Abstract
In late 2019, a novel virus called SARS-CoV-2, expanded globally from Wuhan, China and was declared a pandemic on 11 March 2020 by the WHO. The mechanism of virus entry inside the host cell depends upon the cellular proteases including cathepsins, HAT, and TMPRSS2, which splits up the spike protein and causes further penetration. MERS coronavirus uses DPP4, while coronavirus HCoV-NL63 and SARS-CoV and SARS-CoV-2 employ ACE-2 as the key receptor. Cytokine storm syndrome was analyzed in critically ill nCOVID-19 patients and it is presented with high inflammatory mediators, systemic inflammation, and multiple organ failure. Among various inflammatory mediators, the level of interleukins (IL-2, IL-7, IL-10), G-CSF, MIP1A, MCP1, and TNF-α was reported to be higher in critically ill patients. Understanding this molecular mechanism of ILs, T cells, and dendritic cells will be helpful to design immunotherapy and novel drugs for the treatment of nCOVID-19 infection.