Pneumococcal capsular polysaccharide serotype 5 (CPS5)

Pneumococcal capsular polysaccharide serotype 5 is a complex carbohydrate polymer that constitutes the protective outer capsule of Streptococcus pneumoniae serotype 5 (PubMed: 2992431). This polysaccharide is a major virulence factor, enabling the bacterium to evade the host's innate immune response by inhibiting opsonophagocytosis and complement-mediated killing (PMC4028116). Serotype 5 is a significant cause of invasive pneumococcal disease (IPD), including pneumonia, bacteremia, and meningitis, especially in pediatric and elderly populations (PMC4354531). It is a key component in several licensed pneumococcal vaccines, where it acts as an antigen to stimulate the production of protective antibodies (PubMed: 24145569). In conjugate vaccines, the polysaccharide is linked to a carrier protein to enhance immunogenicity and induce long-term immunological memory (PMC4028116). Monitoring of this target is essential for assessing vaccine efficacy and tracking serotype replacement in epidemiological studies (PubMed: 19526101).

Other names

Serotype 5 capsular polysaccharidePnCP5Streptococcus pneumoniae type 5 capsular polysaccharideS5 polysaccharidePneumococcal polysaccharide serotype 5Type 5 pneumococcal polysaccharideS5

Vaccines containing this polysaccharide induce the production of serotype-specific antibodies (IgG and IgM) that bind to the bacterial capsule, facilitating opsonophagocytosis and subsequent clearance by the host's immune system (PMC4028116, PubMed: 24145569).