The role of spontaneous DNA damage in the radiosensitivity of thymus lymphocytes

The most radiosensitive thymus cortical lymphocytes are highly sensitive to inhibitors of repair of spontaneous DNA lesions known by endonucleases: this is indicative of different level of injury to cells. The preincubation of cells with chemical inductors of differentiation increases the number of spontaneous lesions in them. The preincubation of thymocytes with concanavalin A removes almost completely the differences in the level of injury.