Pre-B and pre-T-cell receptors: conservation of strategies in regulating early lymphocyte development.

Early lymphocyte development is characterized by the regulated activity of the V(D)J recombinase and the positive and negative selection of cells based on the structure of their assembled antigen receptor genes. Developing B and T cells use remarkably similar signaling complexes, the pre-B-cell receptor (pre-BCR) and the pre-T-cell receptor (pre-TCR) respectively, to monitor the progress of antigen receptor gene assembly This review will compare and contrast the regulation and activities of the pre-BCR and pre-TCR signaling complexes. In addition, we will consider a number of critical but as yet unanswered questions prompted by such an analysis.