TNF and lymphopenia: Peripheral blood examinations on admission in the majority of patients with COVID-19 displayed lymphopenia, elevated infection-related biomarkers (i.e., procalcitonin, erythrocyte sedimentation rate, serum ferritin, and C-reactive protein) (20) and several elevated inflammatory cytokines (i.e., tumor necrosis factor (TNF)-α, interleukin (IL)-2R and IL-6).