Antiviral and cell growth inhibitory activities reside in the same glycoprotein of human fibroblast interferon.

Abstract

IT has been shown repeatedly that preparations of mouse interferon inhibit the growth of mouse cells in vitro1–4 In addition to inducing the antiviral state and inhibiting cell growth, preparations of mouse interferon stimulate interferon production by priming5, enhance phagocytic activity6, and potentiate in cells the toxic effect of double-strand ed RNA7. All attempts with preparations of mouse interferon to separate the antiviral activity from the non-antiviral activities have been unsuccessful3,5,8. With human interferon few experiments have been reported, although the data available indicate inhibition of growth by preparations of human leukocyte interferon9–11. It has been claimed that the antiviral and cell growth inhibitory activities of human leukocyte interferon reside in different molecules and can be separated from each other by certain methods of fractionation12. In a more recent report13, however, separation of the two activities could not be demonstrated even in drastic denaturing conditions. I have shown that both the antiviral and the cell growth inhibitory activity of human fibroblast interferon reside in the same glycoprotein.