Human Interferon and Cell Growth Inhibition. VI. Effect of Different Inhibitors of Cellular Functions on Interferon Activities

The effects of actinomycin D, ouabain, and cholera toxin on the activities of human alpha interferon (HuIFN-γ) and two components isolated from HuIFN-γ were studied in different human cell lines. Antiviral activity as well as cell growth inhibition by the antiviral component were suppressed by the three inhibitors. Cell growth inhibition associated with the anticellular component was not affected. The results indicate two different mechanisms for growth regulation by IFN preparations. It is suggested that growth inhibition by the antiviral component is a consequence of the antiviral activity and that the anticellular component has a completely different mechanism of action.