Fig. 1.
In vitro B16ova tumor cells are resistant to reovirus oncolysis and replication. A, JAM-1 expression was assessed by flow cytometry. Gray, isotype control; black line, JAM-1. B, B16ova and B16tk cells were treated with serial dilutions of reovirus stock, and cell survival was determined at indicated time points by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Data representative of three experiments. C, viral progeny following infection at 1 pfu per cell was determined after three cycles of freeze thaw lysis by plaque assay. B16ova cells were seeded in duplicate wells at 5 × 105 and allowed to adhere overnight. D, lymphocytes from C57BL/6 mice were incubated with reovirus at different viral titer s at 4°C for 4 h, and seeded at a 1:1 ratio into B16 or B16ova cultures. Tumor cell death was assessed at 72 h after harvesting, by propidium iodide staining after gating out CD3+ lymphocytes. Data are mean values of duplicate wells ± SE, and representative of two experiments.