Effect of antipain on radiation induction of endogenous type-C virus from mouse cells in vitro.

Xenotropic murine type-C virus was induced after X-ray or UV light irradiation of K-Balb cells. The induction was markedly suppressed by postirradiation treatment of the cells with antipain, a protease inhibitor of microbial origin. Virus expression was unaffected when the cells were treated with halogenated pyrimidines.