Neisseria meningitidis serogroup A polysaccharide conjugate (MenA-PS conjugate; MenAfriVac)

The Neisseria meningitidis serogroup A polysaccharide conjugate is a vaccine antigen consisting of the capsular polysaccharide from serogroup A N. meningitidis covalently linked to a carrier protein (e.g., tetanus toxoid). Its introduction in sub-Saharan Africa resulted in dramatic declines in MenA meningitis cases through mass vaccination, providing herd immunity and robust protection. The conjugate improves immunogenicity over plain polysaccharide vaccines and enables persistent antibody responses, addressing previous epidemic challenges in the region. The polysaccharide capsule is the main virulence factor of N. meningitidis; conjugating it to a protein carrier allows for T-cell dependent immune responses and long-lasting immunity. MenAfriVac and related vaccines have virtually eliminated serogroup A epidemics in the African meningitis belt. Ongoing development includes multivalent conjugate vaccines covering other serogroups, such as NmCV-5. This entity should not be considered a therapeutic target in the conventional sense, but rather a vaccine antigen engineered to induce immunity against a specific bacterial serogroup. If you require structured data for pharmaceutical or biological databases, categorize it under "vaccine antigen," not "molecular target."

Other names

MenAfriVacPsA-TTMenA conjugate vaccineMenACV

Vaccine mechanism—induces immune response by presenting capsular polysaccharide (a key virulence factor) conjugated to a protein carrier, stimulating the production of serum bactericidal antibodies