Influence of T cell depletion method on circulating gammadelta T cell reconstitution and potential role in the graft-versus-leukemia effect

Cytotherapy. 1999;1(1):7-19. doi: 10.1080/0032472031000141295.


Background: Our laboratory previously reported that leukemia patients who developed > or = 10% gammadelta+ T cells during the first six months after receiving an anti-TCRalphabeta T-cell-depleted (TCD) graft from a partially mismatched related donor (PMRD) had a disease-free survival (DFS) advantage. These gammadelta+ T cells were V81+CD3+CD4-CD8-CD69+HLADR+ and are cytotoxic to K562 cells.

Methods: In order to determine whether the anti-alphabeta TCD regimen was associated with these findings, we compared the reconstitution of gammadelta+ T cells from patients who received TCD PMRD grafts using the anti-TCRc4 MAb TIOB9-1A31 (previously reported) with similar patients who received grafts using the anti-CD3 MAb OKT3.

Results: Increased cytotoxic Vdelta1+ T cells were seen in 10 of 43 T10B9 TCD patients compared to 7 of 100 in the OKT3 TCD group (23% versus 7%, p = 0.010). T10B9 patients with increased gammadelta+ T cells also exhibited a higher range of increased gammadelta+ T cells and the length of time the gammadelta+ T cells remained high was longer when compared to OKT3 patients. Patients with increased gammadelta+ T cells whose grafts were T-cell depleted with T10B9 showed a significant decrease in relapse (p = 0.038). Similar rates and reduction in relapse were seen in OKT3 TCD patients, although significance was not reached due to the small number of patients with increased gammadelta+ T cells. Estimated 3 year disease-free survival was significantly improved in T10B9 patients with increased gammadelta+ T cells (0.79 versus 0.31, p = 0.009), a trend also seen in OKT3 patients (p = 0.091).

Discussion: These observations indicate that Vdelta1+CD4-CD8-cytotoxic T cells are associated with lower relapse rates and improved survival, and thus may have a role in a graft-versus-leukemia effect.

Publication types

  • Clinical Trial

MeSH terms

  • Adolescent
  • Adult
  • Blood Transfusion / methods
  • Cell Proliferation*
  • Child
  • Child, Preschool
  • Female
  • Graft vs Leukemia Effect / immunology*
  • Humans
  • Infant
  • K562 Cells
  • Leukemia / immunology
  • Leukemia / mortality
  • Leukemia / therapy
  • Lymphocyte Depletion / methods*
  • Male
  • Middle Aged
  • Receptors, Antigen, T-Cell, gamma-delta / metabolism*
  • Survival Analysis
  • T-Lymphocytes / cytology*
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / physiology*
  • Young Adult


  • Receptors, Antigen, T-Cell, gamma-delta