Adjuvant and immunogenic properties of gonococcal R-type lipopolysaccharide in reaginic antibody formation in mice.

The ability of gonococcal R-type lipopolysaccharide (LPS) to function as an adjuvant and as an antigen in the formation of IgE and IgG1 antibody responses in mice was investigated. LPS failed to induce LPS-specific IgE or IgG1 under a variety of experimental conditions. LPS was capable of enhancing IgE and IgG1 antibody responses to gonococcal protein (ZAB), but its adjuvant effect was weaker than that of Al(OH)3. The LPS-induced anti-ZAB IgE antibody titers showed a cycling phenomenon with time, but the IgG1 response was delayed and peaked only once.