[Biological characteristics of a repressor of interferon production].

The data on the properties of the interferon production protein repressor are presented. It was isolated from the chick embryo fibroblasts in the state of hyperreactivity to repeated induction of poly (ri) poly (rC). The repressor activity amounted to 2048 IIU/ml. The repressor was thermoresistant and stable to pH 2.0-8.0. A pronounced interferon inhibitory effect of the repressor was observed after 20 minutes of its contact with the cells at a temperature of 37 degrees C. Its half-life was 10 hours. The repressor similarity with homologous interferon was noted.