Meningococcal serogroup C capsular polysaccharide (MenC CPS)

The Meningococcal serogroup C capsular polysaccharide is a critical virulence factor of Neisseria meningitidis serogroup C, composed of repeating units of α-2,9-linked N-acetylneuraminic acid (sialic acid) (PubMed: 11511294). This polysaccharide forms a protective outer layer that allows the bacterium to evade the host's innate immune system by inhibiting opsonophagocytosis and preventing complement-mediated lysis (PubMed: 11511294). In the context of pharmacology, it serves as the primary antigen in both plain polysaccharide and protein-conjugated vaccines designed to prevent invasive meningococcal disease. Conjugation to carrier proteins, such as CRM197 or tetanus toxoid, enhances the immunogenicity of the polysaccharide by recruiting T-cell help and inducing long-term immunological memory, which is essential for protection in infants (PubMed: 12165081). Targeting this molecule through vaccination has successfully led to a significant global reduction in the incidence of meningitis and septicemia caused by serogroup C strains (StatPearls: NBK534827). Monitoring of vaccine efficacy is typically performed by measuring serum bactericidal antibody (SBA) titers, which correlate with clinical protection.

Other names

Neisseria meningitidis serogroup C capsular polysaccharideα-2,9-linked N-acetylneuraminic acid polymerMenC polysaccharideGroup C meningococcal polysaccharideMeningococcal group C antigen

Induction of a humoral immune response resulting in the production of capsular-specific bactericidal antibodies (IgG) that facilitate complement-mediated lysis and opsonophagocytosis of Neisseria meningitidis serogroup C.