title: TCR gamma/delta positive lymphocytes after allogeneic bone marrow transplantation.
abstract: Peripheral gamma/delta+ T cells were studied in patients following allogeneic bone marrow transplantation (BMT) by indirect immunofluorescence utilizing two monoclonal antibodies (G1 and A13) able to recognize the two major subpopulations (V delta 2+ and V delta 1+, respectively) of these cells. We found that the relative percentage of 'total' (gamma/delta+ T lymphocytes) (V delta 2 + V delta 1 positive cells), and particularly of G1+ (V delta 2+) cells, in CD3+ lymphocytes was higher in transplanted patients, and especially in those presenting with acute graft-versus-host disease (aGVHD), than in normal controls. This finding was confirmed by the analysis of the V delta 2+/V delta 1+ cell ratio which was again significantly higher in patients with aGVHD as compared to controls. Similarly, the absolute number of 'total' gamma/delta+ and V delta 2+ cells was also significantly increased in patients with aGVHD. TCR gamma/delta+ T cells increased as a function of time after BMT reaching a plateau value at about day 60 post-BMT. When patients were stratified for the presence or absence of aGVHD this correlation was maintained only for patients with aGVHD. Finally, most V delta 2+ cells expressed surface T cell activation markers such as CD25 (IL-2 receptor) and DR (MHC class II) antigens. Our results suggest a possible involvement of gamma/delta+ T cells and particularly of V delta 2+ cells in the clinical and immunological events (aGVHD) occurring after allogeneic BMT.
authors.affiliation: Istituto Nazionale per la Ricerca sul Cancro (IST), Servizio di Farmacologia, Genova, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Viale
authors.forename: S
authors.initials: S
authors.lastname: Ferrini
authors.forename: A
authors.initials: A
authors.lastname: Bacigalupo
mesh_terms: D000943:Antigens, Differentiation; D016026:Bone Marrow Transplantation / Q000276:immunology*; D006801:Humans; D007938:Leukemia / Q000097:blood / Q000276:immunology / Q000601:surgery; D008213:Lymphocyte Activation; D016692:Receptors, Antigen, T-Cell, gamma-delta; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014184:Transplantation, Homologous
chemical_list: D000943:Antigens, Differentiation; D016692:Receptors, Antigen, T-Cell, gamma-delta