FIG. 2.

Kinetics of SV40 entry into human glial cells. SV40 was preadsorbed to SVG cells for 30 min at 4°C, and then the cells were shifted to 37°C. At 0 min, 30 min, 1 h, 2 h, and 3 h following the shift to 37°C the cells were treated with either medium (+), preimmune antiserum (Pre), or anti-SV40 antiserum (Imm). The percentage of infected cells were scored at 3 days postinfection by counting V antigen-positive cells by an indirect immunofluorescence assay. The error bars were derived by calculating the standard error of the mean of the average number of positive cells counted within one experiment. Experiments were repeated at least three times.