CD4, CD8 and the TCR-CD3 complex: a novel class of protein-tyrosine kinase receptor.

A novel form of receptor-kinase interaction was first described in the interaction between the CD4 and CD8 antigens and the protein-tyrosine kinase p56lck. This linkage, between a regulatory antigen on T cells and a member of a family of intracellular molecules with an established ability to activate and transform cells, is likely to be of great importance in the regulation of T-cell growth. Recently, data have been obtained on the molecular basis of regulation of the CD4/CD8-p56lck interaction and an interaction between the T-cell receptor complex (TCR-CD3) and another src-kinase p59fyn has been described. Here, Christopher Rudd examines these interactions and outlines their potential roles in normal and malignant T-cell growth.