Preparation and properties of monoclonal antibodies against murine interferon-β

Wistar rats were immunized with total crude, poly(I) poly(C)-induced mouse L cell interferon. Spleen cells of one rat producing serum antibodies against Mu IFNβ were fused with the NS-1 mouse myeloma cell line using standard procedures. Two hybridomas secreting IgG antibodies to Mu IFNβ were selected using a direct neutralization assay. The hybridomas were cloned by limiting dilution. One clone (2E8B3) was propagated in nude mice. The immunoglobulin fraction was isolated from sera of mice transplanted with this clone and immobilized by coupling to CNBr-activated Sepharose. Affinity chromatography analysis showed that a column prepared from this material was capable of complete binding of Mu IFNβ All Mu IFNa activity was present in the flow through fraction. Analysis of a [ 35S]methionine-radiolabeled L cell interferon preparation over the monoclonal anti-Mu IFNβ agarose column resulted in a complete purification of Mu IFNβ SDS-polyacrylamide gel electrophoresis of the purified material showed that poly(I) · poly(C)-induced mouse L cell interferon contains one Mu IFNβ species with a molecular weight of 32,000 to 34,000.