Multiple biological activities of homogeneous human alpha interferon.

To identify the active molecule in human alpha interferon preparations, we performed several studies, using both partially purified interferon and homogeneous interferon. Our results indicated that there is little difference between the partially purified and the homogeneous interferon preparations in terms of antiviral activity, inhibition of deoxyribonucleic acid synthesis in human neoplastic cells, and enhancement of human natural killer cell activity.