BACKGROUND: Interstitial fibroblasts are central to the inflammatory response during the progression of tubulointerstitial fibrosis. We examined the efficiency of a new gene transfer method that targets interstitial cells by using parenchymal injection of DNA followed by electroporation. METHODS: Fluoresceinisothiocyanate-labelled oligodeoxynucleotides (FITC-ODNs) or expression vectors were directly injected into the cortex of the kidney, followed by electroporation. RESULTS: Transfection with FITC-ODNs or the EGFP expression vector resulted in efficient transfection in interstitial fibroblasts, but not in tubular epithelial cells or glomerular cells. Transfection efficiency was optimal after using a total of 150 microg of DNA in 1000 microl of PBS, combined with clamping of the renal vessels prior to electroporation. Gene expression peaked at 4 days after transfection and decreased by two orders of magnitude at 6 weeks post-transfection; however, expression recovered to near peak levels after parenchymal or intraperitoneal injection of FR901228, a histone deacetylase inhibitor. CONCLUSION: We demonstrated that direct parenchymal injection of DNA combined with electroporation enables gene transfer into interstitial fibroblasts.
BACKGROUND: Interstitial fibroblasts are central to the inflammatory response during the progression of tubulointerstitial fibrosis. We examined the efficiency of a new gene transfer method that targets interstitial cells by using parenchymal injection of DNA followed by electroporation. METHODS:Fluoresceinisothiocyanate-labelled oligodeoxynucleotides (FITC-ODNs) or expression vectors were directly injected into the cortex of the kidney, followed by electroporation. RESULTS: Transfection with FITC-ODNs or the EGFP expression vector resulted in efficient transfection in interstitial fibroblasts, but not in tubular epithelial cells or glomerular cells. Transfection efficiency was optimal after using a total of 150 microg of DNA in 1000 microl of PBS, combined with clamping of the renal vessels prior to electroporation. Gene expression peaked at 4 days after transfection and decreased by two orders of magnitude at 6 weeks post-transfection; however, expression recovered to near peak levels after parenchymal or intraperitoneal injection of FR901228, a histone deacetylase inhibitor. CONCLUSION: We demonstrated that direct parenchymal injection of DNA combined with electroporation enables gene transfer into interstitial fibroblasts.