Fig. 2.

Only a low titer of virus infectivity of SARS-CoV was detected in the culture media from infected neural cell lines. The culture media from the same cell cultures in Fig. 1 on days 0 (no incubation in medium after adsorption followed by washing with PBS), 1, and 2 post-infection were subjected to infectivity titration using Vero E6 cells as described under Materials and methods. The TCID₅₀/ml obtained in individual infected cells are shown by means of triplicate experiments.