Differential cell killing of normal and transformed human lung fibroblasts by reovirus

When infected with reovirus ST3, strain Dearing, normal and transformed human lung fibroblasts exhibit differential sensitivities. Transformed cells (WI38 VA13 2RA) are destroyed within four days. In contrast, normal cells (WI38) maintain a productive infection for as long as two months. Attempts to examine the differences between these cells included the use of cDNA subtraction and a reovirus sigma 1 protein affinity chromatography column, both of which were hampered by technical difficulties. Two-dimensional gel electrophoresis revealed patterns of differential protein expression between infected and mock-infected normal and transformed cells. Visual comparison of Coomassie blue-stained gels revealed one protein which was present in uninfected normal cells but was missing in all other samples, as well as five proteins that were present in infected and mock-infected normal cells but were missing in both transformed cell samples. Autoradiography of 35S-labeled cell samples revealed an additional eleven proteins not seen with Coomassie staining. Further characterization of these proteins should uncover the mechanism of differential cell killing by reovirus.