COVID-19 pandemic: Mechanistic approaches and gender vulnerabilities

Cytidine deamination-induced perpetual immunity to SAR-CoV-2 infection is a potential new therapeutic target

As the world is racing to develop perpetual immunity to the SARS-CoV-2 virus. The emergence of new viral strains, together with vaccination and reinfections, are all contributing to a long-term immunity against the deadly virus that has taken over the world since its introduction to humans in late December 2019. The discovery that more than 95 percent of people who recovered from COVID-19 had long-lasting immunity and that asymptomatic people have a different immune response to SARS-CoV-2 than symptomatic people has shifted attention to how our immune system initiates such diverse responses. These findings have provided reason to believe that SARS-CoV-2 days are numbered. Hundreds of research papers have been published on the causes of long-lasting immune responses and variations in the numbers of different immune cell types in COVID 19 survivors, but the main reason of these differences has still not been adequately identified. In this article, we focus on the activation-induced cytidine deaminase (AID), which initiates molecular processes that allow our immune system to generate antibodies against SARS-CoV-2. To establish lasting immunity to SARS-CoV-2, we suggest that AID could be the key to unlocking it.

SAR-CoV-2 infection, emerging new variants and the role of activation induced cytidine deaminase (AID) in lasting immunity

As the world faces a fourth COVID-19 spike, scientists are learning a lot more about the new SARS-CoV-2 strains that were previously unknown. Currently, the Delta versions of SARS-CoV-2 have become the prevalent strains in much of the world since it first appeared in India in late 2020. Researchers believe they have discovered why Delta has been so successful: those infected with it create significantly more virus than those infected with the original strain of SARS-CoV-2, making it extremely contagious. This has redirected the focus to how our immune system defends us from these various pathogens and initiates such varied responses. Hundreds of research papers have been published on the origins of long-lasting immune responses and disparities in the numbers of different immune cell types in COVID 19 survivors, but the primary architect of these discrepancies has yet to be discovered. In this essay, we will concentrate on the primary architect protein, activation induced cytidine deaminase (AID), which triggers molecular processes that allow our immune system to produce powerful antibodies and SARS-CoV-2 specific B cells, allowing us to outwit the virus. We believe that if we ever achieve permanent immunity to SARS-CoV-2 infection, AID will be the key to releasing it.

Demographic and clinical factors associated with early hospital Coronovirus disease 2019 deaths in a low middle income setting: A record-based analysis of 20,641 deaths from India

Understanding the demographic and clinical characteristics cases and deaths is essential for better clinical and public health management of coronavirus disease-2019 (COVID-19) in resource-limited settings. We analyzed the COVID-19 deaths reported from India, to describe the demographic and clinical characteristics and identify the factors associated with early hospital deaths (within one day of hospitalization) and survival duration. We conducted a record review of the publicly available data on COVID-19 deaths reported between January 30th and November 30th, 2020. After imputation for missing data, we calculated unadjusted and adjusted prevalence ratio, and regression coefficient for factors associated with early hospital death and survival duration. Of the 20,641 COVID-19 deaths analyzed, a) 14,684 (71.1%) were males; b) 10,134 (50.9%) were aged < 65 years; c) 9,722 (47.1%) treated at public hospitals and d) 5405 (27.1%) were early hospital deaths. Breathlessness was the most common presenting complaint. Diabetes (11,075,53.7%), hypertension (95,77,46.5%) and coronary artery disease (2,821,13.7%) were the common comorbidities. After adjustment, early hospital death was significantly higher among patients aged <65 years, without severe acute respiratory illness (SARI) at admission, non-diabetics, and cared at public hospitals compared to their counterparts. Similarly, the survival duration was at least one day higher among patients presented with SARI, chronic liver disease and cared at a private hospital. The analysis covered >10% of India's COVID-19 deaths, providing essential information regarding the COVID-19 epidemiology. The characteristics associated with early hospital death and survival duration among the COVID-19 fatalities may be deliberated as markers for prognosis and compared with survivors.

Exploring the utility of extracellular vesicles in ameliorating viral infection-associated inflammation, cytokine storm and tissue damage

Extracellular vesicles (EVs) have emerged as potential mediators of intercellular communication. EVs are nano-sized, lipid membrane-bound vesicles that contains biological information in the form of proteins, metabolites and/or nucleic acids. EVs are key regulators of tissue repair mechanisms, such as in the context of lung injuries. Recent studies suggest that EVs have the ability to repair COVID19-associated acute lung damage. EVs hold great promise for therapeutic treatments, particularly in treating a potentially fatal autoimmune response and attenuate inflammation. They are known to boost lung immunity and are involved in the pathogenesis of various lung diseases, including viral infection. EV-based immunization technology has been proven to elicit robust immune responses in many models of infectious disease, including COVID-19. The field of EV research has tremendous potential in advancing our understanding about viral infection pathogenesis, and can be translated into anti-viral therapeutic strategies.