B-cell receptor recognizing Streptococcus pneumoniae serotype 7F capsular polysaccharide (BCR-Sp7F)

The B-cell receptor (BCR) recognizing Streptococcus pneumoniae serotype 7F capsular polysaccharide is a membrane-bound immunoglobulin on the surface of specific B-lymphocytes that identifies the unique antigenic epitopes of the 7F capsule. Serotype 7F is recognized as a highly invasive pneumococcal strain frequently associated with severe infections such as pneumonia, bacteremia, and meningitis. These receptors are the primary targets of pneumococcal vaccines, which aim to stimulate the expansion of 7F-specific B-cell clones. Conjugate vaccines, such as PCV13 and PCV20, utilize the 7F polysaccharide linked to a carrier protein to engage these BCRs and recruit T-cell help, ensuring the development of high-affinity IgG antibodies and long-lived memory B cells. The activation of these receptors is crucial for establishing protective humoral immunity, as the resulting antibodies facilitate the opsonization and subsequent destruction of the bacteria by the host's immune system. Monitoring the response of these receptors and their secreted antibody products is a standard method for evaluating vaccine efficacy and population-level immunity.

Other names

Anti-7F pneumococcal B-cell receptorB-cell receptor for Streptococcus pneumoniae type 7F CPSAnti-Pn7F BCRStreptococcus pneumoniae serotype 7F-specific B-cell receptor

Vaccine-delivered capsular polysaccharide antigens bind to and cross-link these specific B-cell receptors, initiating signal transduction that leads to B-cell proliferation, isotype switching (in the presence of T-cell help from conjugate vaccines), and differentiation into memory B cells and plasma cells. The resulting secreted antibodies opsonize serotype 7F pneumococci for phagocytic clearance.