Coronary Diseases

Virus in Body

Virus entry is a finely regulated process requiring a series of interactions between the virion and host cell. Following the conjunction with the target receptor, COVID fuse its envelope with the membrane of the host cell. These processes are forced by the conformational change of S protein, which is triggered by not only the target receptor binding but also PH acidification and proteolytic cleavage led by cell surface or endosomal proteases such as transmembrane protease serine 2, furin, cathepsin  and trypsin. Cleavages of S protein are facilitated at two sites: the boundary between the S1 and S2 subunit and the conserved site upstream of the fusion peptide. The former one is aimed at releasing RBD from the membrane fusion subunit, and the latter one is important for the exposure of the fusion peptide, hydrophobic in general, which acts as an anchor to target membrane. Then the fusion domain adopts two heptad repeats to form a compact coiled-coil conformation called 6-helix bundle or 6HB. SARS-CoV-2 Entry Into Host Cells

• Hijacking of the Host Cell Machinery
• Host Immune Response to SARS-CoV-2 Infection
• Tissue Tropism and Organotropism
• Underlying Mechanisms