CD79

Utilization

CD79 serves to be a pan-B cell marker for the detection of B-cell neoplasms. However, tumor cells in some cases of T-lymphoblastic leukemia/lymphoma and AML has shown to potentially react positively with CD79 monoclonal antibodies. In addition, both CD79 chains contain an immunoreceptor tyrosine-based activation motif (ITAM), which some scientists have found to propagate downstream signaling in B-cells. CD79 has been tested as a B-cell target in MRL/lpr mice, a mouse model for systemic lupus erythematosus (SLE). CD79, expressed by B-cell and plasma cell precursors is a candidate that induces apoptosis as well as inhibition of B-cell receptor (BCR) activation and possibly depletion of ectopic germinal centers (GC). However, research on CD79 still remains very open.

CD79 and BCR Signaling

Scientists identified mutations in the BCR coreceptor CD79A/B that lead to chronic activation of BCR signaling. Somatic mutations affecting the ITAM signaling modules of CD79B and CD79A were detected frequently in biopsy samples. Moreover, some researchers believe that CD79 may emerge as an alternative target for the treatment of B-cell-dependent autoimmunity. Hardy et al. found that upon an Ag-induced BCR aggregation, CD79 is phosphorylated and initiates a cascade of downstream signaling events. Hardy et al. further characterized an alternate mode of BCR signaling that is induced by chronic AgR stimulation and maintains a state of B cell unresponsiveness termed "anergy". Other studies that focused on the deficiencies observed in neonatal antibody production can be due to various intrinsic features such as B-cell immaturity, poor B-cell repertoire or reduced strength of BCR signaling. Activation of the BCR with T-cell-dependent (TD) or TI antigens induces cross-linking of surface Ig molecules and binding to the transmembrane protein CD79.

References

References

1. (June 2001). "CD79: a review". Applied Immunohistochemistry & Molecular Morphology.
2. (June 1992). "Comparison of human B cell antigen receptor complexes: membrane-expressed forms of immunoglobulin (Ig)M, IgD, and IgG are associated with structurally related heterodimers". The Journal of Experimental Medicine.
3. (January 1995). "Interplay between the human TCR/CD3 epsilon and the B-cell antigen receptor associated Ig-beta (B29)". Immunology Letters.
4. (2013). "Atlas of Hematopathology".
5. (November 2011). "B-cells and their targeting in rheumatoid arthritis--current concepts and future perspectives". Autoimmunity Reviews.
6. (January 2010). "Chronic active B-cell-receptor signalling in diffuse large B-cell lymphoma". Nature.
7. (September 2008). "B cell depletion with anti-CD79 mAbs ameliorates autoimmune disease in MRL/lpr mice". Journal of Immunology.
8. (February 2014). "Anti-CD79 antibody induces B cell anergy that protects against autoimmunity". Journal of Immunology.