Ganciclovir treatment of herpes simplex thymidine kinase-transduced primary T lymphocytes: an approach for specific in vivo donor T-cell depletion after bone marrow transplantation?

Blood. 1994 Aug 15;84(4):1333-41.


Allogeneic bone marrow transplantation (BMT) is associated with a severe complication--graft-versus-host disease (GVHD). Although effectively preventing GVHD, ex vivo T-lymphocyte marrow depletion unfortunately increases graft rejection and reduces the graft-versus-leukemia (GVL) effect. The ex vivo transfer of the herpes simplex thymidine kinase (HS-tk) suicide gene into T cells before their infusion with hematopoietic stem cells could allow for selective in vivo depletion of these T cells with ganciclovir (GCV) if subsequent GVHD was to occur. Thus, one could preserve the beneficial effects of the T cells on engraftment and tumor control in patients not experiencing severe GVHD. To obtain T cells specifically depleted by GCV, we transduced primary T cells with a retroviral vector containing the HS-tk and neomycin resistance (NeoR) genes. Gene transfer was performed by coculturing PHA +/- CD3- or alloantigen-stimulated purified T cells on an irradiated retroviral vector producer cell line or by incubating the T cells in supernatant from the producer. Subsequent culture in G418 for 1 week allowed for the selection of transduced cells. GCV treatment of interleukin-2-responding transduced and selected cells resulted in greater than 80% growth inhibition, whereas GCV treatment of control cells had no effect. Similarly, the allogeneic reactivity of HS-tk-transduced cells was specifically inhibited by GCV. Combining transduced and nontransduced T cells did not show a bystander effect, thus implying that all of the cells inhibited by GCV were indeed transduced. Lastly, studies involving the transduction of the HUT-78 (T-lymphoma) cell line suggest that stable expression of HS-tk can be maintained over 3 months in vitro in the absence of G418. In summary, we have established the feasibility of generating HS-tk-transduced T cells for subsequent in vivo transfer with hematopoietic stem cells and, if GVHD occurs, specific in vivo GCV-induced T-cell depletion in allogeneic BMT recipients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bone Marrow / immunology*
  • Cell Division / drug effects
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Ganciclovir / pharmacology*
  • Gentamicins / pharmacology
  • Humans
  • Interleukin-2 / pharmacology
  • Kinetics
  • Lymphocyte Activation / drug effects
  • Lymphocyte Depletion / methods*
  • Simplexvirus / enzymology*
  • T-Lymphocytes / cytology*
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology*
  • Thymidine Kinase / biosynthesis*
  • Time Factors
  • Transduction, Genetic
  • Transfection


  • Gentamicins
  • Interleukin-2
  • antibiotic G 418
  • Thymidine Kinase
  • Ganciclovir