Ligand-independent tonic signaling in B-cell receptor function

Curr Opin Immunol. 2004 Jun;16(3):288-95. doi: 10.1016/j.coi.2004.03.010.


The random and inherently imprecise process of V(D)J recombination is the foundation for generation of the B-cell receptor (BCR). Signals must be generated to trigger selective processes that retain cells expressing a functional BCR, and these signals must be antigen-independent to insure an unbiased and diverse pool of newly formed B cells. Moreover, BCR expression, and presumably signaling, is essential for the continued survival of the B cell. Although BCR signaling is generally thought to depend upon ligand-induced aggregation, recent studies argue that some aspects of BCR signaling occur independently of antigen, and, furthermore, these non-induced or 'tonic' signals are linked to specific cellular processes operating at multiple stages of B-cell development. The potential co-existence of tonic and induced signaling suggests a unique aspect of BCR complexes, or at least an aspect of receptors that has previously been under-appreciated.

Publication types

  • Review

MeSH terms

  • Animals
  • B-Lymphocytes / immunology*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / immunology
  • Humans
  • Lymphocyte Activation / genetics
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Knockout
  • Nuclear Proteins
  • Receptors, Antigen, B-Cell / immunology*
  • Recombination, Genetic / genetics
  • Recombination, Genetic / immunology*
  • Signal Transduction / genetics
  • Signal Transduction / immunology*
  • VDJ Recombinases / genetics
  • VDJ Recombinases / immunology


  • DNA-Binding Proteins
  • Nuclear Proteins
  • RAG2 protein, human
  • Rag2 protein, mouse
  • Receptors, Antigen, B-Cell
  • V(D)J recombination activating protein 2
  • VDJ Recombinases