Limited local and systemic antibody responses to Neisseria gonorrhoeae during uncomplicated genital infections

Repeated infections with Neisseria gonorrhoeae are common among patients at tending sexually transmitted disease clinics. We examined whether previous infections or site of infection altered the local and systemic antigonococc al antibody levels in males and females. Antibodies against N. gonorrhoeae MS11 and the patients' homologous infecting isolates were measured by enzym e-linked immunosorbent assay. In general, the local and systemic immune res ponses to gonococci were extremely modest. There was a slight increase in s erum immunoglobulin G (IgG) against the MS11 strain and the homologous isol ates in infected males. Levels of serum IgA1 antibodies against MS11 were s lightly higher in infected than in uninfected females. A history of previou s infections with N. gonorrhoeae did not alter the antibody levels in patie nts with a current infection, suggesting that immunological memory is not i nduced by uncomplicated gonococcal infections. Antibody responses to infect ed subjects' homologous isolates were observed in cervical mucus; IgA1 leve ls increased while IgG levels decreased. The decline in mucosal IgG against the homologous isolates was less common in subjects having both rectal and cervical infections; otherwise, no effect of rectal involvement was observ ed. The absence of substantially higher antibody levels to gonococci where there is infection at a site known to contain organized lymphoid tissue sug gests that the low levels of responses to uncomplicated infections may not be due simply to an absence of inductive sites in the genital tract. We pro pose that in addition to its potential ability to avoid the effects of an i mmune response, N. gonorrhoeae does not elicit strong humoral immune respon ses during uncomplicated genital infections.