Direct in vivo gene transfer to urological organs

Patients with urological disorders may benefit from gene based therapy. We investigated the feasibility of delivering exogenous genes into urological tissues in vivo using direct in vivo electrotransfection.

Gene transfer to rat kidneys, testes and bladders was accomplished via direct local injection of pGL3/luciferase and beta-galactosidase reporter gene constructs, followed by an electrical pulse ranging from 55 to 115 msec at 100 V. Direct injection of deoxyribonucleic acid without an electrical pulse served as the control. The transfected and nontransfected organs were retrieved and analyzed by luciferase activity assay, histochemical and immunocytochemical staining for beta-galactosidase, and reverse transcription polymerase chain reaction with primers specific for beta-galactosidase messenger ribonucleic acid.

There was significant luciferase activity 1, 3 and 5 days after direct in vivo electrotransfection in kidneys and testes, and after 3, 5, 7 and 10 days in bladders. Positive beta-galactosidase enzyme activity and beta-galactosidase immunoreactivity were observed in the transfected renal tubular cells, testicular interstitial and germ cells, and uroepithelial bladder layer. Reverse transcription-polymerase chain reaction products of the transfected organs were noted, indicating the successful transcription of messenger ribonucleic acid.

This study demonstrates that direct in vivo electrotransfection is a feasible method of transient gene delivery into intact urological organs. Its apparent safety and relative simplicity suggest that direct in vivo electrotransfection may be useful clinically.