Neisseria meningitidis serogroup W capsular polysaccharide (MenW PS) (MenW PS)

Neisseria meningitidis serogroup W capsular polysaccharide is the primary antigenic target for vaccines protecting against serogroup W meningococcal disease. It is a virulence factor composed of repeating units of sialic acid and galactose that allows the bacterium to evade the host immune system by preventing complement-mediated lysis (Harrison et al., 2013, Journal of Clinical Microbiology). While the polysaccharide itself is the target of the immune response, it is often administered as a conjugate with a carrier protein like CRM197 to enhance immunogenicity. CRM197 is a non-toxic mutant of diphtheria toxin that converts the polysaccharide into a T-cell dependent antigen, enabling the induction of high-affinity antibodies and long-term immunological memory (Shinefield, 2010, Vaccine). Therapeutic intervention via vaccination aims to generate serum bactericidal antibodies that facilitate the destruction of the pathogen (Pollard et al., 2009, Nature Reviews Immunology). These antibodies promote opsonophagocytosis and complement-mediated killing, providing protection against invasive infections such as meningitis and septicemia (Borrow et al., 2005, Vaccine).

Other names

Neisseria meningitidis serogroup W capsular polysaccharide–CRM197 conjugateMenW-135 polysaccharideMeningococcal group W antigenW-135 capsular polysaccharideMenW PS

Induction of a T-cell dependent immune response where the polysaccharide-protein conjugate is processed by B-cells and presented to T-helper cells, leading to the production of high-affinity bactericidal IgG antibodies and memory B-cells (Pichichero, 2013, Human Vaccines & Immunotherapeutics).