CD8+ recent thymic emigrants home to and efficiently repopulate the small intestine epithelium.
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.
Program in Immunology, Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA.
Tracy L
TL
Staton
Aida
A
Habtezion
Monte M
MM
Winslow
Tohru
T
Sato
Paul E
PE
Love
Eugene C
EC
Butcher
D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002465:Cell Movement / Q000276:immunology; D004847:Epithelial Cells / Q000276:immunology*; D007421:Intestine, Small / Q000166:cytology / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016201:Receptors, Lymphocyte Homing / Q000276:immunology*; D016511:Severe Combined Immunodeficiency; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology
D016201:Receptors, Lymphocyte Homing