Monoclonal antibody to a major glycoprotein immunogen mediates differential complement-independent lysis of Trichomonas vaginalis

Abstract

An immunoglobulin G type 2a (IgG2a) monoclonal antibody (MAb), designated C20A3, which reacts with a highly immunogenic trichomonad membrane glycoprotein (~ 270,000 daltons), produced complement-independent cytolysis of Trichomonas vaginalis organisms. Time- and temperature-dependent lysis of parasites was observed following incubation of washed, live T. vaginalis with certain concentrations of C20A3 IgG. Differential killing of trichomonal isolates and clones of a given isolate by C20A3 was dependent on the presence of the glycoprotein antigen on the parasite surface.