title: gammadelta T-cell clones from intestinal intraepithelial lymphocytes inhibit development of CTL responses ex vivo.
abstract: Oral administration of antigen induces a state of tolerance that is associated with activation of CD8+ T cells that can transfer unresponsiveness to naïve syngeneic hosts. These T cells are not lytic, but they inhibit development of antibody, CD4+ T helper cell, and CD8+ cytotoxic T lymphocyte (CTL) responses upon adoptive transfer into naïve, syngeneic mice. In addition, we have shown that depletion of gammadelta T cells by injection of the anti-delta chain antibody (GL3) down modulates the expression of gammadelta T-cell receptor (TCR) and inhibits the induction of oral tolerance to ovalbumin. Oral administration of antigen also fails to induce tolerance in TCR delta-chain knockout mice suggesting that gammadelta T cells play a critical, active role in tolerance induced by orally administered antigen. To further study the contribution of gammadelta T cells to tolerance, murine gammadelta T cells were isolated from intraepithelial lymphocytes (IEL) of the small intestine by stimulation with splenic filler cells, concanavalin A and growth factors. gammadelta IEL lines demonstrated lytic activity in a redirected lysis assay. gammadelta T-cell clones express different gammadelta TCR genes and secrete large amounts of interleukin (IL)-10, but little or no IL-2, IL-4, or interferon-gamma. gammadelta IEL clones expressed transforming growth factor-beta1 and macrophage migration inhibitory factor, as well as IL-10, mRNA. Moreover, gammadelta T-cell clones potently inhibited the generation of CTL responses by secreted molecules rather than by direct cell-to-cell contact.
authors.affiliation: Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA 30322, USA. jkapp@emory.edu
authors.forename: Judith A
authors.initials: JA
authors.lastname: Kapp
authors.forename: Linda M
authors.initials: LM
authors.lastname: Kapp
authors.forename: Kyle C
authors.initials: KC
authors.lastname: McKenna
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Lake
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D002999:Clone Cells / Q000276:immunology; D003602:Cytotoxicity, Immunologic / Q000276:immunology; D004847:Epithelial Cells / Q000276:immunology; D007108:Immune Tolerance; D018928:Immunity, Mucosal; D016130:Immunophenotyping; D007413:Intestinal Mucosa / Q000276:immunology*; D007421:Intestine, Small / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta