Pneumococcal capsular polysaccharide conjugated to carrier protein (PCV)

Pneumococcal capsular polysaccharide conjugated antigens are components of glycoconjugate vaccines where serotype-specific capsular polysaccharides from *Streptococcus pneumoniae* are covalently attached to carrier proteins (such as CRM197 or diphtheria toxoid). This design converts the polysaccharide antigen from a T cell-independent to a T cell-dependent antigen, enabling robust immunogenicity and protection against invasive infection, especially in young children and elderly populations. The polysaccharides themselves are major virulence factors of pneumococcus and exhibit extensive chemical and immunological diversity. These antigens are not molecular targets in the classic sense but are used as immunogens for prophylactic vaccination

Other names

Pneumococcal conjugate antigenPneumococcal conjugate vaccine antigenPneumococcal capsular polysaccharide conjugatePCV antigenGlycoconjugate vaccine antigen

Induces T cell-dependent immune responses by covalent linkage of bacterial capsular polysaccharides to protein carriers, allowing processing and presentation by antigen-presenting cells and B cells, stimulating the formation of germinal centers, high-affinity antibody production, and immunologic memory