Fig. 2.

STING agonist represses HCoV-229E amplification on human SAEC ALI. (A–C) Human SAEC ALI cells were differentiated and seeded in 24-well plates. The cells were infected with HCoV-229E at MOI of 0.01 on apical and treated with different doses of the indicated compounds in basal medium. (A) After 72 h, the slides were subjected to the H&E stains. (B) After 72 h, the infectious supernatant collected from apical cells by PBS wash were subjected to viral titration assay on MRC-5. (C) After 48 h, the viral RNAs were isolated from the infectious supernatant collected from apical cells by PBS wash and measured by real-time PCR. The data are presented as the means ± SDs of triplicate samples from one experiment and are representative of at least three independent experiments.