A comparative analysis of acellular versus red cell based subnormothermic machine perfusion in human kidney transplantation

Subnormothermic machine perfusion (SMP, 32°C) may reduce metabolic demands while preserving organ viability, but the effect of perfusate type under these conditions remains unclear. In a paired experimental design, kidneys from eight deceased donors were randomized 1:1 to 6 hours of SMP with RBC-based (RBC-SMP) or acellular perfusate (SNAP), followed by 4 hours of RBC-based NMP (37°C) to simulate reperfusion.

Upregulation of transcriptomic ischaemia-reperfusion injury (IRI) related pathways and downregulation of oxidative phosphorylation at 6 hours SMP and 4 hours reperfusion were similar between RBC-SMP and SNAP kidneys. No differences were observed between groups in transcriptional profiles, metabolic pathway scores, urinary tubular injury biomarker concentrations, or histology. We integrated publicly available NMP transcriptomic data for comparison, demonstrating that compared to 6 hours RBC-NMP at 37°C, both SMP groups showed equivalent pro-inflammatory pathway activation and oxidative phosphorylation depletion.