Antigenic determinants of influenza virus hemagglutinin. III. Competitive binding of antibodies directed against 'common' and 'strain-specific' antigenic determinants of A/Memphis/72 hemagglutinin

Abstract

Immunoglobulin G directed against the hemagglutinin (HA) of influenza virus A/Memphis/102/72 (H3N2) was adsorbed with either of two related viruses, A/Port Chalmers/73 (H3N2) or A/Papua New Guinea/75 (H3N2) to fractionate the antibody into 'strain-specific' ('specific') and 'cross-reactive' ('common') populations. These IgG preparations were tested with use of a solid-phase radioimmunoassay for their ability to compete with one another in binding to the antigenic determinants of Memphis HA. Their binding avidities were also determined. It was found that anti-'specific' and anti-'common' IgG preparations competed with each other for the antigenic regions on Memphis HA. In addition, the assign..