B cell receptor specific for Streptococcus pneumoniae type 14 capsular polysaccharide (BCR-PPS14)

The B cell receptor (BCR) specific for Streptococcus pneumoniae type 14 capsular polysaccharide (PPS14) is a membrane-bound immunoglobulin that plays a pivotal role in the host's adaptive immune response against pneumococcal infections (Pollard et al., 2009, Nature Reviews Immunology). Serotype 14 is historically one of the most prevalent causes of invasive pneumococcal disease (IPD) in children worldwide (Hausdorff et al., 2000, Clinical Infectious Diseases). The BCR recognizes the specific tetrasaccharide repeating unit of the PPS14 capsule, which consists of glucose, galactose, and N-acetylglucosamine residues (Kolkman et al., 1997, Biochemistry). Engagement of this receptor by the polysaccharide antigen, particularly when presented in a conjugate form with a carrier protein like CRM197, induces B cell activation, proliferation, and differentiation into memory B cells and plasma cells (Clutterbuck et al., 2012, Science Translational Medicine). This process results in the production of high-affinity IgG antibodies that facilitate the opsonophagocytic killing of the bacteria by host phagocytes (Grabenstein & Musey, 2014, Vaccine). Consequently, this BCR is the primary immunological target for various pneumococcal vaccines, including PCV13 and PPSV23, which aim to elicit protective immunity and reduce the incidence of pneumonia and meningitis.

Other names

Anti-PPS14 B cell receptorStreptococcus pneumoniae serotype 14 capsular polysaccharide-specific B cell receptorPneumococcal polysaccharide type 14-specific BCRBCR specific for PPS14

The target acts as the primary recognition site for pneumococcal antigens; binding of the capsular polysaccharide (or conjugate) to the BCR initiates signal transduction pathways that lead to B cell proliferation and the secretion of serotype-specific antibodies which facilitate bacterial opsonophagocytosis (Pollard et al., 2009).