Fig. 2.

EGCG treatment decreases HCoV-OC43 induced cytotoxicity. (A) EGCG treatment reduces the cytotoxicity of HCoV-OC43 infections. RD cells were infected with mock or HCoV-OC43 and cell viability was evaluated with MTT assay. The experiments were performed at least in triplicate. The graph shows mean and standard error. Control vs EGCG treatment: ∗p < 0.05, ∗∗p < 0.005. (B) RD cells were infected with mock or HCoV-OC43 and cells were overlaid with agarose. To visualize the plaque formation, the infected cells were stained with crystal violets. The number indicates dilution of conditioned media.