Figure 2.
Time-of-addition experiments of BLF with HCoV-OC43 or SARS-CoV-2 pseudovirus particles. (A) Representative images of intracellular HCoV-OC43 virus detected by immunofluorescence staining using HCoV-OC43 specific antibody. Images were taken by ZoeTM Fluorescent Cell Imager (BioRad). (B) Illustration of the time periods when BLF (1000 µg/ml) was present in the time-of-addition experiments. Arrows represent the periods of time that BLF was present in the cell culture. (C) Quantification of HCoV-OC43 virus released into the cell culture medium using plaque assay. (D) Relative SARS-CoV-2 pseudovirus particle titers were quantified by measuring luciferase activity using Bright-Glo Luciferase Assay System and normalized to control. ***, p < 0.001 (student's t-test). Data are mean ± standard deviation of two replicates.