FIG 4.

A549-ACE2 and Caco-2-ACE2 model cell line responses to SARS-CoV-2 infection. (A and B) Human A549-ACE2 (A) and Caco-2-ACE2 (B) cells were noninfected or incubated with SARS-CoV-2 at the indicated MOIs. Cells were harvested and then lysed for RNA extraction. Relative expression levels of the indicated IFN genes and ISGs were analyzed by RT-qPCR using both ActinB and GAPDH for normalization (left y axis), while viral replication was analyzed using RdRp primers and probe (right y axis). The means of three independent experiments are shown, with error bars representing the SD from the mean.