IL17A and COVID-19: We found modest increases in the Th17-type immune response–associated biomarkers IL-17 and IL-23 in COVID-19 patients and a more significant increase in IL-10 levels in all severity groups, with the highest concentrations observed in patients who succumbed to COVID-19 (Figure 3A, Supplemental Figure 10, and Supplemental Table 3), as previously reported (15, 19, 45).