Expression of hypoxia-inducible factor-1α and hepatocyte growth factor in development of fibrosis in the transplanted kidney.

Abstract

Late renal graft loss is associated with interstitial fibrosis. Hypoxia-inducible factor-1α (HIF-1α) is thought to facilitate fibrosis through interaction with TGF-β1, while hepatocyte growth factor (HGF) may act antifibrotic in the kidney allograft. The aim of this study was to investigate the expression of HIF-1α and HGF in protocol biopsies as possible prognostic biomarkers for renal fibrosis. Thirty-nine renal transplant recipients were included in the study. Protocol biopsies performed 1 and 2years after transplantation were used for immunohistochemistry analysis. The correlation between HIF-1α/HGF and the Banff score was analysed. In addition, progression in renal fibrosis and graft survival among recipients with high or low expression of HIF-1α/HGF after transplantation was compared. There was no significant correlation between fibrosis and the HIF-1α expression 1 and 2years after transplantation, but an inverse significant correlation between the HGF expression and the fibrosis score 1year after transplantation was shown. Even when adjusting for human leucocyte antigen mismatches, there was a significant relationship between fibrosis and HGF expression. Graft survival was not significantly correlated to HIF-1α or HGF at 1year, although the trend was towards better graft survival with high HGF. HGF may have antifibrotic effects in human renal transplants. (Central.Denmark.Region.Committee number: 1-10-72-318-13).