Studies on the Specificity of Interferon

The antiviral effects of chick and mouse interferons on chick and mouse cells were studied. In both systems a small amount of antiviral activity was found in the heterologous assays which varied from approximately 1 to 10 % of the homologous antiviral effect. A difference in the uptake of interferon by homologous and heterologous cells was observed which only partly explained the relative species specificity of the antiviral action of the two interferons. Destruction of interferon by supernatants from homologous or heterologous cultures could not be shown. The slopes of the dose response curves of mouse or chick interferon seemed to be significantly different and were independent of the two cell strains employed