Adeno-associated viral vector transduction of green fluorescent protein in kidney: effect of unilateral ureteric obstruction.

OBJECTIVE: To evaluate adeno-associated virus (AAV) mediated renal gene transfer, by examining the localization and time course of gene expression in the kidneys of mice with unilateral ureteric obstruction (UUO) and controls. AAV is a replication-defective virus that has the potential to deliver genes into the kidney to improve renal damage after UUO.
MATERIALS AND METHODS: An AAV vector carrying a green fluorescent protein (GFP) reporter gene (rAAV-GFP) was used. In control mice, GFP expression was evaluated at 4, 7, 14 and 28 days after intrapelvic injection of rAAV or phosphate-buffered saline (PBS). In mice with UUO, the left ureter was obstructed, and 24 h later either rAAV or PBS was injected; GFP expression was evaluated 4, 7 and 14 days later by direct fluorescence.
RESULTS: In the control mice, at least 7 days was required to detect GFP expression, whereas after UUO, GFP expression was already evident at 4 days after injection. GFP was localized mainly to the medullary tubules.
CONCLUSIONS: This study shows successful transduction of GFP into mouse kidney using an AAV vector; GFP was expressed sooner in UUO kidneys than in the controls. These results show the feasibility of using AAV to transduce GFP into the obstructed kidney, and suggest that it might be useful in transducing therapeutically active agents.