TNFRSF1B and COVID-19: Conversely, compared to HD and LTBI/COVID-19, COVID-19 exhibited an increased frequency of TNFR2+ monocytes without stimulation (p<0.05), which persisted after stimulation with a spike (p<0.05), BCG (p<0.05), and BCG/spike (p<0.05) (Figure 2A, down).