B-cell receptor signaling pathway (BCR signaling pathway) (BCR signaling pathway)

The B-cell receptor (BCR) signaling pathway is a fundamental biological process responsible for the activation, proliferation, and differentiation of B-lymphocytes (NCBI: PMC4383113). It begins when an antigen binds to the membrane-bound immunoglobulin on the B-cell surface, triggering a complex cascade of intracellular signaling events involving the CD79A/CD79B heterodimer and kinases such as Spleen Tyrosine Kinase (SYK) and Bruton's Tyrosine Kinase (BTK) (StatPearls: NBK539860). Successful signaling ultimately leads to the maturation of B-cells into plasma cells, which are responsible for the large-scale production of Immunoglobulin G (IgG) and other antibody classes (Janeway's Immunobiology). In healthy individuals, this pathway is essential for the humoral immune response, providing protection against a wide array of pathogens. However, aberrant signaling within this pathway is frequently implicated in the pathogenesis of B-cell malignancies, such as chronic lymphocytic leukemia and various non-Hodgkin lymphomas (Nature Reviews Immunology). It also plays a central role in autoimmune disorders, where the pathway drives the production of self-reactive IgG antibodies that cause tissue damage. Pharmacological targeting of this pathway includes the use of monoclonal antibodies like rituximab to deplete B-cells and small-molecule inhibitors like ibrutinib to block signal transduction (PubMed: 29346730). These therapies are designed to suppress overactive immune responses or eliminate malignant cell populations by disrupting the production of pathogenic IgG.

Other names

B-cell receptors and immunoglobulin G production pathwayB-cell activation pathwayBCR-IgG production pathwayB-cell receptor signaling cascade

Inhibition of B-cell receptor-mediated signal transduction (e.g., via BTK or SYK inhibition), depletion of B-lymphocytes through antibody-dependent cellular cytotoxicity (ADCC), or neutralization of B-cell survival factors (e.g., BAFF) to reduce the population of IgG-secreting cells.