TCR gamma/delta positive lymphocytes after allogeneic bone marrow transplantation
Viale, M.; Ferrini, S.; Bacigalupo, A.
Bone Marrow Transplantation 10(3): 249-253
1992
ISSN/ISBN: 0268-3369 PMID: 1422478 Document Number: 404192
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.