Infectious entry of PrV into CHO cells does not occur by endocytosis. RK13, CHO, and HveC-expressing CHO cells were infected with VSV (A) or PrV (B) and treated with PBS (bars 1), sodium azide (bars 2), ammonium chloride (bars 3), or chloroquine (bars 4). Indicated is the percentage of infectious events (plaques, foci, or infected single cells [Fig. 1]) compared to untreated control cells. Data are averages of three independent experiments. Vertical lines indicate standard deviations.