Gene therapy directed to the kidney has been attempted to improve renal disorders such as inherited
kidney diseases and common renal diseases that cause interstitial
fibrosis, tubular
atrophy, and glomerulosclerosis. Viral and non-viral vectors have been tried and been modulated to obtain sufficient transgene expression. However, gene delivery to the kidney is usually difficult because of characteristics of renal cell biology. Among non-viral vectors, the
liposome system is a promising procedure for kidney-targeted gene therapy. Using cationic
liposome, tubular cells were effectively transduced by retrograde injection of
liposome/
cDNA complex. Although transgene expression was reportedly modest using cationic
liposomes, this method improved renal disease models such as
carbonic anhydrase II deficiency and unilateral
ureteral obstruction. In contrast, HVJ-
liposome system is an effective transfection method to glomerular cells using intra-renal arterial infusion and improved glomerular disease models such as
glomerulonephritis and glomerulosclerosis. In addition, intra-renal pelvic injection of
DNA by HVJ-
liposome system showed transgene expression in interstitial fibroblasts. In kidney-targeted gene therapy,
liposome-mediated gene transfer is an attractive method because of its simplicity and reduced toxicity. In spite of modest transgene expression, several renal disease models were successfully modulated by
liposome system. Although one limitation of
liposome-mediated gene delivery is the duration of transgene expression, the
liposome/
cDNA complex can be repeatedly administered due to the absence of an immune response.