TRANSMEMBRANE SIGNALING BY ANTIGEN RECEPTORS OF B-LYMPHOCYTES AND T-LYMPHOCYTES

The specificity of immune responses depends upon the activation of onl y those lymphocytes that recognize the introduced antigen. In recent y ears, a great deal has been learned about the structure of lymphocyte receptors for antigens and about their signal transduction mechanism. These receptors activate intracellular protein tyrosine kinases of at least two families, the Src family and the Syk/ZAP-70 family. Recent s tudies have given us considerable insight into the interactions of the se two types of kinases and how they mediate antigen receptor signalin g.