B cell antigen receptor signaling 101.

All cells continually survey their environment and make decisions based on cues encountered. This requires specific receptors that detect such cues, then transduce signals that initiate the appropriate responses. B lymphocytes provide an archetypal model for such 'adaptive' cellular responses, where signals transmitted by the B cell Ag-receptor (BCR) influence not only cellular selection, maturation, and survival, but are imperative in generating the ultimate effector function of B cells, i.e. antibody production. While other extracellular stimuli and their cognate receptor signals can also influence B cell development, BCR-mediated signals and the way in which they are integrated and regulated are paramount in defining the cell's physiological fate.