Host Cell Reactivation of Ultraviolet Light Irradiated Adenovirus 5 in Fibroblasts from Patients with Cockayne Syndrome

Host cell reactivation of plaque-forming ability of ultraviolet light (UV)-irradiated adenovirus 5 was compared between skin fibroblasts derived from 6 unrelated patients with Cockayne syndrome (CS) and those from normal donors. UV survivals of adenovirus were determined with two different virus stocks, one prepared by infecting to HeLa cells and the other prepared from hamster BHK cells. For both of these virus stocks UV survival curves obtained using CS cells showed two components with an initial sensitive portion followed by a component having almost normal sensitivity. This made a marked contrast to the single-hit inactivation curves obtained with normal cells. Consequently, at low UV dose ranges, CS cells were 2-3 times less able to reactivate the UV-inactivated adenovirus than normal cells. These results further support our hypothesis that CS cells may be partially defective in excision repair of damaged DNA.