TNF and COVID-19: COVID-19 patients produced lower TNF-α, 62 times lower with LPS and 83 times lower with LPS + rhIFN-γ than healthy subjects (TNF-α pg/mL, median = LPS: 27 vs. 1671, and LPS + rhIFN-γ: 20 vs. 165, patients vs. healthy controls) (Figure 2e).