ABSTRACT
The COVID-19 pandemic cost 7-8 million deaths worldwide, creating an unprecedented health and economic crisis. Affecting 700 million people globally, the magnitude of this pandemic is far from anything that humanity has encountered in recent times. A detailed investigation revealed that more than the SARS-CoV2 virus, the hyperactive immune system mediated injury as the real cause of mortality. Cytokine storm following viral infection leads to the surge of proinflammatory cytokines resulting in ARDS and lung injury. Anti-inflammatory intervention with anti-IL6 (anti-IL-6 receptor monoclonal antibodies (mAbs) (e.g., sarilumab, tocilizumab) and anti-IL-6 mAbs (i.e., siltuximab) and /or steroid-based approach lead to substantial protection and prevent death thereby implying the role of inflammation in COVID-19. In this short review, we summarized the dysregulated immune system in COVID-19 infection, investigating in detail the virus–host immune cross talks and presenting the possibilities of therapeutic intervention.
Subject(s)
COVID-19 , Lung DiseasesABSTRACT
Coronaviruses (CoVs) are one of the largest groups of positive-sense RNA virus families within the Nidovirales order, which are further classified into four genera: alpha, beta, gamma, and delta. Coronaviruses have an extensive range of natural hosts and are known to be responsible for a broad spectrum of diseases in multiple species. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) that has unleashed a global threat to public health and the economy. Coronaviruses are extensively present in birds and mammals, with horseshoe bats (Rhinolophus affinis), being the reservoir for the ongoing SARS-CoV-2 that seems to have resulted from a zoonotic spillover to the human host, causing respiratory infections, lung injury and Acute Respiratory Distress Syndrome(ARDS). About six coronavirus serotypes are linked with the disease in humans, namely HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV, SARS-CoV-2, and MERS-CoV. SARS-CoV-2 is the seventh CoV to infect humans. We analyzed the genome sequence of CoV-2 from isolates derived from China as well from India and encountered minute variations in their sequence. A cladogram analysis revealed the predominant strain circulating in India belongs to the A2a clad. We took one such strain (MT012098) and performed a rigorous in-silico genotypic and antigenic analysis to identify its relatedness to other strains. Further, we also performed a detailed prediction for B and T cell epitopes using BepiPred 2.0 server and NetCTL 1.2 server (DTU Bioinformatics), respectively. We hope this information may assist in an effective vaccine designing program against SARS-CoV-2.