Fig. 2.

Cytokine storm consequent to SARS-CoV2 infection. The human JAK family, together with the STATs, primarily contribute to signaling transmission between extracellular receptors and the cell nucleus. Excessive COVID-19 associated cytokines bind to their receptors, leading to activation of JAKs and phosphorylation of downstream STATs.downstream Phosphorylated STATs regulate interferon induced gene expression, lymphocytes differentiation and proliferation, and participate in the cytokine-mediated immune overreaction, which eventually causes an inflammatory injury at the infected organ level, even at the systemic level.