189 - AP39 Mitigates the Effects of Normothermic Organ Preservation and Ex Vivo Renal Transplantation following Donation after Cardiac Death

Abstract

Background While cold storage of organs prior to transplantation is the clinical standard of care, it has been shown to exacerbate renal ischemia-reperfusion injury (IRI). Adding hydrogen sulfide (H2S) to cold University of Wisconsin (UW) solution has been shown to ameliorate graft function and injury. However, normothermic preservation alternatives are also of interest. In this study, we investigate the effect of normothermic preservation with UW solution containing a novel, mitochondria-targeted H2S donor (AP39) using a clinically relevant ex vivo porcine model of renal transplantation. Methods Warm ischemia was induced via 30m of renal pedicle clamping. The left kidney was flushed with and stored in cold UW solution for 4h. The right kidney was flushed with UW+200nM AP39 and then perfused ex vivo with non-stressed blood at 21°C for 4h. Both kidneys were then perfused with stressed blood at 37°C for 4h to simulate renal transplantation. Hourly urine and blood samples were analyzed. Tissue injury was evaluated using histopathology. Results Kidneys treated with UW+AP39 had greater mean total urine output compared to UW preserved kidneys. UW+AP39 kidneys also showed lower mean urine protein excretion compared to the UW only kidneys, suggestive of diminished glomerular injury. Histopathological data supported these findings. Conclusion We demonstrate, for the first time, that normothermic preservation with AP39-supplemented UW solution leads to superior graft function and reduced tissue injury compared to the current standard of clinical care.