CD8 + recent thymic emigrants home to and efficiently repopulate the small intestine epithelium

• Published in: Nature immunology Vol. 7; no. 5; pp. 482 - 488
• Main Authors: Butcher, Eugene C, Staton, Tracy L, Habtezion, Aida, Winslow, Monte M, Sato, Tohru, Love, Paul E
• Format: Journal Article
• Language: English
• Published: United States Nature Publishing Group 01.05.2006
• Subjects: Animals; CD8 lymphocytes; CD8-Positive T-Lymphocytes - cytology; CD8-Positive T-Lymphocytes - immunology; Cell migration; Cell Movement - immunology; Epithelial Cells - immunology; Genetic aspects; Health aspects; Immune response; Intestine, Small - cytology; Intestine, Small - immunology; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Physiological aspects; Receptors, Lymphocyte Homing - immunology; Severe Combined Immunodeficiency; Thymus Gland - cytology; Thymus Gland - immunology; United States
• ISSN: 1529-2908; 1529-2916
• DOI: 10.1038/ni1319

Prevailing knowledge dictates that naive alphabeta T cells require activation in lymphoid tissues before differentiating into effector or memory T cells capable of trafficking to nonlymphoid tissues. Here we demonstrate that CD8(+) recent thymic emigrants (RTEs) migrated directly into the small intestine. CCR9, CCL25 and alpha(4)beta(7) integrin were required for gut entry of CD8(+) RTEs. After T cell receptor stimulation, intestinal CD8(+) RTEs proliferated and acquired a surface phenotype resembling that of intraepithelial lymphocytes. CD8(+) RTEs efficiently populated the gut of lymphotoxin-alpha-deficient mice, which lack lymphoid organs. These studies challenge the present understanding of naive alphabeta T cell trafficking and suggest that RTEs may be involved in maintaining a diverse immune repertoire at mucosal surfaces.