IL6 and COVID-19: Recently, a number of studies on the clinical characteristics of severe COVID-19 patients had shown that several proinflammatory cytokines, including IL-6, IL-10, IFN-γ, TNF-α, and others, are significantly elevated especially in those ICU patients infected by SARS-CoV-2, causing excessive activated immune response.41–45 The pathological relevance of these cytokines in SARS-CoV-2 infection indicated that their blockade may alleviate the inflammatory response and thus provide a feasible therapy for the treatment of COVID-19.