2021, Vol.12 No.1
<b><span style="font-size:9.0pt;font-family:"">Figure 1. The development of COVID19.</span></b><span style="font-size:9.0pt;font-family:""> Viral infection: <span style="color:black;">TMPRSS2 cleaves the S protein of
SARS-CoV-2; The RBD on the S1 subunit binds to ACE2 on the cell surface.
Following entry into the cell, viral RNA is released and combined with RdRp to
synthesize a full-length negative-strand RNA as an RNA replication template.
After translation, structural proteins are localized to the inner membrane of
Golgi for assembly. Cytokine storm syndrome: The immune system is
over-activated, followed by the overproduction of multiple inflammatory
factors. Multiple immune cells are recruited. As a result, healthy cells are
damaged by overactive immune response. </span>Acute respiratory distress
syndrome: In the exudative phase, macrophages are activated and release
pro-inflammatory mediators, which leads to the aggregation of neutrophils and
monocytes. Activated neutrophils induce further damage. The injury leads to
loss of barrier function and fluid accumulation in the interstitium and
alveoli. In the proliferative period, the tissue homeostasis is recovered.</span>[Detail] ...