[Impaired signal transduction in T-lymphocytes of the aged].

An age-related dysfunction of the immune system, and especially of the T lymphocytes, is the most common feature observed during aging. It is well recognized by now that changes in the molecular mechanisms connecting the antigen receptor of the T cell with its nuclear machinery, commonly called 'signal transduction pathways' are the basis for this dysfunction. This paper is an up-to-date review of current literature of the problem, describing age-related changes in the functioning of three major, complementary pathways of signal transduction in murine and human T cell: IP3/Ca2+/calcineurin, DAG/protein kinase C (PKC) and Ras/MAP kinases, discovered so far.