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Archive for the ‘T-cell response to SARS-CoV-2 infection’ Category


Ramatroban, a Thromboxane A2/TPr and PGD2/DPr2 receptor antagonist for Acute and Long haul COVID-19

Author: Ajay Gupta, MD

From: “Gupta, Ajay” <ajayg1@hs.uci.edu>
Date: Wednesday, July 7, 2021 at 1:10 PM
To: Aviva Lev-Ari <AvivaLev-Ari@alum.berkeley.edu>
Cc: “Dr. Saul Yedgar” <saulye@ekmd.huji.ac.il>
Subject: Ramatroban, a Thromboxane A2/TPr and PGD2/DPr2 receptor antagonist for Acute and Long haul COVID-19

While corticosteroids may have a role in about 5% of hospitalized patients who have the cytokine storm, currently there is no effective treatment for mild or moderate COVID and long haul COVID. Massive increase in respiratory and plasma thromboxane A2 (TxA2) plays a key role in thromboinflammation and microvascular thrombosis, while an increase in respiratory and plasma PGD2 potentially suppresses innate interferon response, and acquired Th1 anti-viral response, while promoting a maladaptive type 2, anti-helminthic like immune response. Ramatroban is a potent dual receptor antagonist of Thromboxane A2/TPr and PGD2/DPr2 that has been used in Japan for the treatment of allergic rhinitis for past 20 years (Baynas®, Bayer Japan). We first disclosed use of ramatroban for COVID in a provisional patent application filed on 31st March, 2020; followed by the publication Gupta et al, J Mol Genet Med, 2020

Several experts, as outlined below in yellow highlighted text, have supported the idea of using ramatroban as an anti-thrombotic and immunomodulator in COVID-19.

1.     Prof. Louis Flamand, Nicolas Flamand, Eric Boilard Laval Univ. Quebec, Canada: There is a lipid-mediator storm in COVID-19 characterized by massive increases in thromboxane A2 and PGD2 in the lungs and plasma.  “Blocking the deleterious effects of             PGD2 and TxA2 with the dual DPr2/TPr antagonist Ramatroban might be beneficial in COVID-19 Archambault et al, FASEB, June 2021, doi: https://doi.org/10.1096/fj.202100540R

2. Prof. Garret A FitzGerald, Univ. Of Pennsylvania, Member National Academy of Sciences.https://en.wikipedia.org/wiki/Garret_A._FitzGerald “In the current pandemic there may be utility in targeting eicosanoids with existing drugs.  These approaches would likely be most effective early in the disease before the development of ARDS, where cytokines and chemokines dominate. Dexamethasone limits COX-2 expression and might diminish COVID-19 severity and mortality at least in part, by diminishing COX metabolites… Dexamethasone might improve severe COVID-19 by diminishing the prostaglandins / thromboxane storm in the lungs”. “Treatment with a PGD2/DPr2 inhibitor decreased viral load and improved morbidity by upregulating IFN-lambda expression. …..  Antagonism of the thromboxane receptor (TPr) prevents ARDS…. Early administration of well-tolerated TPr antagonists may limit progress to severe COVID-19 (Theken and FitzGerald, Science, 2021)

4.     Prof. Simon Phipps, Univ. of Queensland, Brisbane Australia “It has been hypothesized that DP2 antagonists be repurposed as a novel immunotherapy for the treatment of COVID-19, and this may be appropriate in mild to moderate cases where Th1 immunity is impaired.” (Ullah et al, Mucosal Immunology, 2021)

5.     Prof. Bruce D. Hammock, Distinguished Professor, Univ of California DavisMember US National Academy of Sciences and National Academy of Inventors; April 25, 2021. https://www.entsoc.org/fellows/hammock “I find your idea of blocking specific thromboxane receptors in preventing or reducing some of the devastating co-morbidity of COVID-19 very compelling. … A DPr2 receptor blocker is conceptually attractive in offering the potential of effective therapy and low risk due to a high therapeutic index.” E mail dated April 25, 2021.  (https://ajp.amjpathol.org/action/showPdf?pii=S0002-9440%2820%2930332-1    and http://ucanr.edu/sites/hammocklab/files/328012.pdf)

6. Ann E Eakin, PhD, Senior Scientific Officer, NIH-NIAID “very compelling data supporting potential benefits of ramatroban in both reducing viral load as well as modulating host responses” E Mail dated Nov 20, 2020

7. Prof. James Ritter, MA, DPhil, FRCP, FMedSci, Hon FBPhS https://www.trinhall.cam.ac.uk/contact-us/contact-directory/fellows-and-academics-directory/james-ritter/ “Very impressive, and fascinating” referring to ramatroban for COVID-19 in an e-mail dated Dec 21, 2020

Ramatroban is expected to reduce lung fibrosis in COVID-19 and therefore diminish clinical manifestations of Long haul COVID. Pang et al, 2021 “examined the effect of Ramatroban, a clinical antagonist of both PGD2 and TXA2 receptors, on treating silicosis using a mouse model. The results showed that Ramatroban significantly alleviated silica-induced pulmonary inflammation, fibrosis, and cardiopulmonary dysfunction compared with the control group.” https://www.thno.org/v11p2381.htm

Unfortunately, the animal models of COVID-19 are harsh, lack microvascular thrombosis and immune perturbations characteristic of human disease. These models may be good for testing antivirals but not for testing immunomodulators or anti-thrombotics. There is highly positive anecdotal experience with use of ramatroban in moderately severe COVID-19 (https://www.researchsquare.com/article/rs-474882/v1

Additionally, Ramatroban holds great promise in sickle cell disease, cardiovascular disease https://doi.org/10.1111/j.1527-3466.2004.tb00132.x, and community acquired pneumonia.

Best regards,

Ajay

Ajay Gupta, M.B.,B.S., M.D.

Clinical Professor,

Division of Nephrology, Hypertension and Kidney Transplantation

University of California Irvine  

President & CSO, KARE Biosciences (www.karebio.com)

E-mail:     ajayg1@hs.uci.edu

Cell:         1 (562) 412-6259

Office:     1 (562) 419-7029

Please see some of our recent publications in the COVID area.  

https://assets.researchsquare.com/files/rs-474882/v1/6d209040-e94b-4adf-80a9-3a9eddf93def.pdf?c=1619795476

https://www.uni-muenster.de/Ejournals/index.php/fnp/article/view/3395

https://www.tandfonline.com/doi/full/10.1080/13543784.2021.1950687

https://www.amjmed.com/article/S0002-9343(20)30872-X/fulltext

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Covid-19 and its implications on pregnancy

Reporter and Curator: Mr. Srinjoy Chakraborty (Junior Research Felllow) and Dr. Sudipta Saha, Ph.D.

Coronavirus disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emerged as a serious global health issue with high transmission rates affecting millions of people worldwide. The SARS-CoV-2 is known to damage cells in the respiratory system, thus causing viral pneumonia. The novel SARS-CoV-2 is a close relative to the previously identified severe acute respiratory syndrome-coronavirus (SARS-CoV) and Middle East respiratory syndrome-coronavirus (MERS-CoV) which affected several people in 2002 and 2012, respectively. Ever since the outbreak of covid-19, several reports have poured in about the impact of Covid-19 on pregnancy. A few studies have highlighted the impact of the viral infection in pregnant women and how they are more susceptible to the infection because of the various physiological changes of the cardiopulmonary and immune systems during pregnancy. It is known that SARS-CoV and MERS-CoV diseases have influenced the fatality rate among pregnant women. However, there are limited studies on the impact of the novel corona virus on the course and outcome of pregnancy.

Figure: commonly observed clinical symptoms of COVID-19 in the general population: Fever and cough, along with dyspnoea, diarrhoea, and malaise are the most commonly observed symptoms in pregnant women, which is similar to that observed in the normal population.

The WHO and the Indian Council of Medical Research (ICMR) have proposed detailed guidelines for treating pregnant women; these guidelines must be strictly followed by the pregnant individual and their families. According to the guidelines issued by the ICMR, the risk of pregnant women contracting the virus to that of the general population. However, the immune system and the body’s response to a viral infection is altered during pregnancy. This may result in the manifestation of more severe symptoms. The ICMR guidelines also state that the reported cases of COVID-19 pneumonia in pregnancy are milder and with good recovery. However, by observing the trends of the other coronavirus infection (SARS, MERS), the risks to the mother appear to increase in particular during the last trimester of pregnancy. Cases of preterm birth in women with COVID-19 have been mentioned in a few case report, but it is unclear whether the preterm birth was always iatrogenic, or whether some were spontaneous. Pregnant women with heart disease are at highest risk of acquiring the infection, which is similar to that observed in the normal population. Most importantly, the ICMR guidelines highlights the impact of the coronavirus epidemic on the mental health of pregnant women. It mentions that the since the pandemic has begun, there has been an increase in the risk of perinatal anxiety and depression, as well as domestic violence. It is critically important that support for women and families is strengthened as far as possible; that women are asked about mental health at every contact.

With the available literature available on the impact of SARS and MERS on reproductive outcome, it has been mentioned that SARS infection did increase the risk of miscarriage, preterm birth and, intrauterine foetal growth restriction. However, the same has not been demonstrated in early reports from COVID-19 infection in pregnancy. According to a study that included 8200 participants conducted by the centre for disease control and prevention, pregnant women may be at a higher risk of acquiring severe infection and need for ICU admissions as compared to their non-pregnant counterparts. However, a detailed and thorough study involving a larger proportion of the population is needed today.

References:

https://www.news-medical.net/news/20210614/COVID-19-in-pregnancy-could-be-less-severe-than-previously-thought-A-Danish-case-study.aspx

https://obgyn.onlinelibrary.wiley.com/doi/10.1111/jog.14696

https://www.nature.com/articles/s41577-021-00525-y

https://www.tandfonline.com/doi/full/10.1080/14767058.2020.1759541

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/special-populations/pregnancy-data-on-covid-19/what-cdc-is-doing.html

https://economictimes.indiatimes.com/news/india/why-is-covid-19-killing-so-many-pregnant-women-in-india/articleshow/82902194.cms?from=mdr

https://content.iospress.com/download/international-journal-of-risk-and-safety-in-medicine/jrs200060?id=international-journal-of-risk-and-safety-in-medicine%2Fjrs200060

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Nir Hacohen and Marcia Goldberg, Researchers at MGH and the Broad Institute identify protein “signature” of severe COVID-19

Curator and Reporter: Aviva Lev-Ari, PhD, RN

Longitudinal proteomic analysis of plasma from patients with severe COVID-19 reveal patient survival-associated signatures, tissue-specific cell death, and cell-cell interactions

Open AccessPublished:April 30, 2021DOI:https://doi.org/10.1016/j.xcrm.2021.100287

Highlights

  • 16% of COVID-19 patients display an atypical low-inflammatory plasma proteome
  • Severe COVID-19 is associated with heterogeneous plasma proteomic responses
  • Death of virus-infected lung epithelial cells is a key feature of severe disease
  • Lung monocyte/macrophages drive T cell activation, together promoting epithelial damage

Summary

Mechanisms underlying severe COVID-19 disease remain poorly understood. We analyze several thousand plasma proteins longitudinally in 306 COVID-19 patients and 78 symptomatic controls, uncovering immune and non-immune proteins linked to COVID-19. Deconvolution of our plasma proteome data using published scRNAseq datasets reveals contributions from circulating immune and tissue cells. Sixteen percent of patients display reduced inflammation yet comparably poor outcomes. Comparison of patients who died to severely ill survivors identifies dynamic immune cell-derived and tissue-associated proteins associated with survival, including exocrine pancreatic proteases. Using derived tissue-specific and cell type-specific intracellular death signatures, cellular ACE2 expression, and our data, we infer whether organ damage resulted from direct or indirect effects of infection. We propose a model in which interactions among myeloid, epithelial, and T cells drive tissue damage. These datasets provide important insights and a rich resource for analysis of mechanisms of severe COVID-19 disease.

Graphical Abstract

Figure thumbnail fx1

Image Source: DOI: https://doi.org/10.1016/j.xcrm.2021.100287

https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(21)00115-4

The quest to identify mechanisms that might be contributing to death in COVID-19: Why do some patients die from this disease, while others — who appear to be just as ill do not?

Researchers at Massachusetts General Hospital (MGH) and the Broad Institute of MIT and Harvard have identified the protein “signature” of severe COVID-19

Interest was to develop methods for studying human immune responses to infections, which they had applied to the condition known as bacterial sepsis. The three agreed to tackle this new problem with the goal of understanding how the human immune system responds to SARS-CoV-2, the novel pathogen that causes COVID-19.

How scientists launched a study in days to probe COVID-19’s unpredictability

Collecting these specimens required a large team of collaborators from many departments, which worked overtime for five weeks to amass blood samples from 306 patients who tested positive for COVID-19, as well as from 78 patients with similar symptoms who tested negative for the coronavirus.

Alexandra-Chloé Villani

Credit : Alexandra-Chloé VillaniResearch associates at Mass General who worked countless hours to process blood samples for the COVID Acute Cohort Study (from left to right: Anna Gonye, Irena Gushterova, and Tom Lasalle)By Leah Eisenstadt

https://www.broadinstitute.org/news/how-scientists-launched-study-days-probe-covid-19%E2%80%99s-unpredictability

As the COVID-19 surge began in March, Mass General and Broad researchers worked around the clock to begin learning why some patients fare worse with the disease than others

Protein signatures in the blood

https://www.broadinstitute.org/news/researchers-identify-protein-%E2%80%9Csignature%E2%80%9D-severe-covid-19

The study found that most patients with COVID-19 have a consistent protein signature, regardless of disease severity; as would be expected, their bodies mount an immune response by producing proteins that attack the virus. “But we also found a small subset of patients with the disease who did not demonstrate the pro-inflammatory response that is typical of other COVID-19 patients,” Filbin said, yet these patients were just as likely as others to have severe disease. Filbin, who is also an assistant professor of emergency medicine at Harvard Medical School (HMS), noted that patients in this subset tended to be older people with chronic diseases, who likely had weakened immune systems.

Among other revelations, this showed that the most prevalent severity-associated protein, a pro-inflammatory protein called interleukin-6 (IL-6) rose steadily in patients who died, while it rose and then dropped in those with severe disease who survived. Early attempts by other groups to treat COVID-19 patients experiencing acute respiratory distress with drugs that block IL-6 were disappointing, though more recent studies show promise in combining these medications with the steroid dexamethasone.

Hacohen, who is a professor of medicine at HMS and director of the Broad’s Cell Circuits Program:

“You can ask which of the many thousands of proteins that are circulating in your blood are associated with the actual outcome,” he said, “and whether there is a set of proteins that tell us something.”

Goldberg, who is a professor of emergency medicine at HMS:

They are highly likely to be useful in figuring out some of the underlying mechanisms that lead to severe disease and death in COVID-19,” she said, noting her gratitude to the patients involved in the study. Their samples are already being used to study other aspects of COVID-19, such as identifying the qualities of antibodies that patients form against the virus.

SOURCES

Original Research

Filbin MR, Mehta A, et al. Longitudinal proteomic analysis of plasma from patients with severe COVID-19 reveal patient survival-associated signatures, tissue-specific cell death, and cell-cell interactionsCell Reports Medicine. Online April 30, 2021. DOI: 10.1016/j.xcrm.2021.100287.

Adapted from a press release originally issued by Massachusetts General Hospital.

https://www.broadinstitute.org/news/researchers-identify-protein-%E2%80%9Csignature%E2%80%9D-severe-covid-19

https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(21)00115-4

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Thriving Vaccines and Research: Weizmann Institute Coronavirus Research Development

Reporter: Amandeep Kaur, B.Sc., M.Sc.

In early February, Prof. Eran Segal updated in one of his tweets and mentioned that “We say with caution, the magic has started.”

The article reported that this statement by Prof. Segal was due to decreasing cases of COVID-19, severe infection cases and hospitalization of patients by rapid vaccination process throughout Israel. Prof. Segal emphasizes in another tweet to remain cautious over the country and informed that there is a long way to cover and searching for scientific solutions.

A daylong webinar entitled “COVID-19: The epidemic that rattles the world” was a great initiative by Weizmann Institute to share their scientific knowledge about the infection among the Israeli institutions and scientists. Prof. Gideon Schreiber and Dr. Ron Diskin organized the event with the support of the Weizmann Coronavirus Response Fund and Israel Society for Biochemistry and Molecular Biology. The speakers were invited from the Hebrew University of Jerusalem, Tel-Aviv University, the Israel Institute for Biological Research (IIBR), and Kaplan Medical Center who addressed the molecular structure and infection biology of the virus, treatments and medications for COVID-19, and the positive and negative effect of the pandemic.

The article reported that with the emergence of pandemic, the scientists at Weizmann started more than 60 projects to explore the virus from different range of perspectives. With the help of funds raised by communities worldwide for the Weizmann Coronavirus Response Fund supported scientists and investigators to elucidate the chemistry, physics and biology behind SARS-CoV-2 infection.

Prof. Avi Levy, the coordinator of the Weizmann Institute’s coronavirus research efforts, mentioned “The vaccines are here, and they will drastically reduce infection rates. But the coronavirus can mutate, and there are many similar infectious diseases out there to be dealt with. All of this research is critical to understanding all sorts of viruses and to preempting any future pandemics.”

The following are few important projects with recent updates reported in the article.

Mapping a hijacker’s methods

Dr. Noam Stern-Ginossar studied the virus invading strategies into the healthy cells and hijack the cell’s systems to divide and reproduce. The article reported that viruses take over the genetic translation system and mainly the ribosomes to produce viral proteins. Dr. Noam used a novel approach known as ‘ribosome profiling’ as her research objective and create a map to locate the translational events taking place inside the viral genome, which further maps the full repertoire of viral proteins produced inside the host.

She and her team members grouped together with the Weizmann’s de Botton Institute and researchers at IIBR for Protein Profiling and understanding the hijacking instructions of coronavirus and developing tools for treatment and therapies. Scientists generated a high-resolution map of the coding regions in the SARS-CoV-2 genome using ribosome-profiling techniques, which allowed researchers to quantify the expression of vital zones along the virus genome that regulates the translation of viral proteins. The study published in Nature in January, explains the hijacking process and reported that virus produces more instruction in the form of viral mRNA than the host and thus dominates the translation process of the host cell. Researchers also clarified that it is the misconception that virus forced the host cell to translate its viral mRNA more efficiently than the host’s own translation, rather high level of viral translation instructions causes hijacking. This study provides valuable insights for the development of effective vaccines and drugs against the COVID-19 infection.

Like chutzpah, some things don’t translate

Prof. Igor Ulitsky and his team worked on untranslated region of viral genome. The article reported that “Not all the parts of viral transcript is translated into protein- rather play some important role in protein production and infection which is unknown.” This region may affect the molecular environment of the translated zones. The Ulitsky group researched to characterize that how the genetic sequence of regions that do not translate into proteins directly or indirectly affect the stability and efficiency of the translating sequences.

Initially, scientists created the library of about 6,000 regions of untranslated sequences to further study their functions. In collaboration with Dr. Noam Stern-Ginossar’s lab, the researchers of Ulitsky’s team worked on Nsp1 protein and focused on the mechanism that how such regions affect the Nsp1 protein production which in turn enhances the virulence. The researchers generated a new alternative and more authentic protocol after solving some technical difficulties which included infecting cells with variants from initial library. Within few months, the researchers are expecting to obtain a more detailed map of how the stability of Nsp1 protein production is getting affected by specific sequences of the untranslated regions.

The landscape of elimination

The article reported that the body’s immune system consists of two main factors- HLA (Human Leukocyte antigen) molecules and T cells for identifying and fighting infections. HLA molecules are protein molecules present on the cell surface and bring fragments of peptide to the surface from inside the infected cell. These peptide fragments are recognized and destroyed by the T cells of the immune system. Samuels’ group tried to find out the answer to the question that how does the body’s surveillance system recognizes the appropriate peptide derived from virus and destroy it. They isolated and analyzed the ‘HLA peptidome’- the complete set of peptides bound to the HLA proteins from inside the SARS-CoV-2 infected cells.

After the analysis of infected cells, they found 26 class-I and 36 class-II HLA peptides, which are present in 99% of the population around the world. Two peptides from HLA class-I were commonly present on the cell surface and two other peptides were derived from coronavirus rare proteins- which mean that these specific coronavirus peptides were marked for easy detection. Among the identified peptides, two peptides were novel discoveries and seven others were shown to induce an immune response earlier. These results from the study will help to develop new vaccines against new coronavirus mutation variants.

Gearing up ‘chain terminators’ to battle the coronavirus

Prof. Rotem Sorek and his lab discovered a family of enzymes within bacteria that produce novel antiviral molecules. These small molecules manufactured by bacteria act as ‘chain terminators’ to fight against the virus invading the bacteria. The study published in Nature in January which reported that these molecules cause a chemical reaction that halts the virus’s replication ability. These new molecules are modified derivates of nucleotide which integrates at the molecular level in the virus and obstruct the works.

Prof. Sorek and his group hypothesize that these new particles could serve as a potential antiviral drug based on the mechanism of chain termination utilized in antiviral drugs used recently in the clinical treatments. Yeda Research and Development has certified these small novel molecules to a company for testing its antiviral mechanism against SARS-CoV-2 infection. Such novel discoveries provide evidences that bacterial immune system is a potential repository of many natural antiviral particles.

Resolving borderline diagnoses

Currently, Real-time Polymerase chain reaction (RT-PCR) is the only choice and extensively used for diagnosis of COVID-19 patients around the globe. Beside its benefits, there are problems associated with RT-PCR, false negative and false positive results and its limitation in detecting new mutations in the virus and emerging variants in the population worldwide. Prof. Eran Elinavs’ lab and Prof. Ido Amits’ lab are working collaboratively to develop a massively parallel, next-generation sequencing technique that tests more effectively and precisely as compared to RT-PCR. This technique can characterize the emerging mutations in SARS-CoV-2, co-occurring viral, bacterial and fungal infections and response patterns in human.

The scientists identified viral variants and distinctive host signatures that help to differentiate infected individuals from non-infected individuals and patients with mild symptoms and severe symptoms.

In Hadassah-Hebrew University Medical Center, Profs. Elinav and Amit are performing trails of the pipeline to test the accuracy in borderline cases, where RT-PCR shows ambiguous or incorrect results. For proper diagnosis and patient stratification, researchers calibrated their severity-prediction matrix. Collectively, scientists are putting efforts to develop a reliable system that resolves borderline cases of RT-PCR and identify new virus variants with known and new mutations, and uses data from human host to classify patients who are needed of close observation and extensive treatment from those who have mild complications and can be managed conservatively.

Moon shot consortium refining drug options

The ‘Moon shot’ consortium was launched almost a year ago with an initiative to develop a novel antiviral drug against SARS-CoV-2 and was led by Dr. Nir London of the Department of Chemical and Structural Biology at Weizmann, Prof. Frank von Delft of Oxford University and the UK’s Diamond Light Source synchroton facility.

To advance the series of novel molecules from conception to evidence of antiviral activity, the scientists have gathered support, guidance, expertise and resources from researchers around the world within a year. The article reported that researchers have built an alternative template for drug-discovery, full transparency process, which avoids the hindrance of intellectual property and red tape.

The new molecules discovered by scientists inhibit a protease, a SARS-CoV-2 protein playing important role in virus replication. The team collaborated with the Israel Institute of Biological Research and other several labs across the globe to demonstrate the efficacy of molecules not only in-vitro as well as in analysis against live virus.

Further research is performed including assaying of safety and efficacy of these potential drugs in living models. The first trial on mice has been started in March. Beside this, additional drugs are optimized and nominated for preclinical testing as candidate drug.

Source: https://www.weizmann.ac.il/WeizmannCompass/sections/features/the-vaccines-are-here-and-research-abounds

Other related articles were published in this Open Access Online Scientific Journal, including the following:

Identification of Novel genes in human that fight COVID-19 infection

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

https://pharmaceuticalintelligence.com/2021/04/19/identification-of-novel-genes-in-human-that-fight-covid-19-infection/

Fighting Chaos with Care, community trust, engagement must be cornerstones of pandemic response

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

https://pharmaceuticalintelligence.com/2021/04/13/fighting-chaos-with-care/

T cells recognize recent SARS-CoV-2 variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/03/30/t-cells-recognize-recent-sars-cov-2-variants/

Need for Global Response to SARS-CoV-2 Viral Variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/02/12/need-for-global-response-to-sars-cov-2-viral-variants/

Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells

Reporter: Adina Hazan, PhD

https://pharmaceuticalintelligence.com/2020/12/28/mechanistic-link-between-sars-cov-2-infection-and-increased-risk-of-stroke-using-3d-printed-models-and-human-endothelial-cells/

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Identification of Novel genes in human that fight COVID-19 infection

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

Scientists have recognized human genes that fight against the SARS-CoV-2 viral infection. The information about genes and their function can help to control infection and aids the understanding of crucial factors that causes severe infection. These novel genes are related to interferons, the frontline fighter in our body’s defense system and provide options for therapeutic strategies.

The research was published in the journal Molecular Cell.

Sumit K. Chanda, Ph.D., professor and director of the Immunity and Pathogenesis Program at Sanford Burnham Prebys reported in the article that they focused on better understanding of the cellular response and downstream mechanism in cells to SARS-CoV-2, including the factors which causes strong or weak response to viral infection. He is the lead author of the study and explained that in this study they have gained new insights into how the human cells are exploited by invading virus and are still working towards finding any weak point of virus to develop new antivirals against SARS-CoV-2.

With the surge of pandemic, researchers and scientists found that in severe cases of COVID-19, the response of interferons to SARS-CoV-2 viral infection is low. This information led Chanda and other collaborators to search for interferon-stimulated genes (ISGs), are genes in human which are triggered by interferons and play important role in confining COVID-19 infection by controlling their viral replication in host.

The investigators have developed laboratory experiments to identify ISGs based on the previous knowledge gathered by the outbreak of SARS-CoV-1 from 2002-2004 which was similar to COVID-19 pandemic caused by SARS-CoV-2 virus.

The article reports that Chanda mentioned “we found that 65 ISGs controlled SAR-CoV-2 infection, including some that inhibited the virus’ ability to enter cells, some that suppressed manufacture of the RNA that is the virus’s lifeblood, and a cluster of genes that inhibited assembly of the virus.” They also found an interesting fact about ISGs that some of these genes revealed control over unrelated viruses, such as HIV, West Nile and seasonal flu.

Laura Martin-Sancho, Ph.D., a senior postdoctoral associate in the Chanda lab and first author of the study reported in the article that they identified 8 different ISGs that blocked the replication of both SARS-CoV-1 and CoV-2 in the subcellular compartments responsible for packaging of proteins, which provide option to exploit these vulnerable sites to restrict infection. They are further investigating whether the genetic variability within the ISGs is associated with COVID-19 severity.

The next step for researchers will be investigating and observing the biology of variants of SARS-CoV-2 that are evolving and affecting vaccine efficacy. Martin-Sancho mentioned that their lab has already started gathering all the possible variants for further investigation.

“It’s vitally important that we don’t take our foot off the pedal of basic research efforts now that vaccines are helping control the pandemic,” reported in the article by Chanda.

“We’ve come so far so fast because of investment in fundamental research at Sanford Burnham Prebys and elsewhere, and our continued efforts will be especially important when, not if, another viral outbreak occurs,” concluded Chanda.

Source: https://medicalxpress.com/news/2021-04-covid-scientists-human-genes-infection.html

Reference: Laura Martin-Sancho et al. Functional Landscape of SARS-CoV-2 Cellular Restriction, Molecular Cell (2021). DOI: 10.1016/j.molcel.2021.04.008

Other related articles were published in this Open Access Online Scientific Journal, including the following:

Fighting Chaos with Care, community trust, engagement must be cornerstones of pandemic response

Reporter: Amandeep Kaur

https://pharmaceuticalintelligence.com/2021/04/13/fighting-chaos-with-care/

Mechanism of Thrombosis with AstraZeneca and J & J Vaccines: Expert Opinion by Kate Chander Chiang & Ajay Gupta, MD

Reporter & Curator: Dr. Ajay Gupta, MD

https://pharmaceuticalintelligence.com/2021/04/14/mechanism-of-thrombosis-with-astrazeneca-and-j-j-vaccines-expert-opinion-by-kate-chander-chiang-ajay-gupta-md/

T cells recognize recent SARS-CoV-2 variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/03/30/t-cells-recognize-recent-sars-cov-2-variants/

Need for Global Response to SARS-CoV-2 Viral Variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/02/12/need-for-global-response-to-sars-cov-2-viral-variants/

Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells

Reporter: Adina Hazan, PhD

https://pharmaceuticalintelligence.com/2020/12/28/mechanistic-link-between-sars-cov-2-infection-and-increased-risk-of-stroke-using-3d-printed-models-and-human-endothelial-cells/

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COVID-19 Sequel: Neurological Impact of Social isolation been linked to poorer physical and mental health

Reporter: Aviva Lev-Ari, PhD, RN

UPDATED on 4/13/2021

Toward Understanding COVID-19 Recovery: National Institutes of Health Workshop on Postacute COVID-19

 

Abstract

Over the past year, the SARS-CoV-2 pandemic has swept the globe, resulting in an enormous worldwide burden of infection and mortality. However, the additional toll resulting from long-term consequences of the pandemic has yet to be tallied. Heterogeneous disease manifestations and syndromes are now recognized among some persons after their initial recovery from SARS-CoV-2 infection, representing in the broadest sense a failure to return to a baseline state of health after acute SARS-CoV-2 infection. On 3 to 4 December 2020, the National Institute of Allergy and Infectious Diseases, in collaboration with other Institutes and Centers of the National Institutes of Health, convened a virtual workshop to summarize existing knowledge on postacute COVID-19 and to identify key knowledge gaps regarding this condition.

Over the past year, the SARS-CoV-2 pandemic has swept the globe, resulting in more than 113 million persons infected and 2.5 million deaths (1). However, the additional toll resulting from long-term consequences of the pandemic has yet to be tallied. Heterogeneous disease manifestations and syndromes are now recognized among some persons after their initial recovery from SARS-CoV-2 infection. Although a standardized case definition does not yet exist for these manifestations, in the broadest sense they represent a failure to return to a baseline state of health after acute SARS-CoV-2 infection. The various terms used to describe this condition have included postacute (or late) sequelae of COVID-19, post-COVID condition or syndrome, long COVID, and long-haul COVID. In this article, we use the general umbrella term of “postacute COVID-19” to refer to multiple disease processes that may have varying degrees of overlap (including but not limited to sequelae of critical illness and hospitalization in persons with COVID-19) and the entity of long COVID, which refers to prolonged health abnormalities in persons previously infected with SARS-CoV-2 who may or may not have required hospitalization. Of note, there is not yet a consensus on terminology, which will likely evolve with a better understanding of this condition.

Reported symptoms are wide-ranging and may involve nearly all organ systems, with fatigue, dyspnea, cognitive dysfunction, anxiety, and depression often described (2–5). Although abnormalities in imaging studies and functional testing have been reported, the long-term clinical significance of some of these findings is not yet clear (367). Postacute manifestations of COVID-19 have been seen in persons of all demographic groups and include reports of multisystem inflammatory syndrome in children (89). Although the epidemiology of the diverse manifestations of postacute COVID-19 is not yet known, the expansive global burden of SARS-CoV-2 infection suggests that the potential public health effects of postacute COVID-19 are significant if even a small proportion of persons with SARS-CoV-2 infection have prolonged recovery or do not return to their baseline health.

On 3 to 4 December 2020, the National Institute of Allergy and Infectious Diseases, in collaboration with other Institutes and Centers of the National Institutes of Health, convened a virtual workshop (available via videocast at https://videocast.nih.gov/watch=38878 and https://videocast.nih.gov/watch=38879) to summarize existing knowledge on postacute COVID-19 and to identify key knowledge gaps. The speakers and participants included epidemiologists, clinicians, clinical and basic scientists, and members of the affected community. The videocast was open to the general public and had more than 1200 registered participants.

SOURCE

UPDATED on 4/7/2021

‘Beyond a Reasonable Doubt’: COVID-19 Brain Health Fallout Is Real, Severe

Sarah Edmonds

April 07, 2021

Editor’s note: Find the latest COVID-19 news and guidance in Medscape’s Coronavirus Resource Center.

START QUOTE

COVID-19 survivors face a sharply elevated risk of developing psychiatric or neurologic disorders in the six months after they contract the virus — a danger that mounts with symptom severity, new research shows.

In what is purported to be the largest study of its kind to-date, results showed that among 236,379 COVID-19 patients, one third were diagnosed with at least one of 14 psychiatric or neurologic disorders within a 6-month span.

The rate of illnesses, which ranged from depression to stroke, rose sharply among those with COVID-19 symptoms acute enough to require hospitalization.  

“If we look at patients who were hospitalized, that rate increased to 39%, and then increased to about just under 1 in 2 patients who needed ICU admission at the time of the COVID-19 diagnosis,” Maxime Taquet, PhD, University of Oxford Department of Psychiatry, Oxford, United Kingdom, told a media briefing.

Incidence jumps to almost two thirds in patients with encephalopathy at the time of COVID-19 diagnosis, he added.

The study, which examined the brain health of 236,379 survivors of COVID-19 via a US database of 81 million electronic health records, was published online April 6 in The Lancet Psychiatry.

High Rate of Neurologic, Psychiatric Disorders

The research team looked at the first-time diagnosis or recurrence of 14 neurologic and psychiatric outcomes in patients with confirmed SARS-CoV-2 infections. They also compared the brain health of this cohort with a control group of those with influenza or with non-COVID respiratory infections over the same period. 

SOURCE

The Effects of Loneliness and Our Brain function: poorer physical and mental health

One review of the science of loneliness found that people with stronger social relationships have a 50 per cent increased likelihood of survival over a set period of time compared with those with weaker social connections. Other studies have linked loneliness to cardiovascular disease, inflammation, and depression.

For loneliness researchers the pandemic has provided an unprecedented natural experiment in the impact that social isolation might have on our brains. As millions of people across the world emerge from months of reduced social contact, a new neuroscience of loneliness is starting to figure out why social relationships are so crucial to our health.

Neural basis of Emotion

Desire for Social Interaction

Are there neurological differences between people who experience short-term isolation and those who have been isolated for long stretches of time? What kinds of social interactions satisfy our social cravings? Is a video call enough to quell our need for social contact, or do some people require an in-person connection to really feel satiated?

START QUOTE

Julianne Holt-Lunstad, a psychology professor at Brigham Young University in the US and the author of two major studies on social isolation and health. “We have a lot of data that very robustly shows that both isolation and loneliness put us at increased risk for premature mortality—and conversely, that being socially connected is protective and reduces our risk,” she says.

START QUOTE

“Trying to investigate isolation or loneliness is not as straightforward in humans. In humans, being lonely is not necessarily correlated with how many people are around you,” says Tomova. She is particularly interested in the impact that the pandemic might have had on young people whose cognitive and social skills are still developing. “I think we will see potentially some differences in how their social behavior developed or things like that,” she says. But as is always the case in the uncertain world of loneliness research, the opposite could be true. “It could also be that most people are fine, because maybe social media does fulfill our social needs really well.”

SOURCE

https://www.wired.co.uk/article/lockdown-loneliness-neuroscience

The Weird Science of Loneliness and Our Brains – Social isolation as been linked to poorer physical and mental health, but scientists are finally starting to understand its neurological impact

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T cells recognize recent SARS-CoV-2 variants

Reporter: Aviva Lev-Ari, PhD, RN

CD8+ T cell responses in COVID-19 convalescent individuals target conserved epitopes from multiple prominent SARS-CoV-2 circulating variants 

Andrew D ReddAlessandra NardinHassen KaredEvan M BlochAndrew PekoszOliver LaeyendeckerBrian AbelMichael FehlingsThomas C QuinnAaron A R TobianOpen Forum Infectious Diseases, ofab143, https://doi.org/10.1093/ofid/ofab143Published: 30 March 2021 Article history

Abstract

This study examined whether CD8+ T-cell responses from COVID-19 convalescent individuals (n=30) potentially maintain recognition of the major SARS-CoV-2 variants (n=45 mutations assessed). Only one mutation found in B.1.351-Spike overlapped with a previously identified epitope (1/52), suggesting that virtually all anti-SARS-CoV-2 CD8+ T-cell responses should recognize these newly described variants.

Key words:

CD8+ T cellSARS-CoV-2COVID-19Convalescent patients

Topic: 

SOURCE

https://academic.oup.com/ofid/advance-article/doi/10.1093/ofid/ofab143/6189113

Original paper:

Andrew D Redd, Alessandra Nardin, Hassen Kared, Evan M Bloch, Andrew Pekosz, Oliver Laeyendecker, Brian Abel, Michael Fehlings, Thomas C Quinn, Aaron A R Tobian, CD8+ T cell responses in COVID-19 convalescent individuals target conserved epitopes from multiple prominent SARS-CoV-2 circulating variants, Open Forum Infectious Diseases, 2021;, ofab143, https://doi.org/10.1093/ofid/ofab143

Tuesday, March 30, 2021

T cells recognize recent SARS-CoV-2 variants

Healthy Human T CellScanning electron micrograph of a human T lymphocyte (also called a T cell) from the immune system of a healthy donor. NIAID

What

When variants of SARS-CoV-2 (the virus that causes COVID-19) emerged in late 2020, concern arose that they might elude protective immune responses generated by prior infection or vaccination, potentially making re-infection more likely or vaccination less effective. To investigate this possibility, researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and colleagues analyzed blood cell samples from 30 people who had contracted and recovered from COVID-19 prior to the emergence of virus variants. They found that one key player in the immune response to SARS-CoV-2—the CD8+ T cell—remained active against the virus.

The research team was led by NIAID’s Andrew Redd, Ph.D., and included scientists from Johns Hopkins University School of Medicine, Johns Hopkins Bloomberg School of Public Health and the Immunomics-focused company, ImmunoScape.

The investigators asked whether CD8+ T cells in the blood of recovered COVID-19 patients, infected with the initial virus, could still recognize three SARS-CoV-2 variants: B.1.1.7, which was first detected in the United Kingdom; B.1.351, originally found in the Republic of South Africa; and B.1.1.248, first seen in Brazil. Each variant has mutations throughout the virus, and, in particular, in the region of the virus’ spike protein that it uses to attach to and enter cells. Mutations in this spike protein region could make it less recognizable to T cells and neutralizing antibodies, which are made by the immune system’s B cells following infection or vaccination.

Although details about the exact levels and composition of antibody and T-cell responses needed to achieve immunity to SARS-CoV-2 are still unknown, scientists assume that strong and broad responses from both antibodies and T cells are required to mount an effective immune response.  CD8+ T cells limit infection by recognizing parts of the virus protein presented on the surface of infected cells and killing those cells.

In their study of recovered COVID-19 patients, the researchers determined that SARS-CoV-2-specific CD8+ T-cell responses remained largely intact and could recognize virtually all mutations in the variants studied. While larger studies are needed, the researchers note that their findings suggest that the T cell response in convalescent individuals, and most likely in vaccinees, are largely not affected by the mutations found in these three variants, and should offer protection against emerging variants.   

Optimal immunity to SARS-Cov-2 likely requires strong multivalent T-cell responses in addition to neutralizing antibodies and other responses to protect against current SARS-CoV-2 strains and emerging variants, the authors indicate. They stress the importance of monitoring the breadth, magnitude and durability of the anti-SARS-CoV-2 T-cell responses in recovered and vaccinated individuals as part of any assessment to determine if booster vaccinations are needed. 

SOURCE

https://www.nih.gov/news-events/news-releases/t-cells-recognize-recent-sars-cov-2-variants

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Comparing COVID-19 Vaccine Schedule Combinations, or “Com-COV” – First-of-its-Kind Study will explore the Impact of using eight different Combinations of Doses and Dosing Intervals for Different COVID-19 Vaccines

Reporter: Aviva Lev-Ari, PhD, RN

 

The UK’s COVID-19 vaccine rollout commenced in December, and requires an individual to receive two doses of the same vaccine, either Pfizer/BioNTech’s BNT162b2 or AstraZeneca/Oxford’s ChAdOx1, with a maximum interval of 12 weeks between doses. As of February 3, 10 million first doses have been administered.

Com-COV has been classified as an “Urgent Public Health” study by the National Institutes for Health and Research (NIHR), and it’s hoped that the data produced may offer greater flexibility for vaccine delivery going forward.

“Given the inevitable challenges of immunizing large numbers of the population against COVID-19 and potential global supply constraints, there are definitely advantages to having data that could support a more flexible immunization program, if ever needed and approved by the medicines regulator,” Jonathan Van-Tam, deputy chief medical officer and senior responsible officer for the study, said in a press release.

The study will run for a 13-month period and will recruit over 800 patients across eight sites in the UK, including London – St George’s and UCL, Oxford, Southampton, Birmingham, Bristol, Nottingham and Liverpool.

Com-COV has eight different arms that will test eight different combinations of doses and dose intervals. This is tentative and subject to change should more COVID-19 vaccines be approved for use in the UK. The eight arms include the following dose combinations:

  • Pfizer/BioNTech and Pfizer/BioNTech – 28 days apart
  • Pfizer/BioNTech and Pfizer/BioNTech – 12 weeks apart – (control group)
  • Oxford/AstraZeneca and Oxford/AstraZeneca – 28 days apart
  • Oxford/AstraZeneca and Oxford/AstraZeneca – 12 weeks apart – (control group)
  • Oxford/AstraZeneca and Pfizer/BioNTech – 28 days apart
  • Oxford/AstraZeneca and Pfizer/BioNTech – 12 weeks apart
  • Pfizer/BioNTech and Oxford/AstraZeneca – 28 days apart
  • Pfizer/BioNTech and Oxford/AstraZeneca – 12 weeks apart

Aside from the logistical benefits of using alternative vaccines, there is scientific value to exploring how different vaccines and doses affect the human immune system.

Dr Peter English, consultant in communicable disease control, pointed out that the antigen used across the currently authorized COVID-19 vaccines is the same Spike protein. Therefore, the immune system can be expected to respond just as well if a different product is used for boosting. “It is also the case that many vaccines work better if a different vaccine is used for boosting – an approach described as heterologous boosting,” English said, referencing previously successful trials using Hepatitis B vaccines.

“It is also even possible that by combining vaccines, the immune response could be enhanced giving even higher antibody levels that last longer; unless this is evaluated in a clinical trial we just won’t know,” added Van-Tam.

If warranted by the study data, the Medicines and Healthcare products Regulatory Agency may consider reviewing and authorizing modifications to the UK’s vaccine regimen approach – but only time will tell.

“We need people from all backgrounds to take part in this trial, so that we can ensure we have vaccine options suitable for all. Signing up to volunteer for vaccine studies is quick and easy via the NHS Vaccine Research Registry,” Professor Andrew Ustianowski, national clinical lead for the NIHR COVID Vaccine Research Program, said

SOURCE

First-of-its-Kind Study Will Test Combination of Different COVID-19 Vaccines | Technology Networks

https://www.technologynetworks.com/biopharma/news/first-of-its-kind-study-will-test-combination-of-different-covid-19-vaccines-345245?utm_campaign=NEWSLETTER_TN_Biopharma

WATCH VIDEO

Different Types of COVID-19 Vaccines With Dr Seth Lederman Video | Technology Networks

https://www.technologynetworks.com/biopharma/videos/different-types-of-covid-19-vaccines-with-dr-seth-lederman-345207

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Rise of a trio of mutated viruses hints at an increase in transmissibility, speeding the virus’ leaps from one host to the next

Reporter: Aviva Lev-Ari, PhD, RN

“We have uncontrolled viral spread in much of the world,” says Adam Lauring, an infectious disease physician and virologist at the University of Michigan. “So the virus has a lot of opportunity to evolve.”

“The variants may be more transmissible, but physics has not changed,” says Müge Çevik, an infectious disease physician at the University of St. Andrews in Scotland.

Many changes don’t affect the virus’ function, and some even harm SARS-CoV-2’s ability to multiply, but they keep happening. “Viruses mutate; that’s what they do,” says Akiko Iwasaki, an immunologist at Yale School of Medicine in Connecticut.

U.K., Brazil, and South Africa. In the United Kingdom, variant B.1.1.7 likely drove the region’s record-setting spike of COVID-19 cases in January. The variant is now circulating in more than 60 countries, including the United States—and projections suggest it will become the most common virus variety in the U.S. by mid-March.

An independently arising lineage called P.1 might also be driving a wave of cases in Manaus, Brazil, where it accounted for nearly half of new COVID-19 infections in December. On January 26, Minnesotan officials reported the first U.S. case of P.1 in a resident who previously traveled to Brazil. And a third lineage raising alarms, known as B.1.351, was first spotted amid a December wave of infections in South Africa. On January 28, the first known U.S. cases of the variant were reported in South Carolina.

One specific mutation, known as N501Y, popped up independently in all three variants, suggesting it could provide an advantage to the virus. “That’s a sign that there is natural selection going on,” Lauring says. The N501Y mutation affects the virus’ spike protein, which is the key it uses to unlock entry into its host’s cells.

Another possibility is that new variants cause people who are infected to harbor more copies of the virus. This results in greater viral “shedding” in airborne droplets spewed when people talk, sing, cough, and breath.

mutations in 501Y.V2 could diminish the effectiveness of antibodies in the blood of people previously infected with the virus. But understanding whether that could lead to more re-infections, or if it could affect vaccine efficacy.

Dramatically scale up production of high-filtration masks for the general public.

Based on:

Why some coronavirus variants are more contagious‹and how we can stop them

https://www.nationalgeographic.com/science/2021/01/why-some-coronavirus-variants-are-more-contagious/?cmpid=org=ngp::mc=crm-email::src=ngp::cmp=editorial::add=SpecialEdition_20210129

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Inflammation and potential links with the microbiome: Mechanisms of infection by SARS-CoV-2

Reporter: Aviva Lev-Ari, PhD, RN

Mechanisms of infection by SARS-CoV-2, inflammation and potential links with the microbiome

Published Online:https://doi.org/10.2217/fvl-2020-0310

Human coronaviruses (HCoVs) were first isolated from patients with the common cold in the 1960s [1–3]. Seven HCoVs known to cause disease in humans have since been identified: HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, the SARS coronavirus (SARS-CoV), the Middle East respiratory syndrome coronavirus and the novel SARS-CoV-2 [4]. The latter was identified after a spike in cases of pneumonia of unknown etiology in Wuhan, Hubei Province, China during December 2019 and was initially named novel coronavirus (2019-nCoV) [5,6]. The virus was renamed SARS-CoV-2 according to the International Committee on Taxonomy of Viruses classification criteria due to its genomic closeness to SARS-CoV; the disease caused by this virus was named coronavirus disease (COVID-19) according to the WHO criteria for naming emerging diseases [7]. SARS-CoV-2 belongs to the genera Betacoronavirus and shares a different degree of genomic similarity with the other two epidemic coronaviruses: SARS-CoV (∼79%) and Middle East respiratory syndrome coronavirus (∼50%) [8].

COVID-19 has caused considerable morbidity and mortality worldwide and has become the central phenomenon that is shaping our current societies. Human-to-human transmission is the main route of spread of the virus, mainly through direct contact, respiratory droplets and aerosols [9–12]. Management of COVID-19 has been extremely challenging due to its high infectivity, lack of effective therapeutics and potentially small groups of individuals (i.e., asymptomatic or mild disease) rapidly spreading the disease [13–17]. Although research describing COVID-19 and the mechanisms of infection by SARS-CoV-2 and its pathogenesis has expanded rapidly, there is still much to be learnt. Important gaps in knowledge which remain to be elucidated are the dynamic and complex interactions between the virus and the host’s immune system, as well as the potential interspecies communications occurring between ecological niches encompassing distinct microorganisms in both healthy individuals and persons living with chronic diseases, and how these interactions could determine or modulate disease progression and outcomes.

In this review, we describe recent insights into these topics, as well as remaining questions whose answers will allow us to understand how interactions between the virus, the immune system and microbial components could possibly be related to disease states in patients with COVID-19, as well as existing studies of the microbiome in patients with COVID-19.

SOURCE

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