P1687ASSOCIATION OF URINARY MICRORNA-21-5P WITH INTERSTITIAL FIBROSIS AND TUBULAR ATROPHY (IFTA) IN RENAL TRANSPLANT RECIPIENTS

Abstract

Abstract Background and Aims One of the most limiting factors of long-term graft survival is chronic renal allograft dysfunction (CAD). The major hallmarks of CAD are interstitial fibrosis and tubular atrophy (IFTA). MicroRNAs (miRNAs) are 19-25 nucleotides, small, noncoding molecules involved in the regulation of gene expression. MiRNAs have a role in various immunological processes, including inflammation and fibrosis. Particularly, microRNA-21-5p (miR-21) is reported to be strongly associated with pathogenesis regarding tubulointerstitium. The aim of this study was to analyse expression levels of urinary miR-21 in the renal transplant recipients and evaluate their application in the assessment of IFTA and kidney allograft function. Method The expression levels of urinary miR-21 were measured in 31 renal transplant recipients with biopsy-evaluated IFTA (IFTA 0+I: n=17; IFTA II+III: n=14) by quantitative PCR. Protocolar biopsies were performed 1 or 2 years after renal transplantation. Urine samples were collected at the time of biopsy procedure. MicroRNA-191-5p was used as reference gene. Correlations between the clinicopathological parameters and the level of expression of miR-21 were assessed. Results Relative expression level of miR-21 was significantly increased in IFTA II+III group compared to IFTA 0+I group. MiR-21 correlated positively with serum concentration of creatinine and negatively with eGFR. ROC analysis showed diagnostic value of miR-21 with an area under curve (AUC) of 0.80, high sensitivity and specificity. Conclusion MiR-21 is associated with IFTA and dysfunction of kidney allograft. It may be considered as potential non-invasive biomarker of renal allograft function.