scRNA-seq results of COVID-19 find that changes of host factors including EN-RAGE, TNFSF14, oncostatin M, ANXA1, FPR1, and S100A8/9 are correlated with disease severity, revealing the possible pathogenesis of severe COVID-19 and potential host therapeutic targets (Arunachalam et al., 2020; Guo et al., 2021; Ren et al., 2021). Here, S100A12 is linked to COVID-19.