title: Human peripheral blood gamma delta T cells are uniformly sensitive to destruction by the lysosomotropic agents leucine methyl ester and leucyl leucine methyl ester.
abstract: Treatment of peripheral blood mononuclear cells (PBMC) with the lysosomotropic agent leucine methyl ester (Leu-OMe) eliminates monocytes/macrophages and cytotoxic lymphocytes including CD3- CD16+ natural killer (NK) cells and a fraction of T cell receptor (TcR) alpha beta + CD8+ T cells. We report that freshly isolated peripheral blood gamma delta T cells are highly sensitive to Leu-OMe treatment as well. After incubation of PBMC with 5 mM Leu-OMe or incubation of purified T cells with 50 microM leucyl leucine methyl ester (Leu-Leu-OMe) and subsequent overnight culture, CD3-CD16+ NK cells and gamma delta T cells were no longer detectable by immunofluorescence analysis. The two major gamma delta T cell subsets V gamma 9+V delta 2+ and V gamma 9-V delta 1+ were equally susceptible to Leu-OMe and Leu-Leu-OMe treatment. The elimination of V gamma 9+ T cells by Leu-OMe treatment was confirmed in functional assays. Stimulation of peripheral blood T cells with killed mycobacteria resulted in selective expansion of V gamma 9+ T cells. In contrast, no activation of gamma delta T cells was elicited in Leu-OMe-treated responder T cells stimulated with killed mycobacteria.
authors.affiliation: Institut für Immunologie, Universität Heidelberg, FRG.
authors.forename: K
authors.initials: K
authors.lastname: Pechhold
authors.forename: D
authors.initials: D
authors.lastname: Kabelitz
mesh_terms: D001769:Blood; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D004151:Dipeptides / Q000276:immunology*; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D007166:Immunosuppressive Agents / Q000276:immunology*; D007930:Leucine / Q000031:analogs & derivatives* / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D004151:Dipeptides; D007166:Immunosuppressive Agents; D016692:Receptors, Antigen, T-Cell, gamma-delta; C045139:leucyl-leucine-methyl ester; C030365:leucine methyl ester; D007930:Leucine