Molecular properties and physiological roles of ion channels in the immunesystem

The discovery of a diverse and unique set of ion channels in T lymphocytes has led to a rapidly growing body of knowledge about their functional roles in the immune system. Here we review the biophysical and molecular charact erization of K+, Ca2+, and Cl- channels in T lymphocytes. Potent and specif ic blockers, especially of K+ channels, have provided molecular tools to el ucidate the involvement of voltage- and calcium-activated potassium channel s in T-cell activation and cell-volume regulation. Their unique and differe ntial expression makes lymphocyte K+ channels excellent pharmaceutical targ ets for modulating immune system function. This review surveys recent progr ess at the biophysical, molecular, and functional roles of the ion channels found in T lymphocytes.