EFFICIENT TRANSFER OF OLIGONUCLEOTIDES AND PLASMID DNA INTO THE WHOLEHEART THROUGH THE CORONARY-ARTERY

Several of the current techniques for transfer of both oligonucleotide and plasmid DNA into the myocardium are impaired by low efficiency an d toxicity. To improve gene transfer techniques, especially into the w hole heart, a gene transfer method involving liposome in conjunction w ith a viral envelope (HVJ-liposome) was essayed as an alternative. FIT C-labeled oligonucleotide (F-ODN) and the cDNA of beta-galactosidase ( beta-gal) were introduced into the myocardium by coronary infusion of HVJ-liposome during cardioplegic arrest of adult Sprague-Dawley rat he arts. Then, transfected heart was ectopically transplanted into anothe r rat abdomen of the same strain to maintain the transfected heart lon g enough to allow for protein synthesis. After 3 days of transfection, transfected heart was excised and the efficiency of gene transfection was evaluated. FITC was detected in the nuclei of more than 70% of th e myocytes and endothelial cells both in the epicardium and endocardiu m. beta-Gal was expressed in the cytosol of more than 50% of the myocy tes. beta-Gal expression was demonstrated : by Western blotting analys is at day 3 after transfection and continued for at least 14 days. No significant histological damage of the myocardium or leakage of CPK we re detected in the rats transfected by the HVJ-liposome method. These results clearly demonstrate that the hearts were efficiently transfect ed both by oligonucleotide and plasmid DNA as a result of coronary inf usion of HVJ-liposome during cardioplegic arrest. This thus appears to be an efficient method for gene transfer into the whole heart, provid ing a new tool Pox: research and therapy for heart diseases.