Dendritic cells (DC) are potent antigen-presenting cells capable of stimulating T cell mediated immunity. Gene transfer of tumor specific antigens or cytokines into DC would be a useful strategy for immunotherapeutical purposes. In the present study, in vitro transfection of human DCs (hDC) with the complex of biodegradable cationized gelatin and an EGFP gene was performed. Flow cytometric analyses revealed that approximately 14% of DC was positively expressed for EGFP, and the mRNA expression of EGFP gene in transfected hDC was detected by RT-PCR. Additionally, when evaluated by allogeneic MLR, the antigen-presenting capacity of transfected DC was equal to that of control DC. Cationized gelatin is a promising nonviral vector for gene transfer into DC.