Cyclin-dependent kinases: molecular switches controlling anergy and potential therapeutic targets for tolerance.

A large body of research has established the importance of costimulatory signals and proliferation for the generation of productive T cell immune responses. While costimulation and cell cycle progression are each individually necessary for CD4+ effector T cell differentiation, it has become clear that neither of these processes alone is sufficient to avoid anergy. This review outlines the links between T cell differentiation, tolerance, and the cell cycle, and highlights recent work that has implicated cyclin-dependent kinases as important regulators and potential targets for modulation of T cell immunity and tolerance.