Background: Survivin is a rather specific gene in tumor tissue. We transfected dendritic cells (DCs) with recombinant adenovirus (Ad) containing survivin gene and granulocyte-macrophage colony-stimulating factor (GM-CSF) gene and tested the inducing effect of the transfected DCs on cytotoxic T lymphocytes (CTL) to kill leukemic cells.
Methods: After derived from the peripheral, DCs was assayed by mixed leukocyte reaction (MLR) tests. Lactate dehydrogenase (LDH) release test was used to evaluate cytotoxicity of CTL.
Results: Expression of survivin in transfected DCs was confirmed by Western blotting analysis. GM-CSF expression was confirmed by enzyme-linked immunosorbent assay (ELISA). In MLR assay, DCs coinfected with Ad-survivin and Ad-GM-CSF induced higher allogeneic lymphocyte reaction than control DCs at ratios of 1:5, 1:10, 1:50 and 1:100. DCs coinfected with Ad-survivin and Ad-GM-CSF had much higher activity of CTL to HL-60 cells than DCs infected with Ad-survivin only, Ad-GM-CSF only, or control DCs. Levels of interleukin-12 (IL-12) and interferon gamma (IFN-gamma) in lymphocyte supernatants containing DCs coinfected with Ad-survivin and Ad-GM-CSF were significantly higher than those in the control group.
Conclusion: DCs coinfected with Ad-survivin and Ad-GM-CSF induce much higher anti-leukemic response in vitro than those infected with either factor. Therefore, adenovirus vectors containing survivin and GM-CSF genes may be promising vaccine candidates for leukemia therapy.