Protein kinase B (Akt) regulation and function in T lymphocytes

Protein kinase B (PKB)(1-5) is a serine/threonine kinase that is activated by cytokines, antigen receptors, the costimulator CD28 and chemokines in lymphocytes.(6-11) PKB is thus poised to contribute to a variety of immune activation responses. A number of functions have been ascribed to PKB in different cell lineages including the regulation of cell survival, cytokine gene induction and cell cycle progression. In the present article the mechanisms that control PKB activity in T lymphocytes will be reviewed and the function of this kinase in the immune system will be discussed.