Polyclonal T-cell activation protocol stimulates preferential expansion of EBV-specific T-cell clones in vitro.
OBJECTIVE
Allogeneic bone marrow transplantation (AlloBMT) can be curative for patients with leukemia. The most important anti-leukemic effect may be mediated by the T-cells contained within the graft; however, the allogeneic T-cells may also give rise to graft-vs-host disease (GVHD). One way to control GVHD might be to transduce the donor T-cells with a drug-inducible suicide gene. If a retrovirus vector is to be used for this transduction, activation of the T-cells is required for integration of the transgene to occur. The activation protocol should ensure expansion of a broad repertoire of donor T-cells. Notably, T-cells specific for herpes virus family antigens are important for adoptive immunoprotection.


METHODS
To define optimal activation conditions for retrovirus-mediated suicide gene transduction of donor T-cells, we examined the repertoire of CD8+ T-cells in general, and Epstein-Barr virus (EBV) specific T-cells in particular, following two different activation and expansion procedures.


RESULTS
We found that repeated CD3/CD28 stimulation resulted in a high level of activation-induced T-cell death, affecting in vivo expanded clones, some of which were specific for EBV, in particular. In contrast, initial CD3/CD28 activation followed by proliferation in interleukin-2 lead to expansion of EBV-specific clones over and above the expansion observed for CD8+ T-cells in general.


CONCLUSIONS
These results should impact on protocols for ex vivo activation of T-cells prior to suicide gene transduction.
Hedfors
Ida Aagård
IA
Institute of Immunology, Rikshospitalet University Hospital, 0027 Oslo, Norway.
Brinchmann
Jan E
JE
D017209:Apoptosis / Q000502:physiology; D018106:CD28 Antigens / Q000378:metabolism; D017252:CD3 Complex / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology* / Q000821:virology; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D018014:Gene Transfer Techniques; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D016130:Immunophenotyping; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*
D018106:CD28 Antigens; D017252:CD3 Complex; D007376:Interleukin-2