Insights into T Cell Development and Signal Transduction Provided by TCR-ζ Chain Deficient Mice

Abstract

The T cell antigen receptor (TCR) transduces signals that mediate different responses depending on the stage of development of the T cell and the nature of the ligand it engages. The presence of multiple signal transducing subunits (CD3-γ-δ,-ε and ζ chain) suggests the potential to control these responses by altering the subunit composition of the TCR. ζ chain represents an especially important signalling molecule as it contains multiple signalling motifs within its cytoplasmic tail. The generation and analysis of ζ deficient (ζ^−/−) and ζ-transgenic mice has provided insight into the role of ζ as well as the CD3 subunits in TCR surface expression, T cell activation and thymocyte development. Herein, we discuss the results from such experiments which suggest distinct roles for ζ chain and the CD3 components at different stages of T cell development.