B‐lymphocyte Activation


B‐lymphocyte activation is initiated by the binding of antigen to the B‐cell receptor (BCR), which leads to an intricate web of downstream intracellular signalling events that ultimately results in a specific immune response. Breakdown in any of the multiple signalling cascades controlling B‐lymphocyte activation can result not only in impaired B‐cell development and immunodeficiency, but also in a predisposition to autoimmunity and malignancy.

Keywords: B‐cell activation; signalosome; B‐cell signalling; BCR

Figure 1.

The signalling events during B‐cell activation. A plethora of signalling molecules become activated upon BCR cross‐linking, modulated by the activation of stimulatory and inhibitory coreceptors.

Figure 2.

Non‐BCR‐mediated B‐cell activation pathways. The major non‐BCR‐mediated pathways, which contribute to B‐cell activation by a variety of stimuli: (a) complement factors; (b) contact‐mediated T‐cell help; (c) LPS, CpG motifs in bacteria; (d) BAFF‐mediated survival signals; (e) Notch activation by cells expressing Delta‐like or Jagged family of ligands.



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Further Reading

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Khan, Mamnunur, and Turner, Martin(Apr 2006) B‐lymphocyte Activation. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0004209]