Stimulatory and inhibitory effects of adenovirus and SV 40 on various virus-cell systems

Abstract

Infection of mouse, rat, hamster, or chicken cells with adenovirus types 5 and 12, or SV40, caused inhibition of subsequent challenge with VSV, EMC and vaccinia viruses. This effect was most marked with adenovirus on mouse cells, where a transitory phase of stimulation was frequently demonstrated immediately after adenovirus infection. The inhibitory phase usually commenced 2--6 hours after infection and depended on infection with intact virions, although the intact adenovirus genome was not necessary. Binding of virus by antiserum did not prevent the inhibition, and inhibition could not be explained by differences in adsorption, interferon production, chromosome breakage, or the effect of soluble capsid antigens. After transformation with SV40, mouse ceils showed increased VSV sensitivity in distinction to acutely infected cells in which the challenge virus was inhibited. The implications of these studies in the evolution of the transformation process are discussed.