255. Simultaneous Administration of Cell Therapy with ADSCs and Gene Therapy Using Ad-huPA Reduces Experimental Liver Fibrosis

Abstract

BACKGROUND: In experimental models of cirrhosis cell therapy with hADSCs (adipose derived stromal cells) has improved liver function while reduced fibrotic tissue. Also, gene therapy using Ad-huPA has diminished liver fibrosis and increased hepatocyte regeneration. The aim of this study was to evaluate if the simultaneous administration of these therapies presents an enhanced antifibrogenic effect in cirrhotic rats.METHODS: hADSCs were isolated from fat tissue, expanded and characterized by expression of CD105+, CD73+, HLA-ABC+, CD45-, CD34-, HLA-DRII- markers and osteogenic and adipogenic differentiation. Ad-huPA vector was generated by recombination of pMH4-huPA and pJM17ΔE1 Ad-v backbone. CCl4-cirrhotic rats were administered with hADSCs (2X106 cells/rat) or Ad-huPA (3×1011 vp/rat) or both hADSCs/Ad-huPA via ileac vein. 24 hours before initiating treatment all groups were immunosuppressed with 10mg/kg of Cyclosporine A until sacrifice. After 10 days, percentage of fibrotic tissue, collagen fiber staining and mRNA levels of TGF-b1, collagen a1, CTGF, PAI-I and α-SMA were evaluated. Besides, serum levels of ALT, AST and albumin, biodistribution of hADSCs and liver levels of huPA protein were examined.RESULTS: Detection of the DAPI signal revealed that hADSCs mainly homing in liver and few of them were arrested in lung and spleen. Administration of hADSCs, Ad-huPA and Ad-huPA/hADSCs reduces (p<0.01) liver fibrosis in 78.9%, 65.2% and 72% respectively; and diminishes Collagen a1, CTGF and α-SMA mRNA liver levels (p<0.05). Furthermore, TGF-b1 and PAI-I liver mRNA levels (p<0.05) decrease in animals treated with Ad-huPA and hADSCs. Serum levels of albumin increase in the Ad-huPA, hADSCs and Ad-huPA/hADSCs groups (p<0.05) compared with control group. ALT and AST serum levels showed a significant diminish in hADSCs group (p<0.05). huPA protein was expressed in similar levels in liver homogenates of Ad-huPA and Ad-huPA/hADSCs groups. hADSCs, Ad-huPA and hADSC/Ad-huPA administration reduce percentage of collagen staining 4.3, 2.4 and 2.7 fold (p£0.001), respectively.CONCLUSIONS: Xenogenic hADSCs, Ad-huPA and Ad-huPA/hADSCs therapies decreased liver fibrosis and expression of pro-fibrogenic molecules in CCl4-cirrhotic animals. However, simultaneous administration of cell therapy and gene therapy does not appear to improve antifibrogenic effects of individual treatments.