TNF and COVID-19: Recent studies have reported elevated serum levels of TNFα in severe COVID-19 cases.9,13,24,81 In addition, a clinical trial from Wuhan, China, including 522 patients and 40 healthy controls showed that the concentration of TNFα was negatively correlated with T cell counts in COVID-19 patients.27 In contrast, a clinical trial from Chongqing, China, including 102 mild and 21 severe cases showed that TNFα levels were within the normal values in almost all COVID-19 patients (121/123).147 Thus, further research is urgently required to better understand the role of TNFα in COVID-CS.