O45: DEFINING CELL-ENRICHED MICRORNAS TO SUPPORT RATIONAL BIOMARKER SELECTION IN HUMAN RENAL TRANSPLANTATION

Abstract Introduction MicroRNAs are promising biomarkers of renal disease, however the cellular origin their expression is usually unclear limiting interpretation when measured in biopsies and urine. We hypothesised that by first defining cell-enriched microRNAs, we could select based on expected histopathological profile. Method Small RNA-sequencing cortical, proximal tubular (LTL), macrophage (F480), endothelial (CD31) fibroblast (PDGFRb) populations from reversible unilateral ureteric obstruction (rUUO) murine model was performed. Hierarchical clustering used to identify clusters. Findings were translated into an ischaemia reperfusion injury (IRI) then urine samples transplant recipients (n=16) with delayed graft function (DGF) vs. those primary function. Result Kidney resulted significant infiltration which improved upon reversal. characterised novel microRNA clusters enriched for each cell type. With there a increase (p<0.0001), (p<0.01) decrease tubule (p<0.0001) microRNAs non-enriched microRNAs. validated miR-18a, miR-16 miR-194 IRI model, demonstrating reflected histological In humans, urinary (FC 16.9; p<0.05) miR-18a 10: p=0.06) upregulated at day 2 patients DGF; outperforming traditional marker KIM1. Conclusion This study characterise during repair. By source able rationally as injury. Take-home message have found differences between types states important considering composed varying composition. origins human