A COMPARISON OF HUMAN AND MURINE MONOCLONAL IGGS SPECIFIC FOR THE P1.7 PORA PROTEIN OF NEISSERIA-MENINGITIDIS

Monoclonal human IgG SS269 reacts with Neisseria meningitidis expressi ng the P1.7 PorA protein and with linear peptides containing NGGAS, wh ich accounts for the P1.7 specificity. Murine monoclonal antibody to P 1.7 reacts with peptides containing the overlapping epitope, ASGQ. The human and murine antibodies have similar affinities. The low avidity human antibody is very inefficient at stimulating complement-mediated bactericidal killing while the high avidity murine antibody efficientl y kills bacteria. However, efficient opsonophagocytosis was mediated e ven at low concentrations of the human body antibody and in the absenc e of complement, suggesting that low avidity antibodies might be prote ctive against disease.