Heterocomplexes of human interferon and immunoglobulins: formation and properties.

To form heterocomplexes, human diploid fibroblast interferon was reacted with an excess of human immunoglobulin in the presence of an optimal concentration of glutaraldehyde. There was virtually no loss of interferon activity due to this treatment and the resulting heterocomplexes possessed the biological properties of both native interferon and immunoglobulin molecules. The apparent molecular weights determined by gel electrophoresis in the presence of sodium dodecyl sulfate were 20,000 for native interferon and 0.5 to 1 X 10(6) for the heterocomplex. Native interferon injected into mice intramuscularly had a serum half life of about 5 hours. However, serum interferon was not detected in mice receiving a similar dose of the heterocomplex.