Nonviral gene gun mediated transfer into the beating heart

Several techniques for gene transfer into the heart have been developed, including direct injection of naked plasmid DNA into the myocardium and coronary infusion of various viral vectors. However, complications and side effects with those methods have been reported. In this study, to resolve these problems, the authors investigated the feasibility of nonviral gene transfer into the beating heart with the hand held gene gun. The genes pCAGGS/CTLA4-EGFP were coated around the surface of gold particles. Three sizes of gold particles (0.6, 1.0, and 1.6 microm in diameter) and three settings of helium gas pressure (200, 250, and 300 psi) were examined. Gene transfer into the rat beating heart was performed using the hand held gene gun. EGFP expressions were detected by fluorescence microscopy from day 1 to 3 weeks after bombardment. The most prominent expressions were detected with the combination of 1.0 microm gold particles and 300 psi helium gas pressure. In this study, the present authors showed that non-viral gene transfer into the beating heart was feasible with the hand held gene gun. This technique is effective for gene transfer into the heart and may be one of the most useful methods for gene therapy for many cardiovascular diseases in the future.