title: Anti-idiotype induced protection against Neisseria meningitidis serogroup C bacteremia.
abstract: We have developed a monoclonal anti-idiotypic antibody, designated 6F9, which acts as the surrogate image of the meningococcal group C capsular polysaccharide (MCP). Murine immunization with 6F9 results in a T-dependent anti-MCP antibody response. To examine the protective nature of the antibody response elicited by 6F9 we performed a series of live challenge studies using a murine model for meningococcal infection in which mice were iron dextran treated and challenged with 10 x LD50 of meningococcal group C strain 35E. Adult BALB/c mice immunized with 6F9 had a 100% survival and a significantly reduced level of bacteremia at 24 h. Mice immunized with MCP had an 80% survival rate, all survivors were bacteremic at 24 h. Neonatal mice primed within 24 h of birth and immunized at 4 weeks of age with 6F9 had a 100% survival and cleared their bacteremia by 8 h, which was significantly faster than the MCP primed and immunized mice. Neonatal mice primed with 6F9 and challenged at 5 weeks of age had a survival rate of 90% which was significantly higher than mice primed with MCP and the control group (60% and 50% survival, respectively). Mice primed at birth and immunized at 8 days had a 100% survival and 90% of these mice had sterile blood cultures by 8 h. Mice primed and immunized with MCP all remained bacteremic at 24 h. These data indicate that the anti-Id 6F9 which mimics the capsular polysaccharide of group C meningococci is capable of inducing protective immunity in immunologically mature as well as immature animals.
authors.affiliation: Department of Medicine, State University of New York, Buffalo 14215.
authors.forename: M A
authors.initials: MA
authors.lastname: Westerink
authors.forename: P C
authors.initials: PC
authors.lastname: Giardina
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000888:Antibodies, Anti-Idiotypic / Q000008:administration & dosage / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000008:administration & dosage / Q000276:immunology*; D016470:Bacteremia / Q000276:immunology* / Q000517:prevention & control; D004797:Enzyme-Linked Immunosorbent Assay; D007114:Immunization; D008585:Meningitis, Meningococcal / Q000276:immunology* / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C; D009345:Neisseria meningitidis / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000907:Antibodies, Bacterial; D011135:Polysaccharides, Bacterial; C037676:meningococcal group C polysaccharide