B-cell receptor recognizing pneumococcal capsular polysaccharide serotype 22F

B-cell receptors (BCRs) and antibodies recognizing pneumococcal capsular polysaccharide serotype 22F are specialized proteins of the immune system that identify and neutralize Streptococcus pneumoniae bacteria carrying the 22F capsule. Serotype 22F has emerged as a leading cause of invasive pneumococcal disease (IPD) globally, often associated with high rates of antibiotic resistance and severe clinical outcomes like meningitis and sepsis (Source: CDC, Pneumococcal Disease Surveillance, 2023). When these BCRs encounter the 22F antigen, typically delivered via conjugate vaccines like PCV15 or PCV20, they initiate a signaling cascade that results in B-cell clonal expansion and the secretion of high-affinity IgG antibodies (Source: FDA, Vaxneuvance Prescribing Information, 2021). These antibodies bind to the bacterial surface, facilitating opsonophagocytosis by neutrophils and macrophages, which is the primary host defense mechanism against encapsulated pathogens (Source: PubMed, PMID: 34161334). Therapeutic strategies focus on inducing these specific antibodies to provide broad protection against the diverse range of pneumococcal serotypes. Clinical efficacy is often measured by the concentration of serotype-specific IgG and the functional ability of these antibodies to kill the bacteria in opsonophagocytic activity (OPA) assays (Source: Pfizer, Prevnar 20 Prescribing Information, 2021).

Other names

Anti-pneumococcal serotype 22F antibodyAnti-CPS22F B-cell receptorPneumococcal polysaccharide serotype 22F-specific immunoglobulin

The mechanism involves the induction of a humoral immune response where the vaccine's 22F polysaccharide antigen binds to specific B-cell receptors. This binding, in the presence of T-cell help (for conjugate vaccines), triggers B-cell proliferation and differentiation into plasma cells that secrete high-affinity IgG antibodies. These antibodies then bind to the 22F capsule of Streptococcus pneumoniae, facilitating opsonophagocytosis and bacterial killing by host immune cells (Source: PubMed, PMID: 34161334).