B-cell receptor (BCR) (BCR)

The B-cell receptor (BCR) is a critical transmembrane protein complex found on the surface of B lymphocytes, consisting of an antigen-binding membrane immunoglobulin (mIg) and a signaling subunit composed of CD79A and CD79B heterodimers (StatPearls, 2023). Its primary role is to recognize and bind specific antigens, initiating intracellular signaling pathways such as the PI3K/Akt and MAPK pathways that drive B-cell maturation, survival, and antibody production (UniProt, 2024). In many B-cell malignancies, including chronic lymphocytic leukemia (CLL) and mantle cell lymphoma, the BCR pathway is often constitutively active, providing essential survival signals to malignant cells (PubMed, PMC6548359). Therapeutic strategies often focus on inhibiting downstream kinases like Bruton's tyrosine kinase (BTK) or Spleen tyrosine kinase (Syk) to disrupt this signaling, or directly targeting subunits like CD79B with antibody-drug conjugates (NIH, 2023). Drugs such as ibrutinib and polatuzumab vedotin have revolutionized the treatment of these cancers by targeting the BCR signaling axis (PubChem, 2024). These agents effectively block the survival signals transmitted through the BCR, inducing apoptosis in malignant B cells. Additionally, the BCR plays a central role in the pathogenesis of autoimmune diseases, where it may recognize self-antigens and trigger harmful immune responses (Wikipedia, 2024). Therapeutic modulation of the BCR is therefore a cornerstone of modern hematology and immunology.

Other names

BCR complexSurface immunoglobulinsIgAntigen receptor of B cellsmIg-CD79 complex

Inhibition of the B-cell receptor signaling pathway through direct targeting of receptor subunits or downstream signaling kinases such as BTK, Syk, and PI3K to arrest B-cell proliferation and induce apoptosis.