Pneumococcal capsular polysaccharide serotype 20 (CPS20)

Pneumococcal capsular polysaccharide serotype 20 is a complex carbohydrate polymer that constitutes the protective outer capsule of Streptococcus pneumoniae serotype 20 (FDA, 2021). This polysaccharide is a critical virulence factor that allows the bacterium to evade the host immune system by inhibiting phagocytosis (CDC, 2022). In medical therapeutics, it serves as a key antigen in polyvalent vaccines, such as the 20-valent pneumococcal conjugate vaccine (PCV20) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) (NIH, 2023). When introduced into the human body, the immune system recognizes the polysaccharide and generates serotype-specific antibodies (PubMed, 2021). These antibodies bind to the capsule of invading bacteria, marking them for destruction by immune cells through a process known as opsonophagocytosis (FDA, 2021). This target is essential for preventing invasive pneumococcal diseases, including pneumonia, meningitis, and febrile bacteremia, particularly in vulnerable populations like children and the elderly (CDC, 2022).

Other names

Streptococcus pneumoniae serotype 20 capsular polysaccharidePneumococcal polysaccharide serotype 20CPS20Serotype 20 pneumococcal antigen

Induction of active humoral immunity through the production of serotype-specific IgG antibodies that facilitate opsonophagocytosis of Streptococcus pneumoniae serotype 20 (FDA, 2021; CDC, 2022).