title: Regional specialization of intraepithelial T cells in the murine small and large intestine.
abstract: We investigated intraepithelial T cells from the small intestine, SI (jejunum, ileum) and the large intestine, LI (colon) of euthymic (BALB/c, H-2d; C.B-17+/+, H-2d; C57BL/6, H-2b) and athymic (C57BL/6 nu/nu; BNX bg/bg nu/nu xid/xid) mice. From individual euthymic and athymic mice, 7 x 10(6) intraepithelial lymphocytes (IEL) per mouse were isolated from the SI. Ten-fold lower numbers of IEL were obtained from the LI epithelium (4 x 10(5) IEL per mouse). Thymus-dependent and -independent T cells represented > 80% of SI-IEL but the fraction of T cells was reduced from 20% to 40% in LI-IEL. In euthymic mice, alpha beta T cells predominated in SI-IEL and in particular in LI-IEL populations, while SI-IEL and LI-IEL populations of athymic mice contained predominantly gamma delta T cells. The intraepithelial T cell subset distribution was different in SI versus LI: mainly CD8+ T cells were present in the SI, but a large CD4+ T cell subset was present in the LI. 'Double positive' CD4+ CD8 alpha+ T cells were present mainly in the SI epithelium but were rare in the LI epithelium. In euthymic as well as athymic mice, T cells expressing the homodimeric CD8 alpha alpha isoform predominated in the SI epithelium, while T cells expressing the heterodimeric CD8 alpha beta isoform predominated in the LI epithelium. LI-derived TCR alpha beta+ IEL displayed the CD2+ CD28+ LPAM-1/2- M290+ phenotype, and a fraction of them expressed the L-selectin LECAM-1. In contrast, a large fraction of TCR alpha beta+ SI-IEL was CD2- CD28- LPAM-1/2- M290+ and LECAM-1-. RAG-1/2 expression was detectable by RT-PCR in IEL from the SI but not the LI. Striking differences in phenotype were thus apparent between thymus-dependent and thymus-independent T cells in the epithelial layer of the jejunum/ileum and the colon of the mouse.
authors.affiliation: Department of Bacteriology, University of Ulm, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Boll
authors.forename: A
authors.initials: A
authors.lastname: Rudolphi
authors.forename: S
authors.initials: S
authors.lastname: Spiess
authors.forename: J
authors.initials: J
authors.lastname: Reimann
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis; D001483:Base Sequence; D015815:Cell Adhesion Molecules / Q000096:biosynthesis; D002465:Cell Movement / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D016130:Immunophenotyping; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology*; D007420:Intestine, Large / Q000276:immunology; D007421:Intestine, Small / Q000276:immunology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008819:Mice, Nude; D016513:Mice, SCID; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000276:immunology; D016133:Polymerase Chain Reaction; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta