Responses to interferon of LM cells growing continuously in the absence of serum and exogenous lipids.

Mouse fibroblast LM cells growing continuously in the absence of serum and exogenous lipids are proposed as a model for studying interferon action. Several of its activities, namely the inhibition of virus and cell growth, and the increased cytotoxicity of poly(rI) X poly(rC), are shown to be potentiated in such conditions. Since cells cultured under these conditions are devoid of precursors of prostaglandin biosynthesis, the data suggest that none of the three effects of interferon depends on active prostaglandin synthesis.