74] Preparation and absorption of antiserum against mouse L cell interferon

Abstract

This chapter describes the production and absorption of sheep antiserum to live Newcastle disease virus (NDV) induced mouse L cell interferon. Antibody titers to known contaminants found in the interferon preparation are measured by a passive hemagglutination test as detailed. Three contaminants of NDV-induced mouse L cell interferon are chosen to monitor the success of the absorption procedure: (a) egg albumin, since the inducer virus is produced in embryonated eggs, (b) bovine serum albumin, present in the serum used to culture the mouse cells, and (c) L cell extract, a mixture of antigens from sonicated mouse L cells. The anti-mouse interferon serum is absorbed by the same procedure described for the absorption of anti-human leukocyte interferon serum. As in the case of the absorption of antiserum to human leukocyte interferon, the unbound material also had to be supplemented with egg albumin in order to remove a large portion of the antibodies to this contaminant. The level of antibodies to the test contaminant antigens that remained after absorption are reduced to background titers found in control serum taken prior to immunization.