B Cell Receptor and BAFF Receptor Signaling Regulation of B Cell Homeostasis

Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA.
The Journal of Immunology (Impact Factor: 5.36). 10/2009; 183(6):3561-7. DOI: 10.4049/jimmunol.0800933
Source: PubMed

ABSTRACT B lymphocyte homeostasis depends on tonic and induced BCR signaling and receptors sensitive to trophic factors, such as B cell-activating factor receptor (BAFF-R or BR3) during development and maintenance. This review will discuss growing evidence suggesting that the signaling mechanisms that maintain B cell survival and metabolic fitness during selection at transitional stages and survival after maturation rely on cross-talk between BCR and BR3 signaling. Recent findings have also begun to unravel the molecular mechanisms underlying this crosstalk. In this review I also propose a model for regulating the amplitude of BCR signaling by a signal amplification loop downstream of the BCR involving Btk and NF-kappaB that may facilitate BCR-dependent B cell survival as well as its functional coupling to BR3 for the growth and survival of B lymphocytes.

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