The thymus chapter in the life of gut-specific intra epithelial lymphocytes.
The intestinal intraepithelial lymphocytes (IEL) represent multi-lineage T cell populations. In addition to a major gammadeltaTCR(+) T cell subset, many IEL express alphabetaTCRs and they can be separated into alphabeta sublineages. Some TCRalphabeta(+)IEL have characteristics in common with conventional TCRalphabeta(+)T cells whereas others share an unconventional phenotype with their TCRgammadelta(+) counterparts. Because the latter are enriched for autoreactive TCRs and can be generated in the absence of a thymus, it has long been postulated that some IEL subsets develop locally in the intestine. Several new data however, indicate that under physiological conditions, IEL require a thymic education that directs lineage commitment and functional differentiation. This review will discuss the contributions of the thymus in shaping the various intestinal IEL sublineages.
Cheroutre
Hilde
H
Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, 9240 Athena Circle, La Jolla, CA 92037, USA. hilde@liai.org
Lambolez
Florence
F
D019070:Cell Lineage; D004847:Epithelial Cells / Q000276:immunology*; D007413:Intestinal Mucosa / Q000276:immunology*; D054504:Precursor Cells, T-Lymphoid / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta