Fig. 3.

BST2 knockdown has no significant effects on HCoV-229E entry. (A) HeLa and HeLa/BST2⁻ cells were inoculated with HCoV-229E at 0.1 MOI for 1 h at 37 °C. At each indicated time, cells were fixed and expressed viral nucleocapsid (N) proteins were detected with a rabbit anti-N antibody and a secondary FITC-conjugated anti-rabbit antibody. Cells were then analyzed by flow cytometry. Percentages of infected cells were determined by dividing the number of FITC-positive cells by the number of total cells and multiplying by 100. (B) HeLa and HeLa/BST2‐ cells were infected with HCoV-229E at either 0.1 or 2 MOI. At 4, 6, or 12 h post-infection, cells were fixed, probed with a primary anti-229E N antibody and a secondary rhodamine-conjugated anti-rabbit antibody, and observed using a laser confocal microscope. Nuclei were stained with DAPI (blue). Mock-infected cells or cells not exposed to the primary antibody yielded no signal (data not shown).