Dual TCR-expressing T lymphocytes in health and disease

The authors briefly review recent experimental advances in elucidating the role of dual T cell receptor (TCR)expressing lymphocytes in the developemen t of diseases with special emphasis on autoimmunity. Moreover, they summari ze present knowledge about these cells concerning their proportion among pe ripheral blood mononuclear cells, their functionality, and their impact on allorecognition and memory both in humans and in mice. Finally, they descri be disease-associated clonal expansions of dual TCR-expressing cells in hum ans, most of which have been observed in peripheral T cell malignancies. Ot her cases occurred in inflammatory bowel disease and in HIV infection. They propose that expression of two distinct TCR on malignant T lymphocytes mig ht be much higher than is suggested by the few cases described so far, and that their presence might impinge on therapeutic immunization strategies wh ich make use of the TCR itself as a target. Copyright (C) 2001 S.Karger AG, Basel