34,35 However, substantial expression of pro-inflammatory cytokines such as IL-6, IL-1ß, IL-2, IL-10, IL1A, IL-8, and CXCL-10 was not detected in most of the profiled T or B cells from all COVID-19 samples (Supplementary Fig. 6), suggesting that (IL)-6, IL-10, and probably other cytokines returned back to normal levels after recovery of these COVID-19 patients. Here, CXCL10 is linked to COVID-19.