B-cell receptor (BCR) on capsular polysaccharide (CPS)-specific B cells (BCR (CPS-specific))

The B-cell receptor (BCR) on capsular polysaccharide (CPS)-specific B cells is a specialized membrane-bound immunoglobulin that recognizes and binds to the complex carbohydrate structures forming the protective capsules of various bacteria (1). This receptor is the fundamental unit for initiating the adaptive immune response against pathogens such as Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis (2). When a CPS antigen or a glycoconjugate vaccine binds to the BCR, it triggers a signaling cascade involving the CD79a/b subunits, leading to B-cell activation and differentiation (3). These antibodies are essential for opsonizing encapsulated bacteria, thereby facilitating their clearance by the host's phagocytic cells (4). In clinical practice, these BCRs are the primary targets for both polysaccharide and conjugate vaccines, which are designed to elicit high-affinity antibody responses and long-term immunological memory (5). The diversity and affinity of the BCR repertoire for different CPS serotypes are critical determinants of vaccine efficacy and the prevention of invasive bacterial diseases (6).

Other names

Capsular polysaccharide-specific B-cell receptorCPS-binding BCRAnti-CPS B-cell receptorPolysaccharide-specific B-cell receptor

Vaccine antigens bind to and cross-link the BCR on specific B cells, initiating signal transduction that leads to B-cell activation, proliferation, and differentiation into antibody-secreting plasma cells.