The preparation of antibodies directed against human immune interferon.

Antisera against human immune interferon (HuIFN-gamma) were prepared by immunization of rabbits and a goat with antigens of different degrees of purity: a) crude supernatant from concanavalin A-stimulated human leukocytes; b) a preparation partially purified by adsorption to controlled pore glass; and c) pooled fractions (molecular weight - 45,000) obtained by gel filtration and corresponding to the peak of HuIFN-gamma. Antisera with a relatively high titer were obtained in animals immunized with the latter two antigens. The sera were specific for HuIFN-gamma in that they failed to neutralize preparations of HuIFN-alpha and and HuIFN-beta. From the time course of the antibody titers in each animal it seemed that frequent boosters within a short time interval led to a decrease rather than an increase in neutralizing activity of the sera.