title: Intestinal T cells of Dicentrarchus labrax (L.): gene expression and functional studies.
abstract: Cellular and molecular data have evidenced a gut-associated lymphoid tissue in a variety of teleost species, abundantly containing T cells, whose origin, selection and functions are still unclear. This study reports CD4, CD8-α, MHCI-α, MHCII-β, rag-1 and TCR-β gene transcription along the intestine (anterior, middle and posterior segments) and in the thymus of one year-old Dicentrarchus labrax (L.). Real-time PCR findings depicted a main role of the thymus in T-cell development, but also rag-1 and CD8-α transcripts are detected in the intestine, having significant expression in the posterior segment. In the whole intestine TCR-β and CD8-α exceeded CD4 transcripts. RNA ISH confirmed these data and detailed that mucosal CD8-α+ cells were especially numerous in the epithelium and in aggregates in the lamina propria. Regional differences in T-cell-specific gene expressions are first described in the intestine of a bony fish. High non-specific cytotoxic activity against xenogeneic and allogeneic cells was found in lymphocytes purified from the intestinal mucosa, providing further insight into their local defence roles.
authors.affiliation: Department of Environmental Sciences, Tuscia University, Viterbo, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Picchietti
authors.forename: L
authors.initials: L
authors.lastname: Guerra
authors.forename: F
authors.initials: F
authors.lastname: Bertoni
authors.forename: E
authors.initials: E
authors.lastname: Randelli
authors.forename: M C
authors.initials: MC
authors.lastname: Belardinelli
authors.forename: F
authors.initials: F
authors.lastname: Buonocore
authors.forename: A M
authors.initials: AM
authors.lastname: Fausto
authors.forename: J H
authors.initials: JH
authors.lastname: Rombout
authors.forename: G
authors.initials: G
authors.lastname: Scapigliati
authors.forename: L
authors.initials: L
authors.lastname: Abelli
mesh_terms: D000818:Animals; D001492:Bass / Q000276:immunology*; D015704:CD4 Antigens / Q000235:genetics; D003601:Cytotoxicity Tests, Immunologic; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000276:immunology*; D005802:Genes, MHC Class II / Q000235:genetics; D019674:Genes, T-Cell Receptor beta / Q000235:genetics; D007422:Intestines / Q000276:immunology*; D016133:Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
chemical_list: D015704:CD4 Antigens