Haemophilus influenzae type a capsular polysaccharide-specific B-cell receptor (Hia CPS-specific BCR)

The Haemophilus influenzae type a (Hia) capsular polysaccharide-specific B-cell receptor is a membrane-bound immunoglobulin complex found on the surface of B lymphocytes that specifically recognizes the Hia capsular polysaccharide (CPS), a critical virulence factor (Ulanova & Tsang, 2014). Binding of the CPS antigen—typically presented as a protein conjugate in vaccines—to this receptor initiates a signaling cascade that leads to B-cell activation, clonal expansion, and differentiation into antibody-secreting plasma cells and memory B cells (Cox et al., 2017). These antibodies provide protection by opsonizing the bacteria for phagocytosis and neutralizing its virulence, which is essential for preventing invasive diseases like meningitis and pneumonia (CDC, 2022). This receptor is the primary target for Hia conjugate vaccines currently under development, which aim to address the rising incidence of Hia infections in the post-Hib vaccine era (Shuel et al., 2021). Monitoring the activation of these receptors through anti-CPS IgG titers and serum bactericidal activity serves as a key measure of vaccine efficacy and patient immunity (Potts et al., 2019). The receptor's engagement is the first step in establishing long-term immunological memory against the Hia serotype.

Other names

Hia capsular polysaccharide-specific B-cell receptorB-cell receptor for Hia CPSHia-specific BCRHaemophilus influenzae type a CPS-specific B-cell receptor

The vaccine antigen binds to the B-cell receptor, initiating signal transduction that leads to B-cell differentiation into antibody-secreting plasma cells and memory B cells.