Lack of gD-mediated interference in PrV infection of CHO cells. PrV-1112 (A) and PrV gD− Pass (B) were titrated on CHO and gD-expressing CHO cells, RK13 and gD-expressing RK13 (RK13-gD) cells, and MDBK and gD-expressing MDBK (MT50-5) cells. Relative titers compared to parental RK13, MDBK, and CHO cells are indicated. In addition, parallel titrations were performed on HveC-expressing CHO cells after transfection with either a control plasmid (HveC) or a gD-expression plasmid [HveC (gD)]. Data are averages of three independent experiments. Vertical lines indicate standard deviations.