Feeds:
Posts
Comments

Posts Tagged ‘COVID-19 SARS-CoV-2’

Defective viral RNA sensing gene OAS1 linked to severe COVID-19

Reporter: Stephen J. Williams, Ph.D.

Source: https://www.science.org/doi/10.1126/science.abm3921

Defective viral RNA sensing linked to severe COVID-19

JOHN SCHOGGINS SCIENCE•28 Oct 2021•Vol 374, Issue 6567•pp. 535-536•DOI: 10.1126/science.abm39214,824

Why do some people with COVID-19 get sicker than others? Maybe exposure to a particularly high dose of the causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), accounts for the difference. Perhaps deficiencies in diet, exercise, or sleep contribute to worse illness. Although many factors govern how sick people become, a key driver of the severity of COVID-19 appears to be genetic, which is common for other human viruses and infectious agents (1). On page 579 of this issue, Wickenhagen et al. (2) show that susceptibility to severe COVID-19 is associated with a single-nucleotide polymorphism (SNP) in the human gene 2′-5′-oligoadenylate synthetase 1 (OAS1).The authors reasoned that SARS-CoV-2 should be inhibited by interferon-mediated antiviral responses, which are among the first cellular defense mechanisms produced in response to a viral infection. Interferons are a group of cytokines that induce the transcription of a large cadre of genes, many of which encode proteins with the potential to directly inhibit the invading virus. Wickenhagen et al. interrogated many hundreds of these putative antiviral proteins for their ability to suppress SARS-CoV-2 in cultured cells and found that OAS1 was particularly potent against SARS-CoV-2.OAS1 is an enzyme that is activated in the presence of double-stranded RNA, which is scattered along an otherwise singlestranded SARS-CoV-2 genome because of an assortment of RNA hairpins and other secondary structures. Once activated, OAS1 catalyzes the polymerization of adenosine triphosphate (ATP) into a second messenger, 2′-5′-oligoadenylate. This then triggers the conversion of ribonuclease L (RNaseL) into its active form so that it can cleave viral RNA, effectively blunting viral replication (3). Wickenhagen et al. found that OAS1 is expressed in respiratory tissues of healthy donors and COVID-19 patients and that it interacts with a region of the SARS-CoV-2 genome that contains double-stranded RNA secondary structures (see the figure).OAS1 exists predominantly as two isoforms in humans—a longer isoform (p46) and a shorter version (p42). Genetic variation dictates which isoform will be expressed. In humans, p46 is expressed in people who have a SNP that causes alternative splicing of the OAS1 messenger RNA (mRNA). This results in the utilization of a terminal exon that is not used to translate p42. Thus, the carboxyl terminus of the p46 OAS1 protein contains a distinct four–amino acid motif that forms a prenylation site. Prenylation is a posttranslational modification that targets proteins to membranes. In cell culture experiments, Wickenhagen et al. showed that only OAS1 p46, but not p42, could inhibit SARS-CoV-2. However, when the prenylation site of p46 was engineered into p42, this chimeric p42 protein was able to inhibit SARS-CoV-2, which strongly implicates a role for OAS1 specifically at membranes.Why are membranes important? SARS-CoV-2, like all coronaviruses, co-opts cellular membranes at the endoplasmic reticulum to form double-membrane vesicles, in which the virus replicates its genome. Thus, membrane-bound OAS1 p46 may be specifically activated by RNA viruses that form membrane-bound vesicles for replication. Indeed, the unrelated cardiovirus A, which also forms vesicular membranous structures, was inhibited by OAS1. Conversely, other respiratory RNA viruses, such as human parainfluenza virus type 3 and human respiratory syncytial virus, which do not use membrane-tethered vesicles for replication, were not inhibited by p46.Wickenhagen et al. examined a cohort of 499 COVID-19 patients hospitalized in the UK. Whereas all patients expressed OAS1, 42.5% of them did not express the antiviral p46 isoform. These patients were statistically more likely to have severe COVID-19 (be admitted to the intensive care unit). This suggests that OAS1 is an important antiviral factor in the control of SARS-CoV-2 infection and that its inability to activate RNaseL results in prolonged infections and severe disease, although other factors likely contribute. The authors also examined animals known to harbor different coronaviruses. They found evidence for prenylated OAS1 proteins in mice, cows, and camels. Notably, horseshoe bats, which are considered a possible reservoir for SARS-related coronaviruses (4), lack a prenylation motif in their OAS1 because of genomic changes that eliminated the critical four-amino acid motif. A horseshoe bat (Rhinolophus ferrumequinum) OAS1 was unable to inhibit SARS-CoV-2 infection in cell culture. Conversely, the black flying fox (Pteropus alecto)—a pteropid bat that is a reservoir for the Nipah and Hendra viruses, which can also infect humans—possesses a prenylated OAS1 that can inhibit SARS-CoV-2. These findings indicate that horseshoe bats may be genetically and evolutionarily primed to be optimal reservoir hosts for certain coronaviruses, like SARS-CoV-2.Other studies have now shown that the p46 OAS1 variant, which resides in a genomic locus inherited from Neanderthals (57), correlates with protection from COVID-19 severity in various populations (89). These findings mirror previous studies indicating that outcomes with West Nile virus (10) and hepatitis C virus (11) infection, both of which also use membrane vesicles for replication, are also associated with genetic variation at the human OAS1 locus. Another elegant functional study complements the findings of Wickenhagen et al. by also demonstrating that prenylated OAS1 inhibits multiple viruses, including SARS-CoV-2, and is associated with protection from severe COVID-19 in patients (12).There is a growing body of evidence that provides critical understanding of how human genetic variation shapes the outcome of infectious diseases like COVID-19. In addition to OAS1, genetic variation in another viral RNA sensor, Toll-like receptor 7 (TLR7), is associated with severe COVID-19 (1315). The effects appear to be exclusive to males, because TLR7 is on the X chromosome, so inherited deleterious mutations in TLR7 therefore result in immune cells that fail to produce normal amounts of interferon, which correlates with more severe COVID-19. Our knowledge of the host cellular factors that control SARS-CoV-2 is rapidly increasing. These findings will undoubtedly open new avenues into SARS-CoV-2 antiviral immunity and may also be beneficial for the development of strategies to treat or prevent severe COVID-19.

References and Notes

1J. L. Casanova, Proc. Natl. Acad. Sci. U.S.A.112, E7118 (2015).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR2A. Wickenhagen et al., Science374, eabj3624 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR3H. Kristiansen, H. H. Gad, S. Eskildsen-Larsen, P. Despres, R. Hartmann, J. Interferon Cytokine Res.31, 41 (2011).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR4S. Lytras, W. Xia, J. Hughes, X. Jiang, D. L. Robertson, Science373, 968 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR5S. Zhou et al., Nat. Med.27, 659 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR6H. Zeberg, S. Pääbo, Proc. Natl. Acad. Sci. U.S.A.118, e2026309118 (2021).CROSSREFPUBMEDGOOGLE SCHOLAR7F. L. Mendez, J. C. Watkins, M. F. Hammer, Mol. Biol. Evol.30, 798 (2013).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR8A. R. Banday et al., medRxiv2021).GO TO REFERENCECROSSREFGOOGLE SCHOLAR9E. Pairo-Castineira et al., Nature591, 92 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR10J. K. Lim et al., PLOS Pathog.5, e1000321 (2009).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR11M. K. El Awady et al., J. Gastroenterol. Hepatol.26, 843 (2011).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR12F. W. Soveg et al., eLife10, e71047 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR13T. Asano et al., Sci. Immunol.6, eabl4348 (2021).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR14C. Fallerini et al., eLife10, e67569 (2021).CROSSREFPUBMEDGOOGLE SCHOLAR15C. I. van der Made et al., JAMA324, 663 (2020).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR

For more on COVID-19 Please see our Coronavirus Portal at

Read Full Post »

Epidemiological measurement on COVID-19 pandemic may have statistical biases which might affect next variant responses

Reporter: Stephen J. Williams Ph.D.

Source: https://www.science.org/doi/10.1126/science.abi6602

From the jounal Science

Tackling the pandemic with (biased) data

CHRISTINA PAGEL AND CHRISTIAN A. YATESSCIENCE•22 Oct 2021•Vol 374, Issue 6566•pp. 403-404•DOI: 10.1126/science.abi66027,757

Accurate and near real-time data about the trajectory of the COVID-19 pandemic have been crucial in informing mitigation policies. Because choosing the right mitigation policies relies on an accurate assessment of the current state of the local epidemic, the potential ramifications of misinterpreting data are serious. Each data source has inherent biases and pitfalls in interpretation. The more data sources that are interpreted in combination, the easier it is to detect genuine changes in an epidemic. Recently, in many countries, this has involved disentangling the varying impact of rising but heterogeneous vaccination rates, relaxation of mitigations, and the emergence of new variants such as Delta.The exact data collected and their accuracy will vary by country. Typical data common to many countries are numbers of tests, confirmed cases, hospital and intensive care unit (ICU) admissions and occupancy, deaths, and vaccinations (1). Many countries additionally sequence a proportion of new positive tests to identify and track emerging variants. Some countries also now collect and publish data on infections, hospitalizations, and deaths by vaccination status (e.g., Israel and the UK). Stratifying all available data by different demographic factors (e.g., age, location, measures of deprivation, and ethnicity) is crucial for understanding patterns of spread, potential impact of policies, and efficacy of vaccines (age, timing of breakthrough infections, and prevalent variants).It is also necessary to be aware of what data are not being collected. For example, persistent symptoms of COVID-19 (Long Covid) were recognized as a long-term adverse outcome by the autumn of 2020. However, no simple diagnostic test has been associated with the up to 200 different reported symptoms (2). Counting Long Covid relies on a clinical diagnosis, based on a history of having had COVID-19 and a failure to fully recover, with development of some characteristic symptoms and with no obvious alternative cause (3). These features make it very difficult to measure routinely, and so it rarely is. As a result, Long Covid is often neglected in decision-making. Failure to account for the disease load associated with Long Covid may lead to an unnecessary long-term societal health burden.The feedback between different types of outcomes, different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, different mitigation policies (including vaccination), and individual risks (a combination of exposure and clinical risk) is complex and must be factored into both interpretation of data and the development of policy. Using all available data to quantify transmission is crucial to ensuring rapid and effective responses to early phases of renewed exponential growth and to evaluating mitigation measures. Relying too much on a single data source, or without disaggregating data, risks fundamentally misunderstanding the state of the epidemic.The inherent biases and lags in data are particularly important to understand from the point of view of policy-makers. Because of the natural time scales of COVID-19 disease progression (see the figure), policy changes can take several weeks to show up in the data. Purely reactive policy-making is likely to be ineffective. When cases are rising, increases in hospital admissions and deaths will follow. When a new variant is outcompeting existing strains, it is likely to become dominant without action to suppress. The precautionary principle suggests acting early and emphatically. Conversely, when releasing restrictions, governments must wait long enough to assess them before continuing with re-opening.The most up-to-date indicator of the state of the epidemic is typically the number of confirmed cases, as ascertained through testing of both symptomatic individuals and those tested frequently regardless of symptoms. Symptom-based testing is likely to pick up more adults and fewer younger individuals (4). Infections in children are harder to detect: children are more likely to be asymptomatic than adults, are harder to administer tests to (particularly young children), are often exposed to other viruses with similar symptoms, and can present with symptoms that are atypical in adults (e.g., abdominal pain or nausea). Children under 12 are not routinely offered the COVID-19 vaccination, and their mixing in schools provides ongoing opportunities for the virus to circulate, so it will be important for countries to track infections in children as accurately as possible. Other testing biases include accessibility, reporting lags, and the ability to act lawfully upon receiving a positive result. Substantial changes in the number of people seeking tests may further confound case figures (5). Case positivity rates may provide a more accurate reflection of the state of the epidemic (6) but are dependent on the mix of symptomatic and asymptomatic people being tested.SARS-CoV-2 variants have been an important driver of local epidemics in 2021. The four main SARS-CoV-2 variants of concern, to date, are B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), and B.1.617.2 (Delta). Some have been more transmissible (Alpha), some have substantial resistance to previous infection or vaccines (Beta), and some have elements of both (Gamma and Delta) (7). Currently, the high transmissibility of Delta combined with some immune evasion has made it the world’s dominant variant. Determining which variants pose a substantial threat is difficult and takes time, particularly when many variants cocirculate. This is especially true for situations in which a dominant variant is declining, and a new one growing. While the declining variant remains dominant, its decrease masks increases in the new variant because case numbers remain unchanged or fall overall. Only when a new variant becomes dominant does its growth become apparent in aggregated case data, by which time it is, by definition, too late to contain its spread. This dynamic has been observed across the world with Delta over the latter half of 2021.With multiple variants circulating, there are, effectively, multiple epidemics occurring in parallel, and they must be tracked separately. This typically requires the availability of sequencing data, which is unfortunately limited in most countries. Sequencing takes time and so is typically a few weeks out of date. These lags, and the uncertainty in sampling, can lead to hesitancy in acting. The rapid path to dominance of the Delta variant in the UK highlights the need for action when a quickly growing variant represents a few percent (or less) of overall cases.Hospital admissions or occupancy data do not suffer the same biases associated with testing behaviors and provide unequivocal evidence of widespread transmission, its geography, and demographics. However, hospital admissions lag infections more than reported cases do, rendering these data less useful for proactive decision-making. Hospital data are also biased toward older people, who are more likely to suffer severe COVID-19, and now, unvaccinated populations. ICU occupancy data show a younger age profile than admissions because younger patients have a better chance of benefitting from the invasive treatment procedures (8).Deaths are the most lagged indicator, typically occurring 3 or more weeks after infection and with an additional lag in registration and reporting. Death data should never be used to inform real-time policy decisions. Instead, death figures can act as an eventual measure of the success of a country’s epidemic strategy and implementation. The age distribution of those who eventually die from COVID-19 is different from other metrics of the epidemic—skewed furthest toward older age groups (9). Those with clinical risk factors (such as immunodeficiency, obesity, or existing lung conditions), high exposure (health care workers and low-income workers), and the unvaccinated are overrepresented in COVID-19 deaths.In countries with high vaccination rates, vaccination has had a substantial impact—reducing COVID-19 cases, hospitalizations, and deaths. However, when looking at the raw numbers in highly vaccinated populations, it can be the case that more fully vaccinated people are dying of COVID-19 than unvaccinated. If these raw statistics are misinterpreted—or worse, deliberately misused—they can damage vaccine confidence. More vaccinated people may die than unvaccinated because such a high proportion of people are vaccinated (10). This does not mean vaccines are not effective at preventing death. Looking at the rates of death in vaccinated and unvaccinated individuals separately within age groups demonstrates that vaccines provide considerable protection against severe disease and death. This example illustrates how important it is to curate and manage the way in which data are presented.

COVID-19 progressionAn approximate timeline from infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to various outcomes. When current infections show up in different data sources depends on this timeline. Collecting data for Long Covid, asymptomatic infection, and vaccine history will improve understanding of the pandemic.GRAPHIC: N. CARY/SCIENCE

Each country has established its own vaccination priority lists and dosing schedules to best achieve its goals (1112). Each of these strategies will manifest differently in the data. Additionally, many countries are using multiple vaccines in tandem and administer them differently for different demographics. Some countries are vaccinating adolescents, and others are not or not offering them the full approved dose. Most vaccines require two doses, spaced between 3 and 12 weeks apart, except for the Johnson & Johnson single-dose vaccine. This matters, particularly as variants spread, because different vaccines have different effectiveness after one and two doses, different timelines to full effectiveness, and different effectiveness against variants (13).Data published on the vaccination delivery itself must thus go beyond the raw numbers of people vaccinated. Vaccine uptake must be reported by whether fully or partially (one-dose in a two-dose regimen) vaccinated and using the whole population as a denominator. It is vital to disaggregate vaccine data by age, gender, and ethnicity as well as location so that it is possible, for example, to understand the impact of deprivation on vaccine coverage or vaccine hesitancy in particular demographics. When interpreting vaccination data, it is important to remember that there is also a lag between delivery and the build-up of immunity.Data on reinfection and post-vaccination (breakthrough) infection are also important to determine the relative benefits of infection-mediated and vaccine-mediated immunity and the length of protection offered. Studies that show those who were immunized earlier were acquiring COVID-19 with higher rates than those vaccinated more recently may suggest waning vaccine protection (14). Such studies have already prompted vaccine booster programs in some countries. However, any study that suggests waning immunity must be extremely careful to ensure that the “early” and “recent” subgroups are properly controlled. Differences in prior exposure, affluence, education level, age, and other demographic factors between these cohorts may be enough to explain the disparities in SARS-CoV-2 infection rates, even in the absence of waning immunity. Waning immunity must also be reported separately for different outcomes; for example, there might be waning in terms of preventing symptomatic infection but far less or none in preventing death (15). Additionally, there are ethical concerns about mass booster programs in high-income countries while many lower-income countries have been unable to procure vaccines.Moving into the vaccination era, reported cases, hospitalizations, and deaths should also be disaggregated by vaccination status (and by which vaccine), which will be easier in countries where national linked datasets exist. Additionally, incorporating Long Covid into routine reporting and policy-making is crucial. Consistent diagnostic criteria and well-controlled studies will be vital to this effort. These elusive data will be of critical importance to navigate our way successfully out of the pandemic.

Acknowledgments

C.P. and C.A.Y. are both members of Independent SAGE: www.independentsage.org.

References and Notes

1M. Roser et al., Our World in Data (2021); https://bit.ly/3kepLgw.GO TO REFERENCEGOOGLE SCHOLAR2H. E. Davis et al., E. Clin. Med.38, 101019 (2021).GO TO REFERENCEGOOGLE SCHOLAR3M. Sivan, S. Taylor, BMJ371, m4938 (2020).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR4S. M. Moghadas et al., Proc. Natl. Acad. Sci. U.S.A.117, 17513 (2020).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR5J. Wise, BMJ370, m3678 (2020).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR6D. Dowdy, G. D’Souza, COVID-19 Testing: Understanding the “Percent Positive” (2020); https://bit.ly/3CeN8wl.GO TO REFERENCEGOOGLE SCHOLAR7C. E. Gómez et al., Vaccines (Basel)9, 243 (2021).CROSSREFPUBMEDGOOGLE SCHOLAR8A. B. Docherty et al., BMJ369, 1985 (2020).GO TO REFERENCECROSSREFPUBMEDGOOGLE SCHOLAR9Office for National Statistics, Deaths registered weekly in England and Wales by age and sex: covid-19 (2021); https://bit.ly/3Ci2obS.

For articles on Issues of Bias in Science on this Open Access Journal see

From @Harvardmed Center for Bioethics: The Medical Ethics of the Corona Virus Crisis

Live Notes from @HarvardMed Bioethics: Authors Jerome Groopman, MD & Pamela Hartzband, MD, discuss Your Medical Mind

Read Full Post »

Will COVID become a disease of the young?

Reporter: Danielle Smolyar, Research Assistant 3 – Text Analysis for 2.0 LPBI Group’s TNS #1 – 2020/2021 Academic Internship in Medical Text Analysis (MTA)

An increase of infections among youth who are unvaccinated in countries with high vaccination rates is getting noticed in the role of young people in the pandemic.

On June 21 is Ross Ministry of health recommended that all individuals between the ages of 12 and 15 should be vaccinated. This makes the nation one of the few that have been approved vaccinations for younger kids. This decision came about in response too many other countries with high rates of vaccination are experiencing an increase in numbers of infections that are found to be in younger age groups.

Israel’s vaccination campaign which has reached to more than 85% of the adult population to be vaccinated noticed that case numbers are dropping around a dozen daily in the month of June. At the end of June, they have realized that the cases began to rise to more than 100 cases a day. These cases were found in kids under the age of 16 which is why the government decided to allow vaccinations.

Ran Balicer, and epidemiologists at Israel’s largest healthcare provider in Tel Aviv said that the younger profile is not surprising.

image source: https://www.nature.com/articles/d41586-021-01862-7

This trend that Israel started to notice is not just happening in Israel. The United States and the United Kingdom COVID-19, “become a disease of the unvaccinated, who are predominantly young”, says Joshua Goldstein, a demographer at the University of California, Berkeley. Stated in the article. 

This trend has been occurring in the countries where the older population were being vaccinated first. Follow the drop in age because they were vaccinating older people who are the most at risk for the disease.

This shift has shut attention to the studies of transmission in the younger age groups. Karin Magnusson immunologist said that it has come very important to understand the burden of the disease among the younger children. 

Magnusson on the impact of COVID-19 in children in Norway. On June 5 pre-print she reported that children see their doctor regularly up to six months after contracting Covid-19.

Balicer, is studying the virus spread in multi-generational households in Israel. Going beyond whether vaccinating children or not the patterns of COVID-19 infection have caused discussions about mask wearing to adolescence and kids in Israel. 

As stated in the article, “As the burden of cases shifts towards younger people, arguments for vaccinating adolescents will become slightly more compelling,” agrees Nick Bundle, an epidemiologist at the European Centre for Disease Prevention and Control in Stockholm.” However, the risk of disease in children still is low and in other countries the total number of cases have declined.

Countries also need to consider the global contacts. As stated in the article, “Are we really better off giving the vaccine to kids in rich countries than to older people [in less wealthy countries] where it might have a much bigger impact on people’s lives?” says Jennie Lavine, who studies infectious-disease dynamics at Emory University in Atlanta, Georgia. “It seems hard for me to imagine a really good argument for that.”

Oh there is a downward shift and the average age of infected with COVID-19 in countries with high COVID-19 vaccination rates it may be short-lived. There could be a few scenarios where the shift could bounce back says Henrik Salje, who is an infectious disease epidemiologist at the University of Cambridge, UK. Many of the countries could start vaccinating the adolescence just like Israel and the United States are already doing so. 

Bundle says that COVID- 19 can still be present in younger kids. “But how big a problem that is, is not a simple thing to respond to.”

SOURCE: Mallapaty, S. (2021, July 8). Will COVID become a disease of the young? Nature News. https://www.nature.com/articles/d41586-021-01862-7

Other related articles published on this Open Access Online Scientific Journal include the following:

Reporter: Jason S Zielonka, MD

Why Do Some COVID-19 Patients Infect Many Others, Whereas Most Don’t Spread the Virus At All?

Reporter: Stephen J. Williams, Ph.D

Recent Grim COVID-19 Statistics in U.S. and Explanation from Dr. John Campbell: Why We Need to be More Proactive

Reporter: Irina Robu

The race for a COVID-19 vaccine: What’s ahead ?

Reporter: Aviva Lev-Ari, PhD, RN

COVID vaccines by Pfizer, AstraZeneca are probed in Europe after reports of heart inflammation, rare nerve disorder

Reporter: Dr. Premalata Pati, Ph.D., Postdoc

The NIH-funded adjuvant improves the efficacy of India’s COVID-19 vaccine.

Read Full Post »

The NIH-funded adjuvant improves the efficacy of India’s COVID-19 vaccine.

Curator and Reporter: Dr. Premalata Pati, Ph.D., Postdoc

Anthony S. Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID), Part of National Institute of Health (NIH) said,

Ending a global pandemic demands a global response. I am thrilled that a novel vaccine adjuvant developed in the United States with NIAID support is now included in an effective COVID-19 vaccine that is available to individuals in India.”

Adjuvants are components that are created as part of a vaccine to improve immune responses and increase the efficiency of the vaccine. COVAXIN was developed and is manufactured in India, which is currently experiencing a terrible health catastrophe as a result of COVID-19. An adjuvant designed with NIH funding has contributed to the success of the extremely effective COVAXIN-COVID-19 vaccine, which has been administered to about 25 million individuals in India and internationally.

Alhydroxiquim-II is the adjuvant utilized in COVAXIN, was discovered and validated in the laboratory by the biotech company ViroVax LLC of Lawrence, Kansas, with funding provided solely by the NIAID Adjuvant Development Program. The adjuvant is formed of a small molecule that is uniquely bonded to Alhydrogel, often known as alum and the most regularly used adjuvant in human vaccines. Alhydroxiquim-II enters lymph nodes, where it detaches from alum and triggers two cellular receptors. TLR7 and TLR8 receptors are essential in the immunological response to viruses. Alhydroxiquim-II is the first adjuvant to activate TLR7 and TLR8 in an approved vaccine against an infectious disease. Additionally, the alum in Alhydroxiquim-II activates the immune system to look for an infiltrating pathogen.

Although molecules that activate TLR receptors strongly stimulate the immune system, the adverse effects of Alhydroxiquim-II are modest. This is due to the fact that after COVAXIN is injected, the adjuvant travels directly to adjacent lymph nodes, which contain white blood cells that are crucial in recognizing pathogens and combating infections. As a result, just a minimal amount of Alhydroxiquim-II is required in each vaccination dosage, and the adjuvant does not circulate throughout the body, avoiding more widespread inflammation and unwanted side effects.

This scanning electron microscope image shows SARS-CoV-2 (round gold particles) emerging from the surface of a cell cultured in the lab. SARS-CoV-2, also known as 2019-nCoV, is the virus that causes COVID-19. Image Source: NIAID

COVAXIN is made up of a crippled version of SARS-CoV-2 that cannot replicate but yet encourages the immune system to produce antibodies against the virus. The NIH stated that COVAXIN is “safe and well tolerated,” citing the results of a phase 2 clinical investigation. COVAXIN safety results from a Phase 3 trial with 25,800 participants in India will be released later this year. Meanwhile, unpublished interim data from the Phase 3 trial show that the vaccine is 78% effective against symptomatic sickness, 100% effective against severe COVID-19, including hospitalization, and 70% effective against asymptomatic infection with SARS-CoV-2, the virus that causes COVID-19. Two tests of blood serum from persons who had received COVAXIN suggest that the vaccine creates antibodies that efficiently neutralize the SARS-CoV-2 B.1.1.7 (Alpha) and B.1.617 (Delta) variants (1) and (2), which were originally identified in the United Kingdom and India, respectively.

Since 2009, the NIAID Adjuvant Program has supported the research of ViroVax’s founder and CEO, Sunil David, M.D., Ph.D. His research has focused on the emergence of new compounds that activate innate immune receptors and their application as vaccination adjuvants.

Dr. David’s engagement with Bharat Biotech International Ltd. of Hyderabad, which manufactures COVAXIN, began during a 2019 meeting in India organized by the NIAID Office of Global Research under the auspices of the NIAID’s Indo-US Vaccine Action Program. Five NIAID-funded adjuvant investigators, including Dr. David, two representatives of the NIAID Division of Allergy, Immunology, and Transplantation, and the NIAID India representative, visited 4 top biotechnology companies to learn about their work and discuss future collaborations. The delegation also attended a consultation in New Delhi, which was co-organized by the NIAID and India’s Department of Biotechnology and hosted by the National Institute of Immunology.

Among the scientific collaborations spawned by these endeavors was a licensing deal between Bharat Biotech and Dr. David to use Alhydroxiquim-II in their candidate vaccines. During the COVID-19 outbreak, this license was expanded to cover COVAXIN, which has Emergency Use Authorization in India and more than a dozen additional countries. COVAXIN was developed by Bharat Biotech in partnership with the Indian Council of Medical Research’s National Institute of Virology. The company conducted thorough safety research on Alhydroxiquim-II and undertook the arduous process of scaling up production of the adjuvant in accordance with Good Manufacturing Practice standards. Bharat Biotech aims to generate 700 million doses of COVAXIN by the end of 2021.

NIAID conducts and supports research at the National Institutes of Health, across the United States, and across the world to better understand the causes of infectious and immune-mediated diseases and to develop better methods of preventing, detecting, and treating these illnesses. The NIAID website contains news releases, info sheets, and other NIAID-related materials.

Main Source:

https://www.miragenews.com/adjuvant-developed-with-nih-funding-enhances-587090/

References

  1. https://academic.oup.com/cid/advance-article-abstract/doi/10.1093/cid/ciab411/6271524?redirectedFrom=fulltext
  2. https://academic.oup.com/jtm/article/28/4/taab051/6193609

Other Related Articles published in this Open Access Online Scientific Journal include the following:

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

https://pharmaceuticalintelligence.com/2021/02/08/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-diffe/

Thriving Vaccines and Research: Weizmann Institute Coronavirus Research Development

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

https://pharmaceuticalintelligence.com/2021/05/04/thriving-vaccines-and-research-weizmann-coronavirus-research-development/

National Public Radio interview with Dr. Anthony Fauci on his optimism on a COVID-19 vaccine by early 2021

Reporter: Stephen J. Williams, PhD

https://pharmaceuticalintelligence.com/2020/07/19/national-public-radio-interview-with-dr-anthony-fauci-on-his-optimism-on-a-covid-19-vaccine-by-early-2021/

Cryo-EM disclosed how the D614G mutation changes SARS-CoV-2 spike protein structure

Reporter: Dr. Premalata Pati, Ph.D., Postdoc

https://pharmaceuticalintelligence.com/2021/04/10/cryo-em-disclosed-how-the-d614g-mutation-changes-sars-cov-2-spike-protein-structure/

Updates on the Oxford, AstraZeneca COVID-19 Vaccine

Reporter: Stephen J. Williams, PhD

https://pharmaceuticalintelligence.com/2020/06/16/updates-on-the-oxford-astrazeneca-covid-19-vaccine/

Read Full Post »

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/

Read Full Post »

%d bloggers like this: