Meningococcal capsular polysaccharide (CPS)

Meningococcal capsular polysaccharide is a major virulence factor and surface component of the bacterium Neisseria meningitidis, which is responsible for life-threatening invasive diseases such as meningitis and septicemia (Stephens et al., 2007, The Lancet). This polysaccharide layer acts as a protective shield, allowing the pathogen to evade the host's innate immune system by resisting opsonophagocytosis and complement-mediated lysis (Ram et al., 2010, FEBS Letters). In clinical medicine, these polysaccharides serve as the primary antigens for vaccines, categorized into different serogroups such as A, C, W-135, and Y based on their chemical structure (Harrison et al., 2009, Vaccine). Modern conjugate vaccines link these polysaccharides to carrier proteins to transform the immune response from T-cell independent to T-cell dependent, thereby inducing high-affinity antibodies and long-term immunological memory (Pollard et al., 2009, Nature Reviews Immunology). The interaction between the vaccine-induced antibodies and the polysaccharide target leads to the destruction of the bacteria upon exposure, preventing systemic infection. Consequently, this molecule is a critical target for public health interventions aimed at reducing the global burden of meningococcal disease.

Other names

Neisseria meningitidis capsular polysaccharideMeningococcal antigenBacterial capsular polysaccharideGroup A/C/W/Y polysaccharide

Induction of protective serum bactericidal antibodies (SBA) that target the capsule for complement-mediated lysis and opsonophagocytosis.