Fig. 8.

Comparison of growth rates of SARS-CoVs at acute and persistent phases in Vero E6 and CaCo-2 cells. The Vero E6 and CaCo-2 cells were mock-infected (Mock) and infected at an MOI of 1 with SARS-CoV prepared from the Vero E6 cells that were acutely infected for 2 days (Acute) and from persistently SARS-CoV-infected for 5 months (Persistent). After adsorption for 1 h, the cells were washed with PBS. The total RNAs were extracted from the cells just after washing with PBS (Day 0) as a control and also from the cells that were cultured in complete medium at 37 °C for 10 dpi (Day 10). The culture medium was replaced with fresh complete medium every 2–3 days. The total RNAs were used for quantification of the SARS-CoV genomic RNA by RT-PCR using primers at the 1ab region.