TNF and COVID-19: Cytokine storm, characterized by a systemic inflammatory reaction with increased production of proinflammatory cytokines such as IL6, TNF and inflammatory chemokines such as CCL2, CCL3 and CXCL10, has been proposed to play a key role in mediating mortality in severe COVID-19.25,62–64 Since RIPK1 kinase activity has an established role in mediating systemic inflammatory response,14 the activation of systemic inflammatory response in severe COVID-19 can serve as a biomarker for RIPK1 activation.