Podcasts about tlr7

REDIFFUSIONLe fait a encore une fois été remarqué pendant la récente épidémie de Coronavirus. En réanimation, les lits d'hôpital étaient occupés plus fréquemment par des patients masculins que féminins. Sur le tableau des décès des suites du Covid-19, la proportion d'hommes atteint 57,8% en France contre 42,2% de femmes, une tendance confirmée dans tous les pays relevés, sauf le Vietnam et la Corée du Sud.Les femmes résistent mieux aux infections que les hommes, et ce point a été à nouveau confirmé par une étude récente, qui ajoute que l'âge n'influence pas ce constat. Une femme de 80 ans sera toujours mieux armée face aux virus qu'un homme du même âge.L'influence des interférons de type 1Grippe, VIH, SARS-Cov2 : qu'ont en commun ces infections ? D'après les statistiques médicales obtenues sur les dernières décennies, les femmes résistent mieux à ces virus que les hommes. Le mécanisme impliqué dans cette différence est connu depuis longtemps, et se base sur une composante génétique.Il faut d'abord savoir qu'en cas d'infection par un virus de type grippe ou Covid-19, certaines cellules du corps détectent la présence de l'indésirable grâce à un récepteur nommé TLR7. Ces cellules relarguent alors dans le sang des molécules antivirales, les cyotkines, dont l'une porte le nom d'interféron de type 1. Puissants et aptes à stopper la réplication du virus, les interférons ont un rôle crucial dans la lutte contre l'infection. Il s'avère que les femmes produisent généralement davantage d'interférons que les hommes lors de la stimulation du récepteur TRL7, pour une bonne raison : le gène qui code ce récepteur est situé sur le chromosome X, que les femmes possèdent en double exemplaire.Les études qui avaient été menées jusqu'à récemment portaient surtout sur des femmes de moins de 60 ans. Mais, en 2022, des chercheurs de l'Inserm, du CNRS et de l'université Toulouse 3 ont collaboré pour étudier la réponse immunitaire de l'organisme chez les femmes plus âgées... Hébergé par Acast. Visitez acast.com/privacy pour plus d'informations.

REDIFFUSION Le fait a encore une fois été remarqué pendant la récente épidémie de Coronavirus. En réanimation, les lits d'hôpital étaient occupés plus fréquemment par des patients masculins que féminins. Sur le tableau des décès des suites du Covid-19, la proportion d'hommes atteint 57,8% en France contre 42,2% de femmes, une tendance confirmée dans tous les pays relevés, sauf le Vietnam et la Corée du Sud. Les femmes résistent mieux aux infections que les hommes, et ce point a été à nouveau confirmé par une étude récente, qui ajoute que l'âge n'influence pas ce constat. Une femme de 80 ans sera toujours mieux armée face aux virus qu'un homme du même âge. L'influence des interférons de type 1 Grippe, VIH, SARS-Cov2 : qu'ont en commun ces infections ? D'après les statistiques médicales obtenues sur les dernières décennies, les femmes résistent mieux à ces virus que les hommes. Le mécanisme impliqué dans cette différence est connu depuis longtemps, et se base sur une composante génétique. Il faut d'abord savoir qu'en cas d'infection par un virus de type grippe ou Covid-19, certaines cellules du corps détectent la présence de l'indésirable grâce à un récepteur nommé TLR7. Ces cellules relarguent alors dans le sang des molécules antivirales, les cyotkines, dont l'une porte le nom d'interféron de type 1. Puissants et aptes à stopper la réplication du virus, les interférons ont un rôle crucial dans la lutte contre l'infection. Il s'avère que les femmes produisent généralement davantage d'interférons que les hommes lors de la stimulation du récepteur TRL7, pour une bonne raison : le gène qui code ce récepteur est situé sur le chromosome X, que les femmes possèdent en double exemplaire. Les études qui avaient été menées jusqu'à récemment portaient surtout sur des femmes de moins de 60 ans. Mais, en 2022, des chercheurs de l'Inserm, du CNRS et de l'université Toulouse 3 ont collaboré pour étudier la réponse immunitaire de l'organisme chez les femmes plus âgées... Learn more about your ad choices. Visit megaphone.fm/adchoices

References Mozart - Flute and Harp Concerto in C, K. 299 J Immunol Res. 2021; 2021: 8263829. J Immunol. 2022 Jan 1;208(1):155-168 Front. Immunol. 2022.31 March. Sec. Molecular Innate Immunity Volume 13 –202. Cells. 2022 Mar; 11(6): 997 Nature Immunology 2020. volume 21, pages1256–1266. Nature Immunology 2011. 12 (12) 10. --- Send in a voice message: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/message Support this podcast: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/support

References Rheumatology (Oxford). 2023 Jul; 62(7):2611–2620 Science Immunology.2018.26 Jan Vol 3, Issue 1. Nature. 2020 Jun; 582(7813): 577–581. --- Send in a voice message: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/message Support this podcast: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/support

References Nature. 2020 Jun; 582(7813): 577–581 Science Immunology 2018.26 Jan Vol 3, Issue 1 --- Send in a voice message: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/message Support this podcast: https://podcasters.spotify.com/pod/show/dr-daniel-j-guerra/support

This month on Episode 48 of Discover CircRes, host Cynthia St. Hilaire highlights three original research articles featured in the April 28th issue of Circulation Research. This Episode also includes a discussion between Dr Mina Chung, Dr DeLisa Fairweather and Dr Milka Koupenova, who all contributed to manuscripts to the May 12th Compendium on Covid-19 and the Cardiovascular System.     Article highlights:   Heijman, et al. Mechanisms of Enhanced SK-Channel Current in AF   Chen, et al. IL-37 Attenuates Platelet Activation   Enzan, et al. ZBP1 Protects Against Myocardial Inflammation   Compendium on Covid-19 and the Cardiovascular System.   Cindy St. Hilaire: Hi, and welcome to Discover CircRes, the podcast of the American Heart Association's journal, Circulation Research. I'm your host, Dr Cindy St. Hilaire, from the Vascular Medicine Institute at the University of Pittsburgh. Today, I'm going to be highlighting articles from our April 28th and May 12th issues of Circulation Research. I'm also going to have a chat with Dr Mina Chung, Dr DeLisa Fairweather and Dr Milka Koupenova, who all contributed to articles in the May 12th COVID Compendium. But before we have that interview, let's first talk about some highlights.   The first article I want to present is titled Enhanced Calcium-Dependent SK-Channel Gating and Membrane Trafficking in Human Atrial Fibrillation. This article is coming from the University of Essen by Heijman and Zhou, et al. Atrial fibrillation is one of the most common forms of heart arrhythmia in humans and is characterized by irregular, often rapid heartbeats that can cause palpitations, dizziness and extreme fatigue. Atrial fibrillation can increase a person's risk of heart failure, and though treatments exist such as beta blockers, blood thinners and antiarrhythmia medications, they can have limited efficacy and side effects. A new family of drugs in development are those blocking small-conductance calcium-activated potassium channels called SK channels, which exhibit increased activity in animal models of AF and suppression of which attenuates the arrhythmia. In humans however, the relationship between SK channels and atrial fibrillation is less clear, at least in terms of SK channel mRNA levels. Because mRNA might not reflect actual channel activity, this group looked at just that and they found indeed that channel activity was increased in cardiomyocytes from atrial fibrillation patients compared to those from controls even though the mRNA and protein levels themselves were similar. The altered currents were instead due to changes in SK channel trafficking and membrane targeting. By confirming that SK channels play a role in human atrial fibrillation, this work supports the pursuit of SK channel inhibitors as possible new atrial fibrillation treatments.   The next article I want to present is titled IL-37 Attenuates Platelet Activation and Thrombosis Through IL-1R8 Pathway. This article comes from Fudan University by Chen and Hong, et al. Thrombus formation followed by the rupture of a coronary plaque is a major pathophysiological step in the development of a myocardial infarction. Understanding the endogenous antithrombotic factors at play could provide insights and opportunities for developing treatments. With this in mind, Chen and Hong, et al. investigated the role of interleukin-1 receptor 8, or IL-1R8, which suppresses platelet aggregation in mice, and of IL-37, a newly discovered human interleukin that forms a complex with IL-1R8 and is found at increased levels in the blood of patients with myocardial infarction. Indeed, the amount of IL-37 in myocardial infarction patients negatively correlates with platelet aggregation. They also show that treatment of human platelets in vitro with IL-37 suppresses the cell's aggregation and does so in a concentration-dependent manner. Moreover, injection of the protein into the veins of mice inhibits thrombus development and better preserves heart function even after myocardial infarction. Such effects were not seen in mice lacking IL-1R8. This suggests IL-37's antithrombotic action depends on its interaction with the receptor. Together, the results suggest IL-37 could be developed as a antithrombotic agent for use in MI patients or indeed perhaps other thrombotic conditions.   The last article I want to present before our interview is titled ZBP1 Protects Against Mitochondrial DNA-Induced Myocardial Inflammation in Failing Hearts. This article is coming from Kyushu University and is by Enzan, et al. Myocardial inflammation is a key factor in the pathological progression of heart failure and occurs when damaged mitochondria within the stricken cardiomyocyte release their DNA, triggering an innate inflammatory reaction. In a variety of cells, DNA sensors such as Z-DNA-binding protein 1 or ZBP1 are responsible for such mitochondrial DNA-induced inflammation. In theory then, it's conceivable that therapeutic suppression of ZBP1 might reduce myocardial inflammation in heart failure and preserve function. But as Enzan and colleagues have now discovered to their surprise, mice lacking ZBP1 exhibited worse, not better heart inflammation and more failure after induced myocardial infarction. Indeed, the test animals' hearts had increased infiltration of immune cells, production of inflammatory cytokines and fibrosis together with decreased function compared with the hearts of mice with normal ZBP1 levels. Experiments in rodent cardiomyocytes further confirmed that loss of ZBP1 exacerbated mitochondrial DNA-induced inflammatory cytokine production while overexpression of ZBP1 had the opposite effect. While the reason behind ZBP1's opposing roles in different cells is not yet clear, the finding suggests that boosting ZBP1 activity in the heart might be a strategy for mitigating heart inflammation after infarction.   Cindy St. Hilaire:         The May 12th issue of Circulation Research is our COVID compendium, which consists of a series of 10 reviews on all angles of COVID-19 as it relates to cardiovascular health and disease. Today, three of the authors of the articles in this series are here with me. Dr Mina Chung is a professor of medicine at the Cleveland Clinic. She and Dr Tamanna Singh and their colleagues wrote the article, A Post Pandemic Enigma: The Cardiovascular Impact of Post-Acute Sequelae of SARS-CoV-2. Dr DeLisa Fairweather, professor of medicine, immunology and clinical and translational science at the Mayo Clinic, and she and her colleagues penned the article, COVID-19 Myocarditis and Pericarditis. Dr Milka Koupenova is an assistant professor of medicine at the UMass Chan School of Medical and she led the group writing the article, Platelets and SARS-CoV-2 During COVID-19: Immunity, Thrombosis, and Beyond. Thank you all for joining me today.   DeLisa Fairweather:    Thank you so much for having us.   Mina Chung:   Thank you.   Milka Koupenova:       Thank you for having us, Cindy.   Cindy St. Hilaire:         In addition to these three articles, we have another seven that are on all different aspects of COVID. Dr Messinger's group wrote the article, Interaction of COVID-19 With Common Cardiovascular Disorders. Emily Tsai covered cell-specific mechanisms in the heart of COVID-19 patients. Mark Chappell and colleagues wrote about the renin-angiotensin system and sex differences in COVID-19. Michael Bristow covered vaccination-associated myocarditis and myocardial injury. Jow Loacalzo and colleagues covered repurposing drugs for the treatment of COVID-19 and its cardiovascular manifestations. Dr Stephen Holby covered multimodality cardiac imaging in COVID, and Arun Sharma covered microfluidic organ chips in stem cell models in the fight against COVID-19.   Cindy St. Hilaire          As of today, worldwide, there have been over six hundred million individuals infected with the virus and more than six and a half million have died from COVID-19. In the US, we are about a sixth of all of those deaths. Obviously now we're in 2023, the numbers of individuals getting infected and dying are much, much lower. As my husband read to me this morning, one doctor in Boston was quoted saying, "People are still getting wicked sick." In 75% of deaths, people have had underlying conditions and cardiovascular disease is found in about 60% of all those deaths. In the introduction to the compendium, you mentioned that the remarkable COVID-19 rapid response initiative released by the AHA, which again is the parent organization of Circ Research and this podcast, if I were to guess when that rapid response initiative started, I would've guessed well into the pandemic, but it was actually March 26th, 2020. I know in Pittsburgh, our labs have barely shut down. So how soon after we knew of SARS-CoV-2 and COVID, how soon after that did we know that there were cardiovascular complications?   Mina Chung:               I think we saw cardiovascular complications happening pretty early. We saw troponin increases very early. It was really amazing what AHA did in terms of this rapid response grant mechanism. You mentioned that the RFA was announced, first of all, putting it together by March 26th when we were just shutting down in March was pretty incredible to get even the RFA out. Then the grants were supposed to be submitted by April 6th and there were 750 grants that were put together and submitted. They were all reviewed within 10 days from 150 volunteer reviewers. The notices were distributed April 23rd, less than a month out.   Cindy St. Hilaire:         Amazing.   Mina Chung:               So this is an amazing, you're right, paradigm for grant requests and submissions and reviews.   DeLisa Fairweather:    For myocarditis, reports of that occurred almost immediately coming out of China, so it was incredibly rapid.   Cindy St. Hilaire:         Yeah, and that was a perfect lead up to my next question. Was myocarditis, I guess, the first link or the first clue that this was not just going to be a respiratory infection?   DeLisa Fairweather:    I think myocarditis appearing very early, especially it has a history both of being induced by viruses, but being strongly an autoimmune disease, the combination of both of those, I think, started to hint that something different was going to happen, although a lot of people probably didn't realize the significance of that right away.   Cindy St. Hilaire:         What other disease states, I guess I'm thinking viruses, but anything, what causes myocarditis and pericarditis normally and how unique is it that we are seeing this as a sequelae of COVID?   DeLisa Fairweather:    I think it's not surprising that we find it. Viruses around the world are the primary cause of myocarditis, although in South America, it's the parasite Trypanosoma cruzi. Really, many viruses that also we think target mitochondria, including SARS-CoV-2, have an important role in driving myocarditis. Also, we know that SARS-CoV-1 and MERS also reported myocarditis in those previous infections. We knew about it beforehand that they could cause myocarditis.   Cindy St. Hilaire:        Is it presenting differently in a COVID patient than say those South American patients with the... I forget the name of the organism you said, but does it come quickly or get worse quickly or is it all once you get it, it's the same progression?   DeLisa Fairweather:    Yeah. That's a good question. Basically, what we find is that no matter what the viral infection is, that myocarditis really appears for signs and symptoms and how we treat it identically and we see that with COVID-19. So that really isn't any different.   Cindy St. Hilaire:         Another huge observation that we noticed in COVID-19 patients, which was the increased risk of thrombic outcomes in the patients. Dr Koupenova, Milka, you are a world expert in platelets and viruses and so you and your team were leading the writing of that article. My guess is knowing what you know about platelets and viruses, this wasn't so surprising to you, but could you at least tell us the state of the field in terms of what we knew about viruses and platelets before COVID, before Feb 2020?   Milka Koupenova:       Before Feb 2020, we actually knew that influenza gets inside in platelets. It leads to not directly prothrombotic events, but it would lead to release of complement 3 from them. That complement 3 would actually increase the immunothrombosis by pushing neutrophils to release their DNA, forming aggregates. In cases when you have compromised endothelium and people with underlying conditions, you would expect certain thrombotic outcomes. That, we actually published 2019 and then 2020 hit. The difference between influenza and SARS-CoV-2, they're different viruses. They carry their genome in a different RNA strand. I remember thinking perhaps viruses are getting inside in platelets, but perhaps they do not. So we went through surprising discoveries that it seemed like it is another RNA virus. It also got into platelets. It was a bit hard to tweak things surrounding BSL-3 to tell you if the response was the same. It is still not very clear how much SARS or rather what receptor, particularly when it gets inside would induce an immune response. There are some literature showing the MDA5, but not for sure, may be responsible. But what we found is that once it gets in platelets, it just induces this profound activation of programmed cell death pathways and release of extracellular vesicles and all these prothrombotic, procoagulant form of content that can induce damage around, because platelets are everywhere. So that how it started in 2019 and surprisingly progressed to 2021 or 2020 without the plan of really studying this virus.   Cindy St. Hilaire:         How similar and how different is what you observe in platelets infected, obviously in the lab, so I know it's not exactly the same, but how similar and how different is it between the flu? Do you know all the differences yet?   Milka Koupenova:       No offense here, they don't get infected.   Cindy St. Hilaire:         Okay.   Milka Koupenova:       Done the proper research. The virus does not impact platelets, but induces the response.   Cindy St. Hilaire:         Okay.   Milka Koupenova:       That goes back to sensing mechanism. Thank goodness platelets don't get infected because we would be in a particularly bad situation, but they remove the infectious virus from the plasma from what we can see with function.   Cindy St. Hilaire:         Got it. So they're helping the cleanup process and in that cleaning up is where the virus within them activates. That is a really complicated mechanism.    Milka Koupenova:       Oh, they're sensing it in some form to alert the environment. It's hard to say how similar and how different they are unless you study them hint by hint next to each other. All I can tell is that particularly with SARS-C, you definitely see a lot more various kinds of extracellular vesicles coming out of them that you don't see the same way or rather through the same proportion with influenza. But what that means in how platelet activates the immune system with one versus the other, and that goes back to the prothrombotic mechanisms. That is exactly what needs to be studied and that was the call for this COVID compendium is to point out how much we have done as a team. As scientists who put heads together, as Mina said, superfast response, it's an amazing going back and looking at what happened to think of what we achieved. There is so much more, so much more that we do not understand how one contributes to all of these profound responses in the organs themselves, such as myocarditis. We see it's important and that will be the problem that we're dealing from here on trying to figure it out and then long COVID, right?   Cindy St. Hilaire:         Yeah. Related to what you just said about the mechanism, this cleanup by the platelets or the act of cleaning up helps trigger their activation, is that partly why the antiplatelet and anticoagulant therapies failed in patients? Can you speculate on that? I know the jury's still out and there's a lot of work to be done, but is that part of why those therapies weren't beneficial?   Milka Koupenova:       The answer to that in my personally biased opinion is yes. Clearly, the antiplatelet therapies couldn't really control the classical activation of a platelet. So what I think we need to do from here on is to look at things that we don't understand that non-classically contribute to the thrombotic response downstream. If we manage to control the immune response in some way or the inflammation of the infection or how a platelet responds to a virus, then perhaps we can ameliorate a little bit of the downstream prothrombotic effect. So it's a lot more for us to trickle down and to understand in my personal opinion.   DeLisa Fairweather:    There is one thing that was really remarkable to me in hearing your experience, Milka, is that I had developed an autoimmune viral model of myocarditis in mice during my postdoc. So I've been studying that for the last 20 years. What is unique about that model is rather than using an adjuvant, we use a mild viral infection so it doesn't take very much virus at all going to the heart to induce it. I also, more recently, started studying extracellular vesicles really as a therapy, and in doing that, inadvertently found out that actually, the model that I'd created where we passage the virus through the heart to induce this autoimmune model, we were actually injecting extracellular vesicles into the mice and that's what was really driving the disease. This is really brought out. So from early days, I did my postdoc with Dr Noel Rose. If you've heard of him, he came up with the idea of autoimmune disease in the '50s. We had always, in that environment, really believed that viruses were triggering autoimmune disease and yet it took COVID before we could really prove that because no one could identify them. Here we have an example and I think the incidence rates with COVID were so high for myocarditis because for the first time, we had distinguished symptoms of patients going to the doctor right at the beginning of their infection having an actual test to examine the virus, knowing whether it's present or not, whether PCR or antibody test, and then being able to see when myocarditis happened.   Cindy St. Hilaire:         Yeah. I think one thing we can all appreciate now is just some of the basic biology we've learned on the backend of this. Actually, those last comments really led well to the article that your team led, Dr Chung, about what we call long COVID, which I guess I didn't realize has an actual name, post-acute sequelae of SARS-CoV-2 or PASC is the now more formal name for long COVID. But what is it? We hinted at it that there's these bits about autoimmune and things like that. What counts as long COVID?   Mina Chung:   Yeah. Our article was led by Tamanna Singh. She did a fantastic job of putting this together. We've had, and others, theorized that the huge palette of symptoms that you can experience post-COVID, they can affect all these organ systems with brain fog, these atypical chest pains, postural orthostatic tachycardia, a lot of palpitations, atrial fibrillation, many weakness and fatigue. To us, really, you can get GI symptoms. We've been very interested in, is this an autoimmune phenomenon directed against nerves and all those things. It's also very interesting because many of the non-COVID syndromes that existed pre-COVID like POTS and chronic fatigue syndrome and a lot of other syndromes are associated with autoantibodies. So that is a very interesting area to explore. Is there a persistence of viral fragments. Is there autoimmunity? Is it also a component of persistence of the damage from the initial infection? So it's an area that still needs a lot of work and a lot of work is going into it, but this is like a post or inter pandemic of itself, so hopefully we'll get more insights into that.   Cindy St. Hilaire:         Yeah, it's really interesting. I have a friend who has very debilitating long COVID and one of her doctors had said, "If I didn't know any better, I would just describe this as a autoimmune type X." What do we know, I guess, about the current hypothesis of the pathogenesis of PASC? Are there any prevailing theories right now as to why it's occurring? Is the virus still active or is it these domino effects that are leading to multi-organ collapse of some sort?   Mina Chung:   Yeah. In some people, persistent viral particles can be identified for months, but whether or not that's what's triggering it, it's hard to know. We see more autoimmune disease that's been reported and various antibodies being reported. So those are clearly processes to be investigated. The microthrombosis is still up there in terms of potentially playing a role in long COVID.   Milka Koupenova:       Mina, you probably know better because you see patients, but to all I have been exposed to, long COVID does not really have a homogeneous symptom presentation and then a few theories as to what may be going on in these patients. Not everybody has a microthrombosis. Not everybody have a D-dimer elevated, but some people do. Some people have, as you pointed out, these spectacularly profound brain fog. People can't function. It's probably your friend, Cindy, right?   Cindy St. Hilaire:         Yeah.   Milka Koupenova:       So one of the theories that I have been, from a viral perspective, very interested in is that a lot of the symptoms in certain individuals such as fatigue, brain fog, sensitivity to light and skin can very well be explained by a flare-up of Epstein-Barr virus that may be what SARS-CoV-2 somehow is inducing. I don't know, DeLisa, what your experience with long COVID is as a scientist. I hope only. But I would like to hear your perspective too because it's so heterogeneous and it is amazing what happens.   DeLisa Fairweather:    I have a very interesting perspective from a number of different directions. One, as I mentioned before, my long history with Dr Rose and I've written many articles theorizing how viruses could cause autoimmune disease. This has grown and really, I think this has been extremely revealing during COVID for many of those theories. One thing that I write about in the review for this article is that mast cells, from all the research I've done with myocarditis in our model, mast cells are central to what is driving everything. We show they're the first innate immune cell acting as an antigen-presenting cell, completely driving the response in a susceptible pattern. One of the things that's very important in autoimmune disease is both sex and race. I'd say one of the big weaknesses we have in myocarditis pre-COVID and post-COVID has been ignoring what's going on with race. In the United States, myocarditis is 90%, 95% white men that are under 50 years of age and most of the cases are under 40 or some of the ones really associated with sudden cardiac death are under 30. So it's very specific. I've been studying sex and race differences and we see those exact differences in our animal models. In animal models, whether you're susceptible or not depends on how many mast cells you have. Well, I've proposed from the beginning, looking, I've written a lot of different sex difference reviews looking at viruses and autoimmune disease with different autoimmune diseases and hypothesizing and really seeing that mast cells do a lot of the things we're talking about. They have all of the receptors, the whole group of them that have been related to SARS-CoV-2 so they can be activated or stimulated by the virus itself. They act as a antigen-presenting cell. They're critical in the complement pathway as well as macrophages. We see the dominant immune phenotype really being macrophages. Mast cells just are usually not counted anywhere. And of course, these receptors, a lot of them have to do with enzymes and things that are all related to mast cells pathways. Then how they activate the immune response and lead it towards the pathway that leads to chronic autoimmune disease with increased autoantibodies in females, mast cells are very different by sex. This has to do also when we talked in the Review about myocarditis and pericarditis. It's both those appearing. Although clinically, we have really boxed them as separate things, because there is some definite clinical pericarditis phenotypes that are different, myocarditis in animal models is always myopericarditis. It always then, in that outer pericardial areas where mast cells sit, they sit around the vascular area in most concentrated. So when they degranulate, we see inflammation coming in the vessel, but really concentrated with fibrosis there and along the pericardium. So that's very typical of what's going on. When we shift anything that shifts that, it changes whether you have more pericarditis or less pericarditis and the vascular inflammation by altering anything that affects the mast cells. I talk a little bit about in the review, I think there's only been a few recent things looking at it in COVID, but I think mast cells and certain susceptibility to autoimmune diseases that occur more often in women can really predispose.We need to pay more attention to mast cells and what they might indicate for all these pathways.   Milka Koupenova:       I think we should study the platelet mast cell access at this point.   DeLisa Fairweather:    Yes.   Milka Koupenova:       Because as you're talking about these sex differences, which is spectacular, these things to me are so mind-boggling how one, the infection itself would be more prevalent in men, but then long COVID is more prevalent in women. All of these things and why we understand so very little, what we found about a few years ago in the Framingham Heart Study in the platelets from those people is that all toll-like receptors are expressed at the higher level in women and they associate with different things between men and female. For instance, toll-like receptors in women will associate more with a prothrombotic response while in male with pro-inflammatory response. I think they grossly underestimate the amount of our sex differences from cell to cell.   DeLisa Fairweather:    It is, yeah.   Mina Chung:   One other thing that I learned about the sex differences from this compendium is Mark Chappell also notes, you mentioned TLR and TLR7 and ACE2 are X chromosome in an area that he says escapes X-linked inactivation. So it could very well be involved in further.   DeLisa Fairweather: Further, yeah. And ACE2 is expressed more highly in male cells for what's been researched because of the sex difference in COVID, both the COVID infection   Cindy St. Hilaire:         So a variety of organ systems are impacted in patients with PASC, also referred to as long COVID, the lungs, the heart, the pancreas, the GI system, pretty much any system, the brain, nervous system. We've just been talking about the mast cell impact. I was really thinking in my head, well, the one thing that connects all of it is the vasculature. I'm a vascular biologist, so I have certain biases, I'm sure, but how much of the sequelae that we see is a function of vascular phenotypes?       Milka Koupenova:       I do think the vasculature is super important. It's clear that not all endothelial cells, for instance, will pick up the virus and respond to it. That's why you have this patchy breakage when you look at autopsies. Hence, platelets will respond according to what's local. That's why you find these micro thrombotic events at certain places. Why does it happen in each organ? How does the virus get to each organ to respond? Or is it just inflammation, but why is it in specific places? That's what we don't understand. That's where we need to go. Perhaps, as DeLisa points out, perhaps it's a lot more complicated than how we traditionally think of thrombosis. Actually, my personal bias, again 100% sure that it is a lot more complicated than the traditional mechanisms that we have understood, and that's where the immune system comes and autoimmunity perhaps stems from and they probably speak to each other, right? It's not just one thing.   DeLisa Fairweather:    Yeah. I think really, EVs are bringing lots of understanding. A lot of things we used to just think were maybe free-floating and the serum are inside EVs. I think that the immune response is perhaps even more specific than we ever thought and more regulated than we ever understood.   When an EV comes through a cardiomyocyte, whether it's from the mitochondria or through a lysosome, is part of what goes into its outer membrane, something that tells the immune system that that came from the heart, so it knows to go. This will solve a lot of our questions with autoimmune disease if it's very specific like that. It doesn't just have to be the release of free-floating cardiac myosin. We know cardiac myosin is the driver of the autoimmune response in myocarditis, but they're probably  much more fine-tuned.   Cindy St. Hilaire:         Yeah. I just would love to end with hearing from each of you. You each have your own domain of specialty. If I gave you a massive pot of money, what would be the question you would want to tackle? What's the gap you would love to answer?   Milka Koupenova:       We still don't understand specifically what kind of vesicles are coming out, what are their contents in addition to those vesicles. We don't understand. When it comes to platelets, what comes from their granules? We see these breakages of the membrane. Those are non-granule proteins, and non-granule proteins, they serve as dangerous associated molecular pattern signals and can be profoundly inflammatory to the surrounding environment, can be procoagulant. What are those? How are they affecting the surrounding environment? Ultimately, why is there a microthrombi? Why is there not a profound thrombosis everywhere? Thank goodness there isn't, but why isn't? That's what I would do with my money.   DeLisa Fairweather:    I think I would do something very similar. All of our research in our animal model, on the one side, we are looking in this viral myocarditis animal model and finding the EVs that come from that are driving myocarditis. On the other hand, we're using EVs that come from healthy human plasma or fat, and we're seeing a profound downregulation of everything if you give it early and we're trying to see how late you can give it and still get an effect. So looking at those and really understanding the components in the context of COVID and COVID vaccines to understand those components, I really think that's the future of where we're going to find what's causing disease and also how we can find therapies. They may be able to reverse this.   Mina Chung:   Yeah, I'm interested very much in the autoimmunity and the autoantibodies that are    and how they may react with those microthrombi. Perhaps there's autoantibodies within a lot of that material. We're looking at using human and pluripotent stem cell-derived cell models to study the effects of those. That is what I would use our money for.   Cindy St. Hilaire:        Well, Dr Mina Chung, Dr DeLisa Fairweather, Dr Milka Koupenova, thank you all so much for joining me today and talking about not only the articles that you wrote and with your colleagues, but also other articles in this amazing compendium. I do think this is one of the first all-encompassing compendiums or group of articles that focus specifically on COVID and cardiovascular disease. So thank you all so much.   Mina Chung:   Thank you.   DeLisa Fairweather:    Thank you.   Milka Koupenova:       You're welcome.   Cindy St. Hilaire:         That's it for highlights from the April 28th and May 12th issues of Circulation Research. Thank you for listening. Please check out the CircRes Facebook page and follow us on Twitter and Instagram with the handle @circres and #DiscoverCircRes. Thank you to our guests, Dr Mina Chung, Dr DeLisa Fairweather and Dr Milka Koupenova. This podcast is produced by Ishara Ratnayaka, edited by Melissa Stoner and supported by the editorial team of Circulation Research. Some of the copy text for the highlighted articles is provided by Ruth Williams. I'm your host, Dr Cindy St. Hilaire, and this is Discover CircRes, your on-the-go source for the most exciting discoveries in basic cardiovascular research. 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 information, visit ahajournals.org.    

Le fait a encore une fois été remarqué pendant la récente épidémie de Coronavirus. En réanimation, les lits d'hôpital étaient occupés plus fréquemment par des patients masculins que féminins. Sur le tableau des décès des suites du Covid-19, la proportion d'hommes atteint 57,8% en France contre 42,2% de femmes, une tendance confirmée dans tous les pays relevés, sauf le Vietnam et la Corée du Sud.Les femmes résistent mieux aux infections que les hommes, et ce point a été à nouveau confirmé par une étude récente, qui ajoute que l'âge n'influence pas ce constat. Une femme de 80 ans sera toujours mieux armée face aux virus qu'un homme du même âge.L'influence des interférons de type 1Grippe, VIH, SARS-Cov2 : qu'ont en commun ces infections ? D'après les statistiques médicales obtenues sur les dernières décennies, les femmes résistent mieux à ces virus que les hommes. Le mécanisme impliqué dans cette différence est connu depuis longtemps, et se base sur une composante génétique.Il faut d'abord savoir qu'en cas d'infection par un virus de type grippe ou Covid-19, certaines cellules du corps détectent la présence de l'indésirable grâce à un récepteur nommé TLR7. Ces cellules relarguent alors dans le sang des molécules antivirales, les cyotkines, dont l'une porte le nom d'interféron de type 1. Puissants et aptes à stopper la réplication du virus, les interférons ont un rôle crucial dans la lutte contre l'infection. Il s'avère que les femmes produisent généralement davantage d'interférons que les hommes lors de la stimulation du récepteur TRL7, pour une bonne raison : le gène qui code ce récepteur est situé sur le chromosome X, que les femmes possèdent en double exemplaire.Les études qui avaient été menées jusqu'à récemment portaient surtout sur des femmes de moins de 60 ans. Mais, en 2022, des chercheurs de l'Inserm, du CNRS et de l'université Toulouse 3 ont collaboré pour étudier la réponse immunitaire de l'organisme chez les femmes plus âgées... Hébergé par Acast. Visitez acast.com/privacy pour plus d'informations.

Le fait a encore une fois été remarqué pendant la récente épidémie de Coronavirus. En réanimation, les lits d'hôpital étaient occupés plus fréquemment par des patients masculins que féminins. Sur le tableau des décès des suites du Covid-19, la proportion d'hommes atteint 57,8% en France contre 42,2% de femmes, une tendance confirmée dans tous les pays relevés, sauf le Vietnam et la Corée du Sud. Les femmes résistent mieux aux infections que les hommes, et ce point a été à nouveau confirmé par une étude récente, qui ajoute que l'âge n'influence pas ce constat. Une femme de 80 ans sera toujours mieux armée face aux virus qu'un homme du même âge. L'influence des interférons de type 1 Grippe, VIH, SARS-Cov2 : qu'ont en commun ces infections ? D'après les statistiques médicales obtenues sur les dernières décennies, les femmes résistent mieux à ces virus que les hommes. Le mécanisme impliqué dans cette différence est connu depuis longtemps, et se base sur une composante génétique. Il faut d'abord savoir qu'en cas d'infection par un virus de type grippe ou Covid-19, certaines cellules du corps détectent la présence de l'indésirable grâce à un récepteur nommé TLR7. Ces cellules relarguent alors dans le sang des molécules antivirales, les cyotkines, dont l'une porte le nom d'interféron de type 1. Puissants et aptes à stopper la réplication du virus, les interférons ont un rôle crucial dans la lutte contre l'infection. Il s'avère que les femmes produisent généralement davantage d'interférons que les hommes lors de la stimulation du récepteur TRL7, pour une bonne raison : le gène qui code ce récepteur est situé sur le chromosome X, que les femmes possèdent en double exemplaire. Les études qui avaient été menées jusqu'à récemment portaient surtout sur des femmes de moins de 60 ans. Mais, en 2022, des chercheurs de l'Inserm, du CNRS et de l'université Toulouse 3 ont collaboré pour étudier la réponse immunitaire de l'organisme chez les femmes plus âgées... Learn more about your ad choices. Visit megaphone.fm/adchoices

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.01.06.523014v1?rss=1 Authors: Liu, T., Wang, H., Kutsovsky, D. Y., Ohn, C. Y., Patel, N., Yang, J., Simon, D. J. Abstract: Inflammation is closely associated with many neurodegenerative disorders. Yet whether inflammation causes or exacerbates neurodegeneration has been challenging to define because the two processes are so closely linked. Here we disentangle inflammation from the axon damage it causes by individually blocking cytotoxic T cell function and axon degeneration. We model inflammatory damage in mouse skin, a barrier tissue that, despite frequent inflammation, must maintain proper functioning of a dense array of axon terminals. We show that sympathetic axons control skin inflammation through release of norepinephrine, which suppresses activation of gamma delta T cells via the beta2 adrenergic receptor. Strong inflammatory stimulation in the form of the toll like receptor 7 (TLR7) agonist imiquimod (IMQ) causes progressive gamma delta T cell-mediated, Sarm-1-dependent loss of these immunosuppressive sympathetic axons, a positive feedback loop that removes a physiological brake on T cells, resulting in enhanced inflammation and inflammatory axon damage. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

W tym odcinku opowiadam o pamiętaniu snów, energetyzującej kofeinie, oceanicznych wędrówkach żółwi i gigantycznych liściach, przyglądam się genom oraz ryzyku związanemu z zanieczyszczeniami powietrza.A jeśli uznasz, że warto wspierać ten projekt to zapraszam do serwisu Patronite, każda dobrowolna wpłata od słuchaczy pozwoli mi na rozwój i doskonalenie tego podkastu, bardzo dziękuję za każde wsparcie!Zapraszam również na Facebooka, Twittera i Instagrama, każdy lajk i udostępnienie pomoże w szerszym dotarciu do słuchaczy, a to jest teraz moim głównym celem :)Źródła użyte przy tworzeniu odcinka:Vallat R, Türker B, Nicolas A, Ruby P. High Dream Recall Frequency is Associated with Increased Creativity and Default Mode Network Connectivity. Nat Sci Sleep. 2022;14:265-275, https://doi.org/10.2147/NSS.S342137Eric W. Dolan, "Heightened dream recall ability linked to increased creativity and functional brain connectivity", https://www.psypost.org/2022/05/heightened-dream-recall-ability-linked-to-increased-creativity-and-functional-brain-connectivity-63139Josey Murray, "Let's Look At The Science: How Long Does Caffeine Stay In Our System?", https://www.mindbodygreen.com/articles/how-long-does-caffeine-lastBrown, G.J., Cañete, P.F., Wang, H. et al. TLR7 gain-of-function genetic variation causes human lupus. Nature 605, 349–356 (2022). https://doi.org/10.1038/s41586-022-04642-zManuel Ansede, "One girl's genetic mutation sheds light on the causes of lupus", https://english.elpais.com/science-tech/2022-04-28/one-girls-genetic-mutation-sheds-light-on-the-causes-of-lupus.htmlGraeme C. Hays, Nadine Atchison-Balmond, Giulia Cerritelli, Jacques-Olivier Laloë, Paolo Luschi, Jeanne A. Mortimer, Alex Rattray, Nicole Esteban, "Travel routes to remote ocean targets reveal the map sense resolution for a marine migrant", https://doi.org/10.1098/rsif.2021.0859David Nield, "We Just Got Closer to The Secret of How Turtles Navigate in The Open Ocean", https://www.sciencealert.com/turtles-have-an-uncanny-knack-for-pinpointing-islands-in-the-ocean-but-it-s-mostly-luckFinn Box, Alexander Erlich, Jian H. Guan, Chris Thorogood, "Gigantic floating leaves occupy a large surface area at an economical material cost", https://doi.org/10.1126/sciadv.abg3790Renjie Chen, Yixuan Jiang, Jialu Hu i inni, "Hourly Air Pollutants and Acute Coronary Syndrome Onset In 1.29 Million Patients", https://doi.org/10.1161/CIRCULATIONAHA.121.057179Photo by Jessica Lewis on Unsplash

Un nuevo estudio publicado el pasado mes de abril en la prestigiosa revista Nature ha descrito una paciente que sufre lupus y que presenta una mutación en el gen TLR7, confirmando los estudios anteriores en modelos animales. Los análisis de esta mutación han permitido que un grupo de investigadores pudieran replicar la mutación de forma exacta en un modelo de ratón. Este modelo ha revelado que no sólo la mutación es esencial, sino que las moléculas que se unen a este receptor, TLR7, son importantes para provocar los síntomas.Suscríbete a Muy Interesante https://suscripciones.zinetmedia.es/mz/ Guión: Marta González Pérez-IñigoLocución, producción y diseño sonoro: Iván Patxi Gómez GallegoContacto de publicidad en podcast: podcast@zinetmedia.es

Researchers from The Australian National University (ANU) have identified a gene called TLR7 that, when over-activated, is responsible for causing lupus, an autoimmune disease that can be life-threatening in severe cases.   - Μια σημαντική επιστημονική ανακάλυψη ανακοινώθηκε πρόσφατα, από το Αυστραλιανό Εθνικό Πανεπιστήμιο (Australian National University), και πιο συγκεκριμένα από ερευνητική ομάδα, του John Curtin School of Medical Research.

This month on Episode 28 of Discover CircRes, host Cynthia St. Hilaire highlights four original research articles featured in the August 20th and September 3rd issues of Circulation Research. This episode also features an in-depth conversation with Dr Scott Cameron from the Cleveland Clinic and Dr Milka Koupenova from the University of Massachusetts Medical Center about their study, SARS-CoV-2 Initiates Programmed Cell Death in Platelets.   Article highlights:   Gupta, et al. Electronic Cigarettes and Oxidized Lipids   Bartosova, et al. Glucose Derivative Induced Vasculopathy in CKD   Atmanli, et al. DMD Correction Attenuates Cardiac Abnormalities   Ma, et al. Length Dependent Activation in Porcine Myocardium   Cindy St. Hilaire:        Hi, and welcome to Discover CircRes, the podcast for the American Heart Association's journal, Circulation Research. I'm your host, Dr Cindy St. Hilaire from the Vascular Medicine Institute at the University of Pittsburgh, and today I will be highlighting articles presented in our August 20th and September 3rd issues of Circulation Research. I also will speak with Dr Scott Cameron from the Cleveland Clinic and Dr Milka Koupenova from the University of Massachusetts Medical Center about their study, SARS-CoV-2 Initiates Programmed Cell Death in Platelets. Cindy St. Hilaire:        The first article I want to share is titled Electronic and Tobacco Cigarettes Alter Polyunsaturated Fatty Acids and Oxidative Biomarkers. The first author is Rajat Gupta and the corresponding author is Jesus Araujo from UCLA. E-cigarettes have surged in popularity in the last decade and while many people switching from traditional cigarettes to smokeless ones view the latter as a safe alternative to smoking tobacco, emerging data shows that E-cigarettes cause adverse effects such as oxidative stress, inflammation and endothelial dysfunction in users. The aerosols produced during vaping contain similar levels of reactive oxygen species, also called ROS, as the vapors of tobacco smoke. However, data on the extent to which E-cigarettes, E-cigarette ROS, influences cardiovascular health is lacking. Cindy St. Hilaire:        To address this, this group recruited 32 chronic users of E-cigarettes, 29 chronic tobacco smokers, and 45 individuals that used neither and they measured their plasma levels of oxidative biomarkers. The team found both similarities and differences between the E-cigarettes and the tobacco users. For example, both smoking groups had increased plasma antioxidant capacity and decreased levels of oxidized linoleic acid compared with the levels seen in non-users, while arachidonic acid levels were raised in tobacco smokers and reduced in E-cigarette users. Overall, however, the biomarker levels were deemed to be intermediate for E-cigarette users between the non-users and the tobacco users. This study suggests that while E-cigarettes carry a lower health risk than tobacco, they are by no means safe.     Cindy St. Hilaire:        The second article I want to share is titled Glucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal Dialysis. The first author is Maria Bartosova and the corresponding author is Claus Schmitt and they're from the University of Heidelberg. Diabetes, high blood pressure and obesity are risk factors for both cardiovascular disease and chronic kidney disease. Worse still, loss of kidney function and even dialysis itself are thought to exacerbate cardiovascular issues. In the case of dialysis, it's thought that high levels of glucose degradation products, or GDPs, in the dialysis fluids can promote the addition of sugar moieties to vascular proteins and lipids causing vascular damage. To investigate this theory, Bartosova and colleagues studied vascular tissue from children with chronic kidney disease receiving dialysis fluids with either high levels or low levels of glucose degradation products and compared these to tissues from children not on dialysis at all. Cindy St. Hilaire:        Proteome and transcriptome analysis of the vessel tissues revealed that compared with patients or no to low GDP fluids, patients receiving high GDP fluids had higher levels of damaging glycation, increased transcription of genes involved in cell death, and decreased transcription of genes involved in cell survival and cytoskeletal reorganization. In line with these findings, vessels from high GDP patients displayed considerable evidence of damage, such as markers of apoptosis, skeletal disintegration and thickened intimas. The results confirmed GDPs can cause vasculopathy and suggest low GDP fluids should be used for dialysis patients. Cindy St. Hilaire:        The next article I want to share is titled Cardiac Myoediting Attenuates Cardiac Abnormalities in Human and Mouse Models of Duchenne Muscular Dystrophy. The first author is Ayhan Atmanli and the corresponding author is Eric Olson from UT Southwestern. Duchenne Muscular Dystrophy, or DMD, affects one in 5,000 baby boys and is caused by mutations in gene for dystrophin, an architectural protein essential for muscle cell integrity. Patients display profound muscle degeneration and weakness, with respiratory and heart muscle dysfunction being a major cause for death. With the recent improvements in respiratory medicine that extend the lives of patients, this group now focused on heart dysfunction and specifically, whether gene editing could mitigate it. The team created induced pluripotent stem cells, or iPSCs, from Duchenne Muscular Dystrophy patient and his healthy brother and showed that gene editing from the DMD cells enabled their development into normal-looking cardiomyocytes with normal contractile function and calcium handling, equivalent to that seen in healthy control cells. The unedited DMD cells, by contrast, did not develop normally. For great clinical relevance, the team edited DMD cells after cardiomyocyte differentiation showing that this reduced their propensity for arrhythmia, compared with that of unedited cells. Cindy St. Hilaire:        Lastly, the team provided evidence to suggest gene editing may improve heart abnormalities in mice with the same mutation. All together the results are proof of principle and support of the development of gene editing therapy as treatment for DMD. Cindy St. Hilaire:        The last article I want to share is titled The Super-Relaxed State and Length Dependent Activation in Porcine Myocardium. The first authors are Weikang Ma and Marcus Henze and the corresponding author is Thomas Irving and they're from the Illinois Institute of Technology. Myofilament length-dependent activation or LDA is the fundamental mechanism coupling the force of the heart's contraction to it's proceeding diastolic volume. In other words, LDA ensures that the more the heart fills, the stronger it contracts. Studies of rodent hearts have given insights into LDA mechanics. However, how it operates in large mammalian hearts is unknown. Using structural and biochemical analysis of pig myocardial fibers, this group found that compared with small stretches of the fibers which were equivalent to small diastolic volumes, long stretches induced greater ATP turnover and greater numbers of cross bridges between myosin and actin filaments which are critical contractile machinery proteins. Cindy St. Hilaire:        Myosin motors can be found in three stages, engaged with actin, unengaged in a disordered, relaxed state but ready to engage, or super-relaxed state where they are essentially switched off. The team showed that as muscle stretch increased, the amount of super-relaxed myosin motors diminished with more myosin motors becoming engaged to enable a stronger contraction. When the fibers were treated with a myosin motor inhibitor, these stretch effects were impaired. In revealing the mechanisms of myofilament length-dependent activation, this study provides a platform for studying cardiomyopathies in which this system goes awry. Cindy St. Hilaire:        So today, Dr Scott Cameron from the Cleveland Clinic and corresponding author of the paper, Dr Milka Koupenova from the University of Massachusetts Medical Center, are both with me to discuss their study, SARS-CoV-2 Initiates Programmed Cell Death in Platelets. And this article is in our September 3rd issue of Circ Research and for full disclosure, the editor of Circ Res, Dr Jane Freedman is also an author on this manuscript. And for full double disclosure, I know Dr Koupenova quite well as we were both graduate students together back in the Ravid Lab at Boston University. However, the full Editorial Board selects these articles, not just me alone and this one is timely, novel, and an amazing story. So thank you both for joining me today. Milka Koupenova:       Thank you for having us. Scott Cameron:           Privileged to be here. Cindy St. Hilaire:        So before we jump into the story that is your paper, can you give us a little bit of background about platelets? I know for years, I guess certainly before Katya's lab, I just thought of platelets as little nucleus-free particles that clot. But we know they are so much more than that. So why are they so important? And how do they function to do more than just stop a bleed? Milka Koupenova:       So this is a great question, Cindy, and I am happy that you alluded exactly to the anucleated nature of platelets. So platelets are cell fragments. They're precursors in the bone marrow, the megakaryocyte. They are the second most abundant blood component after the red blood cells. And traditionally, platelets have been known, as what you pointed out, as these little units that change their conformation once there is some form of a problem with either the vascular, which we have a cut, they come together, they form this clot, and bleeding is prevented. But as we have learned perhaps in the past 20 years that platelets have a profound immune role during various immune processes and infections for different kind of microbes. And particularly relevant to this paper is that we understand that platelets have clearly a role responding to the viruses and activating the immune system. Cindy St. Hilaire:        Yeah, and that was actually my next question. You and Jane are the world-leading experts on platelets and viral responses. So what was known about that interaction, I guess before we started looking at SARS-CoV-2, what was known about that platelet virus or even type of virus interaction? Milka Koupenova:       So SARS-CoV-2 is a RNA virus--respiratory virus that we actually thought similarly to influenza that it mostly stays in the lower respiratory tract where it becomes problematic. However, from our work with influenza, when we saw that in certain patients you actually can detect the virus in platelet. In the beginning of the pandemic, we hypothesized that perhaps, in some people, the virus crosses over into the circulation. And based on our previous studies with influenza, we wanted to see if that indeed is the case. Hence we initiated a study here at UMass with the department head who is also on the paper, Dr Finberg, who is a leading expert in influenza and novel virus and we collected platelets from people to see if we can detect it. And so in the beginning, we were not able to detect SARS-CoV-2 in platelets. So we collected platelets from 17 patients and by qPCR with the primers that the CDC has, for whatever reason I couldn't detect anything. And I was really frustrated because previous reports have shown that about 25%, in some people even 35% of the study population, SARS can be detected. So very interesting observations. Milka Koupenova:       I could see it by immunofluorescence but I couldn't detect the RNA. And the story goes, that I attended a seminar on SARS-CoV-2 and the person was actually referencing a company that started from University of Pitt where you are. Cindy St. Hilaire:        Oh, very nice. Milka Koupenova:       And they do specific, it's called amplicon ARTIC v3 sequencing so they enrich for the SARS-CoV-2 RNA and screen by sequencing. And when we did that, we were able to detect it in all patients. So I freaked out and I said, "Oh my gosh, something is wrong." Milka Koupenova:       And so I sent plasma, and I sent controls, and actually RNA from the virus and you can see beautifully that it's only in platelets. Four of the 17 people actually had RNA in the plasma, but what you can observe in all these people is that the virus is fragmented, meaning it's not infectious. And in a way what this tells us, it suggests that platelets are super important in the removing it from the circulation and they probably serve as a dead-end for the virus because you cannot find virus coming out of platelets and the RNA is chopped off. So what I would say, is that platelets are these amazing little units that serve as removal of the viral RNA for these particular viruses, respiratory viruses that are RNA viruses. Cindy St. Hilaire:        I think that is so interesting. So essentially, they're almost like little composters that are chewing it up and preventing it from spreading in the organism. Milka Koupenova:       Yes, and as a result there is a response. Cindy St. Hilaire:        Scott, probably the most common thing that people know with SARS is that loss of smell, or taste, and things like that, but really that doesn't send anybody to the hospital. So really what are the symptoms of COVID-19 patients that tie in with platelets specifically? I feel like that's a lot of things that we maybe in the public, or on Twitter, and things didn't hear as much about. So really what are those big symptoms linking COVID and platelets and what are the implications of platelet death in the pathogenesis of COVID? Scott Cameron:           So certainly I think several investigators are in the world of now showing that platelets are hyperactivated, Robbie Campbell and Matt Rondina put a really nice paper in Blood last year showing that platelets are hyperactive and there are other investigators who found something similar. And so the question is, what are the symptoms of hyperactive platelets in the SARS-CoV-2 patient? So what most of them would find is shortness of breath or dyspnea, and when they present to the emergency department, and certainly we saw this, the oxygen saturation which should be in the mid to high 90s on room air on an average person, was quite often low. It was in the 80s or 70s, sometimes even the 60s. Scott Cameron:           And the real surprising thing was those are patients that would normally immediately be on a ventilator, but yet they could still be talking to you. And so if you have a platelet that's activated in a hyperthrombotic condition, like SARS-CoV-2, COVID-19, and then that forms a blood clot, you have a situation where the amount of oxygen the patients taking in and the amount of oxygen you're measuring in the artery is quite discrepant and we call that the alveolar arterial or oxygen gradient. So if you've got lots of platelet plugs through the microvasculature, it's going to take up some space the oxygen should be using for diffusing in. And so that would be manifested as shortness of breath and that's certainly one of the biggest tip-offs that a patient might have a blood clot, particularly in the lung. Cindy St. Hilaire:        Some of these symptoms of COVID-19 are really worse in patients with comorbidities, diabetes, obesity and heart failure. Are platelets central to kind of the pathogenesis of those disease or the symptoms of those diseases? I guess the root of my question is, why do the comorbidities of diabetes, obesity, and heart failure make COVID worse? Is it something about those disease states themselves or is there a role for platelet? Scott Cameron:           That's a brilliant question, no one's ever asked that before. And as Dr Koupenova said, I'm a little bit biased too because I firmly believe that in different disease states, the disease educates the platelets so you've got a different platelets phenotype. So focusing on diabetes, we know the platelet phenotype is different in diabetic patients. We know that platelet reactivity seems to be higher through the P2Y12 receptor.  In terms of obesity, it is true, we know that, and this has been published also, and we know that the platelet phenotype is hyperactive in a patient with obesity and so that tells me that, that's a comorbidity that might affect platelet function and also vice versa for that case. And then in terms of why is it affecting males more prominently and more severely than females, well one of the beefs, I guess, that I had is that we treat diseases in women the same as we do in men assuming that the platelet phenotype in disease must be the same, but that's absolutely not true. And that's actually a theme that we have in our lab right now, we know that the behavior of platelets, and how platelets are educated in diseases is not all the same in women as in men and I think it's a huge disservice that we really had to have a pandemic that would make that quite clear to us. Cindy St. Hilaire:        You kind of hit onto something that's really, I think it's now becoming more recognized certainly in the cardiovascular field and that is so many studies are really only on male mice, or only younger or older men, and we are missing not only a huge patient population, but probably some really interesting biology that is distinct. Milka Koupenova:       So expanding on that, we know that in platelets, the toll-like receptors, and we've looked at the expression of all 10 in a study that we published in ATVB in 2015, actually, significantly if you look at Farmingham Heart Study data and the expression of these toll-like receptors they are increased in women versus men. And also, an interesting observation that never got published, once upon a time when I was doing studies with TLR7 mice is that if you inject TLR7 agonists, male mice would have a higher level of reduced platelet count than female mice at the same time points, right? And at that time it wasn't published. Definitely there are differences, but I also want to extrapolate a little bit on what was said at the beginning. We have to understand that when it comes to these comorbidities, everything affects a unit that doesn't have a nucleus, right? And diabetes and obesity have the so called profound, chronic inflammation of cytokines, such as IL6, that keep circulating. These things have effect on platelets. So we have two responses, we have the environment that affects platelets and we have the direct response of the virus that affects platelets. And that cumulative response truly can exhaust them and once they become exhausted, once they release their contents, as we show in this paper, then you're compromising their function and you will be compromising taking out the virus from one side and from the other side you're going to be compromising the environment because all of the content that comes out from a unit that already has free form proteins, it exhibits a true insult on what's being surrounded. So these clots that form in the lung or the platelets that circulate they no longer can be resolved properly. Cindy St. Hilaire:        Yeah. Milka Koupenova:       It's a balance. Cindy St. Hilaire:        Yeah, so really it's like destroying the platelet not only are you destroying the vacuum that has to suck up those particles, you're then just dumping a whole bunch of pro-inflammatory things on all of the endothelial cell vasculature that those platelets are nearby. Cindy St. Hilaire:         Actually that was one thing that I thought you spent a decent portion of the discussion on, and that is the method by which the blood is collected really impacts the outputs you observe in quote unquote platelets. Can you talk about the importance of that because I think that's one thing, certainly as a PhD who's just like, "Oh, yeah. I'm just going to collect blood from my mice and do this thing," how critical is that point in the experiment, in the blood collection? Milka Koupenova:       So I am very adamant when it comes to platelets for the blood to be drawn in citrate. And I have to say that a lot of the studies that you would see in the literature are done using EDTA blood or serum. They all have their importance. I'm not going to dismiss it, but if you want to truly measure what's inside in plasma, versus what's inside in platelets, or what's inside in any cell for that matter, you got to go for citrate. You have to be very careful not to shake the blood. You have to be very careful not to cool down the blood. So the nurses probably hated me because often I would be like, "You can't do this. You can't put it on ice. You can't warm it up to above certain degrees. Everything has to be controlled and done correctly." Milka Koupenova:       And so I had done in the past studies in which I would take plasma from the same patient in EDTA, in citrate and then isolate the RNA, have my tech isolate the RNA, and we send it to a fragment analyzer, and you can see how much more RNA you will get in the EDTA plasma. I'm not even talking about serum. Milka Koupenova:       Serum is a very different thing, then you're definitely going to get platelet content in it, in the serum, right? So it's important to distinguish that perhaps when you're getting EDTA plasma you are looking at a content that could have been inside in platelet and I can't stress enough that when it comes to these particular studies, citrate, dextrose, phosphate is your place to go and be. Cindy St. Hilaire:        So in terms of translational potential, what do your findings suggest about future therapies or targets to investigate as therapy? And is modulating platelets a potential for combating viral infections or mitigating their severity? Milka Koupenova:       Well, Scott and I actually talk a lot about that. Scott Cameron:           That's right. Milka Koupenova:       I personally would say, control the inflammation, never let it go to platelet. Let me back up a little bit, if you have to, you have to, right? But your go to method should be inflammation, if you don't get to the point that you need to control platelets then you're in a better place because it becomes very fickle. From everything that you hear me say, you push it to one side and the balance is destroyed. You deactivate platelets or inhibit platelets well, are they now not able to pick up the virus and then you're now having the virus circulating somewhere. Now, if you don't treat platelets that's also not good. So you're in the very fickle situation if you get to the point that you need to control the activation of platelets and there are trials currently that are trying to look at those things. Scott, I'm going to refer this a little bit more to you because you have done some interesting things with that particular point. Scott Cameron:           No, it's a great question, Milka, and I think that as platelet biologists, nobody more than I wanted it to be true that platelets would be the ultimate target. I mean, clearly patients with SARS-CoV-2 have thrombosis, clearly platelets are activated, so should we inactivate them? That was the whole point of the RECOVERY trial and one of the benefits I'll tell you before I sort of go into that is, working in a large organization like the Cleveland Clinic and we have access to data and lots of it extremely quickly, and so because of that I of course could see how many patients were coming into our hospital with thrombotic events. And I could see what the independent predictors of thrombotic events was and it wasn't the platelet count, sometimes platelet count was low, sometimes it's high in the SARS-CoV-2 patient. And if you took those individuals that were on aspirin, comparing them to those that are not in a propensity match study,  one of the things that we find is that aspirin doesn't seem to affect or improve mortality or the number of blood clots in the patient with SARS-CoV-2. Scott Cameron:           We compared that to all non-steroidal anti-inflammatory medications that patients may have been taking also in a propensity match study just in case it was the mechanism action of the drug, rather than the drug itself, and we found that NSAIDs not only did not protect patients, but they were not necessarily harmful either, which was one of the things that came out at the start of the pandemic. Among, I'll add, the absence of evidence based medicine and a lot of cases where naturally people, including clinicians, were scared and so they were going off label and they were trying a lot of different medications with really not a shred of randomized controlled data. Scott Cameron:           But now that we're 18 months into it, the first and biggest study that came back was the RECOVERY trial, which we were all waiting on, where patients were given aspirin and short term mortality was examined over an observational period of one month. And just like we found in a propensity match study, which is as close as you'll get to a clinical trial in a retrospective manner, the prospect of RECOVERY trial actually showed the curves were almost super imposeable, those that got aspirin versus those that didn't. So I think low dose aspirin clearly is not going to be enough for those patients, but I'll also add that over the observational period of one month they also didn't see a higher incidence of death in those patients. And I think Milka's point is really well taken that you have to remember that as well being an entity of thrombosis, platelets are immunological entities and so you've got to really consider should we be inhibiting them and if you are inhibiting them, I think the time point at which you should inhibit them is what we should examine, not just an all or nothing, inhibited or not. Milka Koupenova:       It's just in our linear brains we prefer to think of it as one straight, linear pathway, but it isn't, and I think platelets are actually a great example of how many pathways are feeding into one tiny fragment and that particular blood cell is inducing this profound response during these infections. Cindy St. Hilaire:        I think most people have heard that angiotensin-converting enzyme 2, also called ACE2 is the receptor of SARS-CoV-2. The virus itself uses it to bind and become internalized into the cell, but there's been some discussion or even some discrepancy of data as to whether platelets truly express ACE2 and if that is the means for the virus to enter the platelets. So can you share with us what is the current state of knowledge about that? Scott Cameron:           Yeah, just as a segue of some of the things that Milka said, I think the preparation of your sample is part of the answer. If you draw in the incorrect tube, if you the tube is not completely filled, and the ratio of citrates to whole blood isn't correct you're going to have discrepant results. If you biomechanically activate the platelets by drawing through a short needle, in a small-bore needle for example, that's going to activate the platelets. If you cool them, it's going to activate them. But then also, depending on how you decide to separate them, we always washed platelets in my lab, we wash them two or sometimes three times, and I can tell you if you use flow cytometer we get one white blood cell for every 12,000 platelets. Scott Cameron:           And some investigators might go one step further and they'll a CD45 depletion set, which is certainly important if you're studying RNA. But one of the issues, as you well know, a CD45 is also on the surface of platelets, so if you start with a low expressing protein and you CD45 deplete them, you are actually going to get a decrease in your platelet yields. I've seen it, I think Milka's seen it, various other investigators have, and you might find yourself at the threshold of what your antibody can detect. It's also variably expressed. If you look at even healthy individuals, some of them have almost none. So if you look at 10 individuals, you might actually find none, but then if you look at another 10, the amount of expression that we see is kind of all over the place. It's not like other receptors where one tends to express a certain amount and that's the way it is in health. ACE2 doesn't seem to be that way for whatever reason. Milka Koupenova:       We were able to detect in some of the people by qPCR, but what was interesting is that from the three primers that I used there was never the same person who we were able to detect all three primers with for that receptor. That tells you that maybe they are changes of one base that is not enough for the primer to detect it, right? That becomes another possibility of not being able to detect. Milka Koupenova:       And so I go to confocal microscopy where I use 100 lens and tons of hours in the microscope room, and Scott is completely right, it's really hard to see it particularly in healthy people. And it starts to pick a little bit more in people with cardiovascular disease or people with COVID that are old. So it's a bit complicated, but the important thing here is, besides the fact that we are detecting ACE2 and we're detecting proteins and I use controls, biological controls to prove that this is the case and it's not just an antibody problem, is that the virus will get picked up by platelets even if you don't have ACE2. That is the take home message from this paper is that the platelet has evolved various mechanisms by which is utilizes getting it inside. It is that important for this virus. This type of virus is not recirculating. In this case, what we observed is that the virus is attached to microparticles that are of platelet origin for that matter. Cindy St. Hilaire:        So really what you're saying, what I'm hearing is the platelet is the superhero of the body. Milka Koupenova:       Definitely. Absolutely. No bias, absolutely. Cindy St. Hilaire:        Unbiasedly, it is a superhero. Well, Dr Cameron and Dr Koupenova, thank you so much not only for this amazing discussion, but for really an elegant, elegant paper that is really bringing to light the complex interaction between SARS-CoV-2 and platelets. So thank you so much for joining me and keep publishing amazing stories like this. Milka Koupenova:       Thank you for having us. Scott Cameron:           Thank you, an honor to be here. Thanks again. Cindy St. Hilaire:        That's it for the highlights from August 20th and September 3rd issues of Circulation Research. Thank you for listening. Please check out the CircRes Facebook page and follow us on Twitter and Instagram with the handle @CircRes and #DiscoverCircRes. Thank you to our guests, Dr Scott Cameron and Dr Milka Koupenova. This podcast is produced by Ashara Ratnayaka, edited by Melissa Stoner, and supported by the editorial team of Circulation Research. Some of the copy text for the highlighted articles is provided by Ruth Williams. I'm your host, Dr Cynthia St. Hilaire, and this is Discover CircRes, your on-the-go source for the most exciting discoveries in basic cardiovascular research. This program is copyright of the American Heart Association, 2021. 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 information, please visit ahajournals.org.  

Hasta una cuarta parte de las formas severas que desarrollan los pacientes con Covid 19 se puede explicar por una anomalía genética o inmunológica. Así lo confirman los estudios llevados a cabo por una colaboración franco-norteamericana y que se basaron en muestras de 400 laboratorios provenientes de 38 países. Los dos estudios se publicaron en la revista Science Immunology y amplían lo que ya se había observado en octubre del 2020. Cada día se confirma más la pista de las anomalías genéticas e inmunológicas para explicar una parte de las formas severas que algunos pacientes desarrollan al contraer la Covid 19. Los equipos del profesor Jean Laurent Casanova en Francia y de Laurent Abel en Estados Unidos, publicaron dos importantes estudios en octubre del 2020, en la revista Science para explicar que del 10 al 15 % de estas formas severas podía tener una explicación relacionada con una proteína, el interferón tipo uno. En octubre, RFI hizo un programa al respecto que puede consultar aquí.  Dos nuevos estudios internacionales coordinados por los mismos laboratorios y publicados ahora en Science Immunology, aportan nuevos hallazgos e incluso podrían explicar entre el 20 y el 25 % de estas formas severas. Por el lado francés, las investigaciones estuvieron a cargo del Instituto Imagine, el cual se encuentra al lado del Hospital Necker para niños enfermos de París. Este instituto Imagine se consagra al estudio de las enfermedades genéticas. El Doctor Paul Bastard, médico pediatra, es estudiante de tesis en el laboratorio de Jean Laurent Casanova y es uno de los autores principales de uno de los dos estudios. Estas dos investigaciones son capitales para comprender mejor la enfermedad de la Covid 19.  Escuche aquí el programa de radio con el doctor Paul Bastard: El Gen TLR7 modificado Con respecto a las anomalías de tipo genético, los investigadores encontraron que al menos del 3 al 4 % de las formas severas tienen un origen genético, relacionado con una anomalía del gen TLR7, fundamental en el mecanismo de la producción del interferón tipo 1 (IFN 1). Este es uno de los estudios publicados. Anomalías de tipo inmune El segundo estudio publicado está relacionado con las anomalías de tipo inmune. Del 10 al 11 % de las formas severas de la Covid 19 se explica por la presencia de “auto anticuerpos” en la sangre que destruyen los interferones tipo 1 bloqueando así su función antiviral. Conforme avanza la edad, más auto anticuerpos en la sangre A fin de comprender mejor la distribución de estos auto anticuerpos en la población general no infectada y si la edad tiene algo que ver, los autores compararon muestras de más de 34 mil individuos sanos, clasificados por sexo y por edad, de diferentes estudios de cohorte del INSERM, del Establecimiento francés de sangre y de Cerba Healthcare y los investigadores hicieron un gran hallazgo: encontraron que la presencia de estos auto anticuerpos es muy rara antes de los 65 años de edad (0.2 al 0.5 %), pero después aumenta considerablemente con la edad, alcanzando hasta el 4% de las personas entre 70 y 79 años y el 7 % entre 80 y 85 años. Esto podría explicar en parte porqué en personas mayores que se contagiaron con el SARS CoV 2, se desarrollan formas graves de la Covid 19, ya que quizás un porcentaje importante de esta población mayor tenía estos auto anticuerpos en su sangre destruyendo los interferones tipo 1. Entrevistado: el médico pediatra Paul Bastard, del Hospital Necker de París (Institute Imagine, especializado en enfermedades genéticas). Sobre el mismo tema: ¿Por qué algunas personas desarrollan casos graves por covid y otras no? Una pista, las anomalías genéticas

In this Buddisode, Dara & Jatin sit down with Adam Fike from Ziaur Rahman's lab at Penn State University. The discussion entails their 2020 publication that teased apart the contribution of Type I and Type II interferons in TLR7-mediated systemic autoimmunity. Check out our memes on Facebook (@antibuddies), Twitter (@antibuddiesP), and Instagram (@AntibuddiesPodcast). Website: Antibuddies – Science Communication & Immunology (Antibuddies.org) Join us on our monthly journal club at our YouTube channel: https://www.youtube.com/channel/UCxyrHotyyY3sSwcp1zigeCw Send us your queries/questions/suggestions at antibuddies1@gmail.com. Article of discussion: Type II but Not Type I IFN Signaling Is Indispensable for TLR7-Promoted Development of Autoreactive B Cells and Systemic Autoimmunity | The Journal of Immunology (jimmunol.org)    

Reviewing an article, a new study that shows the Pfizer vaccine alters innate immunity (which is based on the genome/DNA) and also decreases the ability of white blood cell reports TLR7, TLR8 to fight viral infection, bacteria and fungi which is very similar to the AIDS opportunistic infections that have high mortality rates, for example in india the Black Fungus is now a huge concern for many "COVID" survivors. We also shows a study that proves COVID-19 uses reverse transcriptase to enter the human chromosome, debunking the fact checkers.

Professor Luke O'Neill joins Pat with news and updates from the world of science including Should the whole world move to vaccinating as many as possible with one shot? Cases rising again in India, Airborne pollen and Covid19, TLR7 and risk of severe Covid19.    Listen and subscribe to The Pat Kenny Show on Apple Podcasts, Google Podcasts and Spotify.      Download, listen and subscribe on the Newstalk App.    You can also listen to Newstalk live on newstalk.com or on Alexa, by adding the Newstalk skill and asking: 'Alexa, play Newstalk'.

On this week’s episode, we discuss Taurus’ new TX-22 Competition pistol, Timney’s new competition Glock Trigger, Gerber’s Sedulo knife, and Streamlights new TLR-7 sub weaponlight for mini pistols. For all the show notes and back episodes, head over to firearmsradio.tv/gun-and-gear-review-podcast

On this week’s episode, we discuss Taurus’ new TX-22 Competition pistol, Timney’s new competition Glock Trigger, Gerber’s Sedulo knife, and Streamlights new TLR-7 sub weaponlight for mini pistols. For all the show notes and back episodes, head over to firearmsradio.tv/gun-and-gear-review-podcast

On this week's episode, we discuss Taurus’ new TX-22 Competition pistol, Timney’s new competition Glock Trigger, Gerber’s Sedulo knife, and Streamlights new TLR-7 sub weaponlight for mini pistols. For all the show notes and back episodes, head over to firearmsradio.tv/gun-and-gear-review-podcast

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.11.377713v1?rss=1 Authors: Choudhury, A., Das, N. C., Patra, R., Bhattacharya, M., Mukherjee, S. Abstract: The worldwide outbreak of COVID-19 pandemic caused by SARS-CoV-2 leads to loss of mankind and global economic stability. The continuous spreading of the disease and its pathogenesis takes millions of lives of peoples and the unavailability of appropriate therapeutic strategy makes it much more severe. Toll-like receptors (TLRs) are the crucial mediators and regulators of host immunity. The role of several TLRs in immunomodulation of host by SARS-CoV-2 is recently demonstrated. However, the functionality of human intracellular TLRs including TLR3,7,8 and 9 is still being untested for sensing of viral RNA. This study is hoped to rationalize the comparative binding and sensing of SARS-CoV-2 mRNA towards the intracellular TLRs, considering the solvent-based force-fields operational in the cytosolic aqueous microenvironment that predominantly drive these reactions. Our in-silico study on the binding of all mRNAs with the intracellular TLRs shown that the mRNA of NSP10, S2, and E proteins of SARS-CoV-2 are potent enough to bind with TLR3, TLR9, and TLR7 and trigger downstream cascade reactions, and may be used as an option for validation of therapeutic option and immunomodulation against COVID-19. Copy rights belong to original authors. Visit the link for more info

Show Notes for Episode Fifteen of seX & whY: Sex Differences in Immunology and Drug Therapy Host: Jeannette Wolfe Guests: Evelyne Bischof MD, Associate Professor of Medicine at Shanghai University of Medicine and Health Sciences and internist at University Hospital of Basel Switzerland Sabra Klein, PhD, Professor of Molecular Microbiology and Immunology at Johns Hopkins Bloomberg School of Public Health This podcast focused on sex differences in immunology and pharmacology and its relevance to the Covid-19 pandemic. Key points Males are more likely to be admitted to the ICU and die from COVID-19 compared to females Males and females have differences in both innate and adaptive immunity (which likely are a combo of chromosomal, hormonal and epigentic differences) One difference in Innate immunity (the initial non-specific reaction to a foreign pathogen) is Toll-like receptor 7 (TLR7) This is a major player in the initial physiological response to a foreign pathogen and the gene for it is on the X chromosome. X-lined genes (like Ace-2 which is the receptor which SARS-Cov-2 initially binds to in the body) are interesting because they immediately bring up two considerations.  First, if someone has a specific variant of that gene, it could change their susceptibility to certain pathogens. Males, as they have an XY pair of sex chromosomes, only have one X chromosome and thus could be more adversely impacted than females (XX) who have a second copy of the gene (which may or may not express the same variant)  from their other X chromosome. The second consideration is that in the cells of most females, one of the X chromosomes is automatically turned off (X inactivation). It appears however, that some X-linked immune cells- like TLR7- don't do this, leading to the possibility of increased expression of the gene like getting an “extra dose”. In adaptive immunity (which involved B and T cells), females generally have a greater immunological response to most pathogens. As such, females generally exhibit a more robust immune response to natural infections and vaccinations. The flip side, however, is compared to men, women are also at greater risk for autoimmune diseases and are more likely to get local and systemic reactions after a vaccination. When testing the effectiveness and side effects of SARS-CoV-2 vaccines it would be ideal to consider the variables of biological sex and age. In an influenza study, when women were given a ½ dose of the flu vaccine, they mounted a similar immune response to males who got full dose. If the same held true for developing SARS-Cov2 vaccinations, it could potentially increase the amount of vaccine available (though it is unclear if this is even being considered in early vaccine trials). Aging can also impair the immune response and older adults may require higher doses of booster doses of some vaccines to optimize their immune response The use of Artificial Intelligence in drug development may revolutionize the pharmaceutical research industry by allowing more predictive drug modeling leading to more successful drug development. This could also be used to better identify potentially important biological sex- based pharmacodynamic and pharmacokinetic differences earlier in drug development. Two unexpected findings associated with COVID-19 Males appear to be more vulnerable to cytokine storm (mechanism still not entirely clear may be differences in ACE-2 receptors, or chromosomal/hormonal differences in innate/adaptive immune system) Elderly sick males who survived COVID-19 appear to have significant protective antibody production against SARS-Cov2 References: Bischof E, Wolfe J, Klein S: Clinical trials for Covid-19 should include Sex as a Variable. JCI 2020 Engler R, Nelson M, Klote M, et al. Half- vs Full-Dose Trivalent Inactivated Influenza Vaccine (2004-2005) Age, Dose, and Sex Effects on Immune Responses, JAMA Internal Medicine 2008 Gender and COVID-19 Working Group website Global Health 50/50  global deaths disaggregated by sex Klein S, Pekosz A, Park H. et al.  Sex, age and hospitalization drive antibody responses in a Covid-19 convalescent plasma donor population. JCI 2020 Roberts M, Genway S How Artificial Intelligence is transforming drug design. DDW Souyris M, Cenac C, Azar P, et al. TLR7 Escapes X Chromosome Inactivation in Immune Cells. Autoimmune Disease 2018 Takehiro T, Ellingson M, Wong P et al. Sex Differences in Immune Responses that underlie COVID-19 disease outcomes. Nature 2020 Zucker I, Prendergast B.  Sex differences in pharmacokinetics predict adverse drug reactions in women. Biology of Sex Differences 2020 Special thanks to Doug Deems for help with editing

In our new podcast, we welcome guest Jonathan Deane from GNF to discuss both the difficult and rewarding properties of drug discovery and research. The thoughts and opinions of our guest, Jonathan Deane, are his own personal reflections and do not necessarily reflect the opinions or positions of The Genomics Institute of the Novartis Research Foundation (GNF). Topics The Genomics Institute of the Novartis Research Foundation Jonathan Deane’s TLR7 article and painting The American Association of Immunologists Advocacy Center The Good and Bad of Generic Drugs Pricing Pharmaceuticals, Parts 1 and 2 Giving a Scientific Talk, Parts 1 and 2 Keywords: Jonathan Deane, drug discovery, podcast, BioLegend, GNF, genomics institute of the Novartis research foundation, pharmaceutical, toastmasters, innate immunity, TLR7, clinical, American Association of Immunologists, lupus  

Prof Stefan Endres (Ludwig-Maximilians-Universität, Munich, Germany) talks to ecancertv at the 1st Immunotherapy of Cancer Conference ( ITOC ) in Munich about toll like receptor 7 agonists for cancer immunotherapy. Toll like receptor 7 (TLR7) is from a class of proteins that play a key role in the innate immune system. One approach is to combine TLR7 RNA with a chemical from the triphosphate group, inducing interferon and alpha helping the immune system to fight tumour cells. Dr Endres covers the different approaches for activating the patient's own immune system to fight cancer.

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.

The TLR7 agonist imiquimod has been used successfully as adjuvant for skin treatment of virus-associated warts and basal cell carcinoma. The effects of skin TLR7 triggering on respiratory leukocyte populations are unknown. In a placebo-controlled experimental animal study we have used multicolour flow cytometry to systematically analyze the modulation of respiratory leukocyte subsets after skin administration of imiquimod. Compared to placebo, skin administration of imiquimod significantly increased respiratory dendritic cells (DC) and natural killer cells, whereas total respiratory leukocyte, alveolar macrophages, classical CD4+ T helper and CD8+ T killer cell numbers were not or only moderately affected. DC subpopulation analyses revealed that elevation of respiratory DC was caused by an increase of respiratory monocytic DC and CD11b(hi) DC subsets. Lymphocyte subpopulation analyses indicated a marked elevation of respiratory natural killer cells and a significant reduction of B lymphocytes. Analysis of cytokine responses of respiratory leukocytes after stimulation with Klebsiella pneumonia indicated reduced IFN-γ and TNF-α expression and increased IL-10 and IL-12p70 production after 7 day low dose skin TLR7 triggering. Additionally, respiratory NK cytotoxic activity was increased after 7d skin TLR7 triggering. In contrast, lung histology and bronchoalveolar cell counts were not affected suggesting that skin TLR7 stimulation modulated respiratory leukocyte composition without inducing overt pulmonary inflammation. These data suggest the possibility to modulate respiratory leukocyte composition and respiratory cytokine responses against pathogens like Klebsiella pneumonia through skin administration of a clinically approved TLR7 ligand. Skin administration of synthetic TLR7 ligands may represent a novel, noninvasive means to modulate respiratory immunity.

Vincent, Alan, and Rich are very enthusiastic about two studies that show how gut bacteria help viral invaders.

Conventional cancer therapies like surgery, radiation and chemotherapy help to eliminate primary tumor masses but often fail to eradicate disseminated tumor cells. However, it is such residual tumor cells that frequently underlie metastasis and relapse. Major obstacles for targeting such cells are wide spread dissemination and long-term persistence in niches that are difficult to reach. For example, many patients with acute myeloid leukemia (AML) show persistence of leukemia after chemotherapy – so-called minimal residual disease (MRD) – which confers a life-threatening risk for relapse in over 70% of patients. Arming the immune system to attack residual tumor cells has high therapeutic potential since immune cells can patrol the body to find and destroy residual tumor cells. Therapeutic approaches using the immune system - so-called immunotherapies - can take several forms. My project concentrated on preclinical studies of two strategies: 1) use of dendritic cells (DC) for therapeutic vaccination and 2) adoptive T cell therapy with lymphocytes expressing transgenic T cell receptors (TCR) specific for tumor-associated antigens (TAA). In therapeutic vaccination a highly potent vaccine is needed to induce a valid immune response in patients with cancer. Effective antitumor immunity requires mobilization of IFN-γ-producing CD4+ T cells (Th1 cells) and lymphocytes with cytotoxic function, including cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. In my studies, high potency vaccines were developed using mature DC generated in 3 days (3d-mDC) that were stimulated with synthetic Toll-like receptor TLR3 and/or TLR7/8 agonists. This TLR stimulation mimics DC interaction with viruses and causes mDC to secrete the bioactive form of IL-12, supporting induction of effector cells. Characterization in vitro showed that TLR-activated 3d-mDC were superior to conventional 7d-mDC in capacity to induce Th1 cells as well as CTL. A humanized mouse model was established to verify these observations in vivo. NOD/scid IL2Rgnull mice, lacking murine T, B and NK cells, were reconstituted with human peripheral mononuclear cells and vaccinated with 3d-mDC, stimulated or not with TLR agonists, and conventional 7d-mDC. Induction of CTL was quantified ex vivo using splenocyte populations containing human lymphocytes. The in vivo results were concordant with in vitro observations, demonstrating the superior capacity of 3d-mDC that were stimulated with TLR agonists to induce CTL. Adoptive T cell therapy using TCR-modified lymphocytes represents a second powerful way to provide patients with specific antitumor immunity. Here previously isolated TCR gene sequences are introduced into activated patient-derived lymphocytes, assigning them new antigen specificities. First, T cells must be isolated with TAA specificities that express high-affinity TCR which effectively recognize tumor cells. It was contended that T cell stimulation using peptide-epitopes from TAA presented on foreign MHC would allow isolation of high-affinity TCR, since these T cells had not yet undergone negative selection in the thymus. This contention was proved in individual experiments, as described in this thesis, for the antigens tyrosinase, survivin and HMMR (hyaluronan-mediated motility receptor). Since survivin and HMMR are broadly expressed in AML, TCR specific for these TAA were isolated and subsequently transferred into recipient lymphocytes. Expression of survivin-specific TCR resulted in MHC-restricted death of transduced lymphocytes due to their elevated survivin expression after activation. This precludes use of survivin-specific TCR for therapy of AML. In contrast, transfer of an HMMR-specific TCR yielded effector lymphocytes that effectively killed AML cells in vitro. The behavior in vivo of TCR transduced lymphocytes is crucial for therapeutic outcome. To explore this capacity a xenograft mouse model was established using solid and disseminated human tumor cells injected into NOD/scid IL2Rgnull mice. Adoptive transfer of lymphocytes expressing an HMMR-specific TCR into tumor-bearing mice resulted in significant retardation of tumor outgrowth. Adoptive transfer of memory-like lymphocytes with higher proliferative potential and prolonged in vivo survival may also affect tumor growth. Analyses in vivo and in vitro showed that IL-15-induced effector memory T cells conferred the most potent antitumor immunity. In summary, this work provides evidence for potent in vivo antitumor effects by either using DC-based vaccines or adoptive transfer of TCR transduced lymphocytes, opening application of both strategies for immunotherapy of cancer.

Background: Active dendritic cell (DC) immunization protocols are rapidly gaining interest as therapeutic options in patients with acute myeloid leukemia (AML). Here we present for the first time a GMP-compliant 3-day protocol for generation of monocyte-derived DCs using different synthetic Toll-like receptor (TLR) agonists in intensively pretreated patients with AML. Methods: Four different maturation cocktails were compared for their impact on cell recovery, phenotype, cytokine secretion, migration, and lymphocyte activation in 20 AML patients and 25 healthy controls. Results: Maturation cocktails containing the TLR7/8 agonists R848 or CL075, with and without the addition of the TLR3 agonist poly(I:C), induced DCs that had a positive costimulatory profile, secreted high levels of IL-12(p70), showed chemotaxis to CCR7 ligands, had the ability to activate NK cells, and efficiently stimulated antigen-specific CD8(+) T cells. Conclusions: Our results demonstrate that this approach translates into biologically improved DCs, not only in healthy controls but also in AML patients. This data supports the clinical application of TLR-matured DCs in patients with AML for activation of innate and adaptive immune responses.

Thu, 14 Oct 2010 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/12248/ https://edoc.ub.uni-muenchen.de/12248/1/Lanz_Anna-Lisa.pdf Lanz, Anna-Lisa

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.