Neisseria meningitidis group C capsular polysaccharide-specific B cell receptor

The Neisseria meningitidis group C capsular polysaccharide-specific B cell receptor is the primary immunological target for vaccines designed to prevent serogroup C meningococcal disease (NIH, 2024). This receptor, expressed on the surface of specific B cell clones, recognizes the alpha(2->9)-linked sialic acid homopolymer that constitutes the MenC capsule (NIH, 2007). In the context of conjugate vaccines, the BCR facilitates the uptake of the polysaccharide-protein complex, leading to the activation of T cell-dependent immune pathways (ClinicalTrials.gov, 2016). This process is crucial for overcoming the limitations of pure polysaccharide antigens, which are poorly immunogenic in infants and fail to induce immunological memory (NIH, 2018). By engaging T cell help, these pathways promote the production of high-affinity bactericidal IgG antibodies and the establishment of long-term protection through memory B cells (The Scientist, 2025). The interaction between the BCR and the vaccine conjugate is the initiating step in the formation of germinal centers where B cell maturation occurs (NIH, 2018). Consequently, this target is central to the efficacy of modern glycoconjugate vaccines like Menjugate and NeisVac-C (NIH, 2012). Monitoring the immune response to this target typically involves measuring serum bactericidal activity (SBA), which is the validated surrogate marker of protection (Vaccine, 2009).

Other names

Meningococcal group C polysaccharide-specific B cell receptorMenC-specific BCRB cell receptor for alpha(2->9)-linked sialic acidMenC capsular polysaccharide-specific B cell receptor

The vaccine's polysaccharide moiety binds to the specific B cell receptor (BCR), triggering internalization of the polysaccharide-protein conjugate (ClinicalTrials.gov, 2016). The carrier protein is then processed and its peptides are presented via MHC class II to CD4+ T follicular helper cells (NIH, 2018). This T cell-dependent pathway provides the necessary signals, such as CD40L and cytokines (IL-4, IL-21), for B cell proliferation, isotype switching to IgG, affinity maturation, and the generation of long-lived memory B cells and plasma cells (The Scientist, 2025).