We have characterized the functional properties of four highly purified recombinant human class I α-interferon subtypes whose biological activities have not been described previously. We selected biological and biochemical activities that may discriminate between different functions of these molecules. We found that the α subtypes could be discriminated only by antiviral-host range specificity and natural killer cell activation. Differences in their antiproliferative activity were cell line dependent. Competitive binding, antiproliferative activity in agar, enhancement of expression of HLA-ABC, elevation of 2′-5′-oligoadenylate synthetase levels and enhancement of phosphorylation of the Mr 69,000 protein kinase did not allow discrimination among the αI subtypes on the tested cell lines.
This work was funded by a joint program between Cetus Corporation and Shell Oil Corporation.