Neisseria meningitidis serogroup B outer membrane antigen (None standardized; sometimes referred collectively as "MenB OM antigens" or “OMV antigens” in vaccine contexts, but no single canonical abbreviation.)

Neisseria meningitidis serogroup B outer membrane antigens encompass a heterogeneous group of structurally diverse proteins and lipoproteins embedded in the bacterial outer membrane, primarily including PorA, fHbp, NadA, NHBA, and others. These antigens mediate critical biological functions such as host cell adhesion, immune evasion (including complement regulation), and nutrient transport. The OM antigens are central to the immunogenicity of OMV-based and recombinant protein vaccines (e.g., "Bexsero/4CMenB"), which induce antibody-mediated killing of N. meningitidis and provide protection against group B strains. While highly immunogenic, these antigens vary significantly between strains, and vaccine efficacy is thus largely strain-specific. OMV vaccines were developed due to safety risks with polysaccharide vaccines for MenB. The principal safety issues involve appropriate detoxification of LPS and risk for immune evasion due to antigenic diversity.

Other names

MenB outer membrane proteinsMenB OMPsMeningococcal group B OMV antigensOMV antigens (in vaccine literature; e.g., Bexsero antigens)PorA, PorB, NadA, NHBA, fHbp (names of key individual components)

Vaccine-induced antibody-mediated bactericidal activity (serum bactericidal antibodies targeting OMPs, especially "PorA", "fHbp", "NadA", "NHBA"); Inhibition of adhesins (preventing bacterial adherence/invasion); Complement activation (through immune response to exposed antigens)