C4A and infection: This differential gene analysis showed only two genes (HECW2 and SATB1) that were upregulated following infection with all three viruses, versus nine common genes (ACHE, PIEZO1, ENO3, CDHR1, CCDC24, VCAM1, SLIT1, C4A, and ZNF321P) that were downregulated (Figure 3a).