[Ion channels on T lymphocyte]

There is increasing evidence to show that ion channels on lymphocytes play a very important role in the regulation of immune functions. In T lymphocytes, there are three types of ion channels on cell membrane: Ca2+, K+ and Cl- channel. The influx of Ca2+ into T lymphocyte through Ca2+ channel (CRAC) may act as a second messenger to activate T lymphocyte when antigen binds to the receptor (TCR). The efflux of K+ from T lymphocyte through the K+ channel contributes to the formation of T cell membrane potential. The level of the membrane potential may affect the influx of Ca2+ into T cells. Therefore, the activation and the functions of T cell can be regulated by K+ channel indirectly. Cl- channel in T lymphocyte was found in recent years and it is probably involved in the regulation of cell volume. The recent progress on ion channels in T lymphocyte is summarized briefly in the present paper.