Genetic Vaccines and Therapy

Background: Tumor cells such as leukemia and lymphoma cells are possible targets for gene therapy. However, previously leukemia and lymphoma cells have been demonstrated to be resistant to most of non-viral gene transfer methods. Methods: The aim of this study was to analyze various methods for transfection of primary leukemia cells and leukemia cell lines and to improve the efficiency of gene delivery. Here, we evaluated a novel electroporation based technique called nucleofection. This novel technique uses a combination of special electrical parameters and specific solutions to deliver the DNA directly to the cell nucleus under mild conditions. Results: Using this technique for gene transfer up to 75% of primary cells derived from three acute myeloid leukemia (AML) patients and K562 cells were transfected with the green flourescent protein (GFP) reporter gene with low cytotoxicity. In addition, 49(+/9.7%) of HL60 leukemia cells showed expression of GFP. Conclusion: The non-viral transfection method described here may have an impact on the use of primary leukemia cells and leukemia cell lines in cancer gene therapy. Background Leukemia cells are obvious and attractive targets for gene transfer since these cells are potentially susceptible to immunotherapeutic strategies. Recently, cytokine gene transfer and expression of immunomodulatory genes in various kinds of tumor cells have been shown to mediate tumor regression and antimetastatic effects in several animal models [1]. Many leukemic entities respond to a treatment with interferon-alpha [2]. Therefore, gene transfer of various cytokine genes such as interleukin-2 (IL-2), IL-7 and IL-12 has been envisaged [3,4]. Despite of expressing MHC molecules, leukemia cells are ineffective antigen presenting cells (APC) [5]. Often leukemic cells are unable to stimulate T cells because they lack expression of important co-stimulatory molecules [5]. The use of vectors expressing co-stimulatory molecules or cytokines and the Published: 12 January 2004 Genetic Vaccines and Therapy 2004, 2:1 Received: 26 September 2003 Accepted: 12 January 2004 This article is available from: http://www.gvt-journal.com/content/2/1/1 © 2004 Schakowski et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.