Monoclonal antibodies against the human interferon-gamma receptor(s)

Enriched human interferon-gamma (HuIFN-gamma) receptor preparations were obtained by affinity chromatography of non-ionic detergent solubilized COLO 205 cell membranes on immobilized recombinant HuIFN-gamma. The active fractions, identified by a competition ELISA, were used as the immunogen in a BALB/c mouse. Fusion of its splenocytes with myeloma cells yielded several hybrids secreting antibodies that inhibit the antiviral activity of HuIFN-gamma; the two most active ones were selected for further characterization. This blocking activity was restricted to both the human species and the gamma type of IFN. Affinity purification of cell membrane extracts on the immobilized monoclonal antibodies resulted in the visualization of a major protein band with an Mr of 90,000, which is in good agreement with the results obtained by other authors [Aguet M. and Merlin G. (1987) J. exp. Med. 165, 988-999; Novick D., Orchansky P., Revel M. and Rubinstein M. (1987) J. biol. Chem. 262, 8483-8487; Sheehan K. C. F., Calderon J. and Schreiber R. D. (1988) J. Immun. 140, 4231-4237].