Lymphozytenproliferation mittels Lumineszenzmessung durchgeführt. Bei beiden Gruppen wurde ein Differentialblutbild angefertigt, um Veränderungen im weißen Blutbild untersuchen zu können. Weiterhin wurde mittels ELISA die Immunglobulinkonzentration G und M im Serum untersucht. Es wurde in der Gruppe der immunisierten Tiere sichtbar, dass die Rassen unterschiedlich auf die Vakzination reagierten. TxT zeigt keine Konzentrationsveränderung von Interleukin 1β im Plasma. Durch die unveränderte Konzentration des Interleukins könnten vermehrt zytotoxische T Zellen gebildet werden. Als Folge wird TNFα aufreguliert. TNFα inhibiert CD163, daher wird nur eine geringe Anzahl von B-Zellen aktiviert und es werden spezifische Antikörper gebildet. Im Gegensatz dazu reagieren die beiden anderen Rassen mit einer Immunantwort des Typs 2. Die oben beschriebene Inhibierung kann nicht stattfinden und es kommt zur Synthese der B-Zellen und zu einer erhöhten Konzentration an Immunglobulinen und spezifischen Antikörpern. Die Ergebnisse meiner Studie können tendenziell den Einfluss des Stresses auf das Immunsystem bestätigen. So deuten bei TxT die geringere Immunglobulinkonzentration und das Differentialblutbild darauf hin, dass die Immunreaktion auf Stress eher auf T-Zellen basiert (Immunreaktion Typ 1). Auch bei LxT und LxP scheint es, dass die Immunantwort Typ2 und eine Hochregulation der Genexpression von IL6 und die Konzentration im Plasma dominieren. Weiterhin besteht eine Tendenz, dass TxT auf Stress robuster reagieren als die beiden anderen Rassen. Nach der Schlachtung wurden die Schweinehälften aller Rassen und Gruppen mittels der SEUROP-Klassifizierung eingeteilt und bewertet. Bei Schweinen, die in der 25. Lebenswoche geschlachtet wurden, untersuchte man zusätzlich den Tropfsaftverlust und das intramuskuläre Fett. Im Vergleich der Schachtkörper und Fleischqualität schnitten die Tiere der Kreuzungsrasse (LxT) qualitativ am besten ab. Schlussfolgernd ist die Kreuzungsrasse (LxT) zur Mästung als Nutzungsrasse geeignet. Sie stellt eine Bereicherung innerhalb der kommerziellen Schweinefleischproduktion dar.

Die Ischämie-Reperfusion in der Niere führt zur Aktivierung des angeborenen Immunsystems mit nachfolgender steriler Entzündungsreaktion und Gewebeschädigung der Niere, das v.a. das Tubulussystem betrifft. Es werden v.a. residente dendritische Zellen aktiviert, die die größte Immunzellpopulation in der Niere darstellen.In der weiteren Signaltransduktion sind v.a. TLR2 und TLR4 involviert, die über MyD88 proinflammatorischen Zytokinen/Chemokinen induzieren. Die proinflammatorische Wirkung wird dabei u.a. über IRF5 bewirkt, das an MyD88 andockt. Diese Funktion wird von IRF4 gehemmt, das als kompetitiver Faktor IRF5 von seiner Bindungsstelle verdrängt. Die negativ regulatorische Wirkung von IRF4 schützt die Niere vor zu starker Entzündung und dadurch vor zu starker Gewebeschädigung. Dadurch wird das Ausmaß des aktuen Nierenversagens reduziert. IRF4 wird durch Sauerstoffradikale im Rahmen der Ischämie-Reperfusion induziert. Nach der Gewebeschädigung und Induktion einer Entzündung wird IRF4 erst verzögert exprimiert, um die Entzündung wieder zu begrenzen.

Two related ligands that activate the same receptor have different effects on immune system stimulation and inflammation.

Introduction. Physical inactivity and obesity are independent risk factors for atherosclerosis. We analyzed the immunomodulatory capacity of 10-week intensified exercise training (ET) in obese and lean athletes. Markers of the innate immune response were investigated in obese (ONE: ET

Innate immune activation via IL-1R or Toll-like receptors (TLR) contibutes to acute kidney injury but its role in tissue remodeling during chronic kidney disease is unclear. SIGIRR is an inhibitor of TLR-induced cytokine and chemokine expression in intrarenal immune cells, therefore, we hypothesized that Sigirr-deficiency would aggravate postobstructive renal fibrosis. The expression of TLRs as well as endogenous TLR agonists increased within six days after UUO in obstructed compared to unobstructed kidneys while SIGIRR itself was downregulated by day 10. However, lack of SIGIRR did not affect the intrarenal mRNA expression of proinflammatory and profibrotic mediators as well as the numbers of intrarenal macrophages and T cells or morphometric markers of tubular atrophy and interstitial fibrosis. Because SIGIRR is known to block TLR/IL-1R signaling at the level of the intracellular adaptor molecule MyD88 UUO experiments were also performed in mice deficient for either MyD88, TLR2 or TLR9. After UUO there was no significant change of tubular interstitial damage and interstitial fibrosis in neither of these mice compared to wildtype counterparts. Additional in-vitro studies with CD90+ renal fibroblasts revealed that TLR agonists induce the expression of IL-6 and MCP-1/CCL2 but not of TGF-β, collagen-1α or smooth muscle actin. Together, postobstructive renal interstitial fibrosis and tubular atrophy develop independent of SIGIRR, TLR2, TLR9, and MyD88. These data argue against a significant role of these molecules in renal fibrosis.

Chitin, after cellulose the second most abundant polysaccharide in nature, is an essential component of exoskeletons of crabs, shrimps and insects and protects these organisms from harsh conditions in their environment. Unexpectedly, chitin has been found to activate innate immune cells and to elicit murine airway inflammation. The skin represents the outer barrier of the human host defense and is in frequent contact with chitin-bearing organisms, such as house-dust mites or flies. The effects of chitin on keratinocytes, however, are poorly understood. We hypothesized that chitin stimulates keratinocytes and thereby modulates the innate immune response of the skin. Here we show that chitin is bioactive on primary and immortalized keratinocytes by triggering production of pro-inflammatory cytokines and chemokines. Chitin stimulation further induced the expression of the Toll-like receptor (TLR) TLR4 on keratinocytes at mRNA and protein level. Chitin-induced effects were mainly abrogated when TLR2 was blocked, suggesting that TLR2 senses chitin on keratinocytes. We speculate that chitin-bearing organisms modulate the innate immune response towards pathogens by upregulating secretion of cytokines and chemokines and expression of MyD88-associated TLRs, two major components of innate immunity. The clinical relevance of this mechanism remains to be defined.

Toll-like receptors (TLRs) are in the front-line during the initiation of an innate immune response against invading pathogens. TLRs are type I transmembrane proteins that are expressed on the surface of immune system cells. They are evolutionarily conserved between insects and vertebrates. To date, 13 groups of mammalian TLRs have been identified, ten in humans and 13 in mice. They share a modular structure that consists of a leucine-rich repeat (LRR) ectodomain, a single transmembrane helix and a cytoplasmic Toll/interleukin-1 receptor (TIR) domain. Most TLRs have been shown to recognize pathogen-associated molecular patterns (PAMPs) from a wide range of invading agents and initiate intracellular signal transduction pathways to trigger expression of genes, the products of which can control innate immune responses. The TLR signaling pathways, however, must be under tight negative regulation to maintain immune balance because over-activation of immune responses in the body can cause autoimmune diseases. The TLR ectodomains are highly variable and are directly involved in ligand recognition. So far, crystal structures are missing for most TLR ectodomains because structure determination by X-ray diffraction or nuclear magnetic resonance (NMR) spectroscopy experiments remains time-consuming, and sometimes the crystallization of a protein can be very difficult. Computational modeling enables initial predictions of three-dimensional structures for the investigation of receptor-ligand interaction mechanisms. Computational methods are also helpful to develop new TLR agonists and antagonists that have therapeutic significance for diseases. In this dissertation, an LRR template assembly approach for homology modeling of TLR ligand-binding domains is discussed. To facilitate the modeling work, two databases, TollML and LRRML, have been established. With this LRR template assembly approach, the ligand-binding domains of human TLR5-10 and mouse TLR11-13 were modeled. Based on the models of human TLR7, 8 and 9, we predicted potential ligand-binding residues and possible configurations of the receptor-ligand complex using a combined procedure. In addition, we modeled the cytoplasmic TIR domains of TLR4 and 7, the TLR adaptor protein MyD88 (myeloid differentiation primary response protein 88) and the TLR inhibitor SIGIRR (Single immunoglobulin interleukin-1 receptor-related molecule) to investigate the structural mechanism of TLR negative regulation.

Mit der vorliegenden Arbeit soll der Stellenwert des unspezifischen angeborenen Immunsystems im Rahmen der chronischen Transplantatabstoßung nach allogener orthotoper Herztransplantation näher dargestellt werden. Humane Toll-like Rezeptoren initiieren Signalübertragungswege beispielsweise über ihr Signaladaptermolekül MyD88 und induzieren damit die Translokation von NF-kB in den Zellkern. Dies startet in antigenpräsentierenden Zellen einen Reifungsprozess, welcher in Expression von kostimulatorischen Molekülen wie B7-1 und Freisetzung von pro-inflammatorischen Zytokinen wie IL-12 und TNF-a mündet. Dieses pro-inflammatorische Milieu kann zur Aktivierung der erworbenen Immunantwort mit Aktivierung und Differenzierung naiver T-Zellen zu TH1-Lymphozyten führen. Als ersten Hinweis einer möglichen Beteiligung des Toll-Rezeptorsystems an der Aktivierung von Effektorfunktionen des angeborenen Immunsystems haben wir die Regulation von hTLR2 und hTLR4 sowie die daraus resultierende Expression von B7-1 auf peripher zirkulierenden CD14+ Monozyten in Patienten nach Herztransplantation untersucht. Im Vergleich zu Patienten 1-3 Jahre nach Herztransplantation ohne Endotheldysfunktion, als frühes klinisch detektierbares Zeichen einer beginnenden Transplantatvaskulopathie, weisen zirkulierende Monozyten von Transplantatempfängern mit Endotheldysfunktion eine erhöhte Expression von hTLR2 und hTLR4 auf. Auch das kostimulatorische B7-1 Molekül und die nachgeschalteten freigesetzten Zytokine IL-12 und TNF-a sind bei der Patientengruppe mit endothelialer Dysfunktion signifikant erhöht.

Nesta edição do podcast, apresento-vos o artigo submetido por Schubert et al. Nature Immunology. 2008, volume 9: 558, do Institute for Molecular Medicine and Experimental Immunology, Friedrich Wilhelms University, Bona, Alemanha. Este artigo demonstra como o processo de apresentação cruzada decorre em células dendriticas. A apresentação cruzada, do inglês "cross-presentation", é o processo de apresentação de antigénios extracelulares via moléculas de MHC classe I. Os autores demonstram num modelo onde células dendriticas pulsadas são ovalbumina, que o antigénio é capturada pelos receptores de manose em vesiculas de endocitose primárias. Ovalbumina é também colocalizada neste endosomas primários com o complexo TAP (Transporter Associated with antigen Processing). A estimulação de clones T CD8 especificos do peptideo SIINFEKL é dependente da acção do proteasoma, e dependente da fusão dos endosomas primários com a membrana celular. O segundo facto de relevância demonstrado pelos autores é a necessidade de um processo inflamatório (endotoxinas) crucial para a ocorrência da apresentação cruzada, nomeadamente devido a necessidade de TLR4, um receptor TOLL-LIKE-RECEPTOR e o mediador de signalização MyD88 serem necessários ao processo. Estas evidências, parecem sugerir que provavelmente o processo de apresentação cruzada poderá ocorrer somente em presença de elevadas quantidades de antigénio e processos inflamatórios onde LPS esteja envolvido em grandes quantidades. Algo de raro ... Até breve!

Nesta edição apresento-vos um artigo muito elegante (Kool et al 2008 JEM; 205: 869 e bem desenhado onde se demonstra os efeitos do agente adjuvante na vacinação com o antigénio OVALBUMINA. O trabalho mostra-nos a dinâmica das respostas T CD4 especificas do antigénio e sobretudo como o processo esta dependente da mobilização de células do sistema imunológico inato, nomeadamente monocitos que após entrarem em contacto com o ambiente inflamatório criado pelo adjuvante se diferenciam em células dendriticas maturas que migram para os nódulos linfáticos drenantes e não-drenantes activando ai as células T CD4 naive em circulação. Os autores deste trabalho também demonstram que a acção do adjuvante (hidróxido de alumínio) é dependente da produção de acido úrico (lembram-se dele) e da mediação via MyD88, um elemento chave na sinalização intracelular dos receptores Toll-like. Uma boa leitura para este mês de calor... Pedro