Molecular species occurring in naturally induced interferon alpha

Human interferon alpha (HuIFN-alpha) preparations induced in human peripheral white blood cells by Sendai virus were analyzed for activity after ultrafiltration, ion exchange, metal ion chromatography and isoelectrofocusing. It was found that HuIFN-alpha forms complexes with various physical properties and activities. Some of the IFN-alpha copurify with high molecular weight complexes. However, the low molecular weight fraction represent bulk of IFN activity. In isoelectrofocusing experiments, the former corresponds to IFN-alpha which possesses high pI (pH regions 8.5-10.5). An additional form of IFN-alpha are not complexed and possess a pI of 5.5-7.0. Our nIFN-alpha preparation preserve many of natural IFN isospecies and may have higher therapeutic value than the recombinant IFN-alpha preparations.