B cell receptors recognizing capsular polysaccharide epitopes of nine Streptococcus pneumoniae serotypes (BCR-PnCPS9)

The target refers to the specific repertoire of B-cell receptors (BCRs) on the surface of B lymphocytes that bind to the capsular polysaccharides (CPS) of nine Streptococcus pneumoniae serotypes (1, 4, 5, 6B, 9V, 14, 18C, 19F, and 23F). These BCRs are the primary biological sensors for the antigens delivered by the 9-valent pneumococcal conjugate vaccine (PCV9). Upon engagement with these polysaccharide epitopes, the BCRs initiate intracellular signaling cascades, such as the Bruton's tyrosine kinase (Btk) pathway, which lead to B-cell activation, clonal expansion, and differentiation into memory B cells and antibody-secreting plasma cells. The resulting serotype-specific antibodies (IgG and IgM) provide protective immunity by opsonizing the bacteria for phagocytic clearance and activating the complement system. This target is critical for preventing invasive pneumococcal diseases, including pneumonia, meningitis, and bacteremia, particularly in vulnerable populations like infants and the elderly. The development of vaccines targeting these BCRs aims to provide broad protection against the most prevalent and virulent serotypes of the pathogen.

Other names

B-cell receptor and antibody recognizing Streptococcus pneumoniae polysaccharide antigenPneumococcal 9-valent vaccine targetBCRs recognizing S. pneumoniae CPS (1, 4, 5, 6B, 9V, 14, 18C, 19F, 23F)Pneumococcal polysaccharide B-cell receptors

Vaccine-induced B-cell receptor cross-linking and activation leading to the production of opsonizing antibodies