Infection and Immunity
Biology | Life Sciences
Neisseria meningitidis serogroup B is a major cause of bacterial meningitis in younger populations. The available vaccines are based on outer membrane vesicles obtained from wild-type strains. In children less than 2 years old they confer protection only against strains expressing homologous PorA, a major, variable outer membrane protein (OMP). We genetically modified a strain in order to eliminate PorA and to overproduce one or several minor and conserved OMPs. Using a mouse model mimicking children's PorA-specific bactericidal activity, it was demonstrated that overproduction of more than one minor OMP is required to elicit antibodies able to induce complement-mediated killing of strains expressing heterologous PorA. It is concluded that a critical density of bactericidal antibodies needs to be reached at the surface of meningococci to induce complement-mediated killing. With minor OMPs, this threshold is reached when more than one antigen is targeted, and this allows cross-protection.
Weynants, Vincent E.; Feron, Christiane M.; Goraj, Karine K.; Bos, Martine P.; Denoeal, Philippe A.; Verlant, Vincent G.; Tommassen, Jan; Peak, Ian R. A.; Judd, Ralph C.; Jennings, Michael P.; and Poolman, Jan T., "Additive and Synergistic Bactericidal Activity of Antibodies Directed Against Minor Outer Membrane Proteins of Neisseria Meningitidis" (2007). Biological Sciences Faculty Publications. 51.