Reovirus-induced cytotoxicity and proinflammatory response compared with chemotherapy and irradiation. (a) Mel-888, Mel-624, Mewo and Skmel-28 cells were either left untreated or treated with 30 Gy irradiation, 1000 µg/ml dacarbazine (DTIC) or 10 PFU/cell reovirus. Cells were harvested 48 (i) or 72 h (ii) after treatment and stained with propidium iodide (PI) before fluorescence-activated cell sorting (FACS) acquisition. Cell death was determined as the proportion of cells staining positive for PI. (b) Melanoma cell lines were either left untreated, treated with 0.1, 1, 2.5, 5 or 10 PFU/cell reovirus, 100, 250, 500, 750, 1000 µg/ml DTIC or 1.875, 3.75, 7.5, 15 or 30 Gy irradiation. 48 h after treatment, supernatants were harvested and the production of interleukin (IL)-8 was determined by ELISA. (c) Mewo cells were treated as in (b) and the production of IL-6 was determined by ELISA. Data shown are representative of at least two independent experiments.