IL17A and COVID-19: The proteins in the IL-17 signaling pathway were highly connected to the proteins in the antigen processing and presentation pathway through JUN, which was a male-biased transcription factor reported in Genotype-Tissue Expression (GTEx) database.33 TAB3 is an activator of JUN in the IL-17 signaling pathway, and an elevated RNA expression of TAB3 (q = 7.5 × 10−9) is observed in squamous cells of male patients with critical COVID-19 (Fig. 3c, d).