title: Meningococcal omp85 in detergent-extracted outer membrane vesicle vaccines induces high levels of non-functional antibodies in mice.
abstract: The vaccine potential of meningococcal Omp85 was studied by comparing the immune responses of genetically modified deoxycholate-extracted outer membrane vesicles, expressing five-fold higher levels of Omp85, with wild-type vesicles. Groups (n = 6-12) of inbred and outbred mouse strains (Balb/c, C57BL/6, OFI and NMRI) were immunized with the two vaccines, and the induced antibody levels and bactericidal and opsonic activities measured. Except for Balb/c mice, which were low responders, the genetically modified vaccine raised high Omp85 antibody levels in all mouse strains. In comparison, the wild-type vaccine gave lower antibody levels, but NMRI mice responded to this vaccine with the same high levels as the modified vaccine in the other strains. Although the vaccines induced strain-dependent Omp85 antibody responses, the mouse strains showed high and similar serum bactericidal titres. Titres were negligible with heterologous or PorA-negative meningococcal target strains, demonstrating the presence of the dominant bactericidal PorA antibodies. The two vaccines induced the same opsonic titres. Thus, the genetically modified vaccine with high Omp85 antibody levels and the wild-type vaccine induced the same levels of functional activities related to protection against meningococcal disease, suggesting that meningococcal Omp85 is a less attractive vaccine antigen.
authors.affiliation: Division of Infectious Disease Control, Department of Bacteriology and Immunology, Norwegian Institute of Public Health, Oslo, Norway. elisabeth.wedege@fhi.no
authors.forename: E
authors.initials: E
authors.lastname: Wedege
authors.forename: K
authors.initials: K
authors.lastname: Lie
authors.forename: K
authors.initials: K
authors.lastname: Bolstad
authors.forename: V E
authors.initials: VE
authors.lastname: Weynants
authors.forename: A
authors.initials: A
authors.lastname: Halstensen
authors.forename: T K
authors.initials: TK
authors.lastname: Herstad
authors.forename: J
authors.initials: J
authors.lastname: Kreutzberger
authors.forename: L
authors.initials: L
authors.lastname: Nome
authors.forename: L M
authors.initials: LM
authors.lastname: Naess
authors.forename: A
authors.initials: A
authors.lastname: Aase
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology*; D000942:Antigens, Bacterial / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D015151:Immunoblotting; D022401:Meningococcal Vaccines / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D022401:Meningococcal Vaccines; C115176:Omp85 protein, Neisseria; D011994:Recombinant Proteins