FIG. 4.

Effect of the timing of MAb 8 injection on infection by CPV. Cells incubated with CPV for 1 h at 0°C were warmed to 37°C and then injected with MAb 8 at various times between 1 and 12 h later. The percentage of cells that became infected after injection at the various times after warming was determined by staining for the injected MAb and for NS1 to indicate the virus infection. The percentage of infection of noninjected cells in the same cultures was used as a control.