Capsular polysaccharide of Streptococcus pneumoniae serotype 4 (CPS4)

The capsular polysaccharide of Streptococcus pneumoniae serotype 4 is a complex carbohydrate structure that forms the outermost layer of the bacterium. It serves as a primary virulence factor by shielding the pathogen from the host's immune system, specifically by inhibiting opsonophagocytosis by neutrophils and macrophages [1.2.1, 1.4.1]. This serotype is a significant cause of invasive pneumococcal diseases, including pneumonia, meningitis, and bacteremia, particularly in children and high-risk adults [1.3.1, 1.4.4]. As a key antigenic component, it is included in most multivalent pneumococcal vaccines, such as PCV13, PCV20, and PPSV23, to elicit protective antibody responses [1.3.2, 1.5.3]. Vaccination induces the production of serotype-specific IgG antibodies that opsonize the bacteria, facilitating their destruction and reducing both disease incidence and nasopharyngeal carriage [1.3.1, 1.3.3]. These immune responses are critical for preventing both localized and systemic infections caused by this specific pneumococcal strain [1.4.4].

Other names

Pneumococcal polysaccharide serotype 4Streptococcus pneumoniae type 4 capsular polysaccharide antigenST4 CPSPn4PS

Induction of active immunity through the production of serotype-specific opsonophagocytic antibodies.