Immune-enhanced Phagocytosis of Neisseria gonorrhoeae by Macrophages: Characterization of the Major Antigens to which Opsonins are Directed

Publisher Website
Google Scholar
Abstract
Antisera were prepared in rabbits against whole organisms of colony type 1 N. gonorrhoeae strains F62 and B (from gonococcal urethritis) and 7122 (a strain typical of those associated with disseminated gonococcal infection), and against purified outer membrane components from the same strains including pili and principal outer membrane protein. Antibody levels to pili, principal outer membrane protein and lipopolysaccharide were determined using a quantitative enzyme-linked immunosorbent assay. Each antiserum was heat-inactivated and tested opsonic activity in a quantitative assay of phagocytosis. Each whole-organism antiserum was opsonic for its homologous strain, and this immune-enhanced phagocytosis was decreased by adsorption with homologous purified outer membrane components: pili .mchgt. lipopolysaccharide .mchgt. prinicpal outer membrane protein. Opsonic activity was approximately equal for antiserum to purified pili and antiserum to the whole organisms for each of the 3 strains, and purified antibody to pili was highly opsonic. The F(ab'')2 fragments of antibody to pili were not opsonic, indicating a role for the Fc receptor on the phagocyte membrane in immune-enhanced phagocytosis of gonococci.