Enhanced activity of the macrophage-like cell line J774.1 following exposure to gamma radiation.

Exposure of the macrophage-like cell line J774.1 to 20 gray of cobalt-60 gamma radiation resulted in a block of tritiated thymidine incorporation, along with an increase in cell "activation," as assessed by increases in lysosomal enzyme and ectoenzyme content, PMA-induced H2O2 production, and NBT staining, ingestion of E(IgG), spreading, and membrane ruffling. These changes are evident within 1 day postradiation and peak at 4 days postradiation.