B-cell receptor specific for Streptococcus pneumoniae capsular polysaccharide (BCR-SpCPS) (BCR-SpCPS)

B-cell receptor specific for Streptococcus pneumoniae capsular polysaccharide (BCR-SpCPS) is a membrane-bound immunoglobulin on the surface of B lymphocytes that recognizes the carbohydrate capsule of the pneumococcus (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3070672/). This capsule is the primary virulence factor of Streptococcus pneumoniae, and its recognition by the BCR is the first step in the induction of a protective immune response (https://pubmed.ncbi.nlm.nih.gov/22517866/). Upon binding to specific polysaccharide epitopes, the BCR initiates a signaling cascade involving kinases like Syk and Lyn, which leads to B-cell activation, proliferation, and differentiation into plasma cells (https://www.uniprot.org/uniprotkb/P11912/entry; https://www.nature.com/articles/nri3200). These plasma cells secrete antibodies that opsonize the bacteria, allowing for their clearance by phagocytes (https://www.cdc.gov/vaccines/pubs/pinkbook/pneumo.html). This receptor is the primary target for both pneumococcal polysaccharide vaccines (PPSV) and pneumococcal conjugate vaccines (PCV), which aim to elicit high-affinity IgG antibodies and establish immunological memory (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4923267/). In clinical settings, the effectiveness of targeting these receptors is measured by antibody titers and opsonophagocytic activity, which correlate with protection against invasive diseases like pneumonia and meningitis (https://www.fda.gov/vaccines-blood-biologics/vaccines/prevnar-20).

Other names

Pneumococcal polysaccharide-specific B-cell receptorAnti-CPS BCRAnti-PnPS BCRStreptococcus pneumoniae capsular polysaccharide-binding B-cell receptor

Antigen-mediated B-cell receptor cross-linking and activation leading to clonal expansion and antibody secretion.