Dose‐Ranging Study of the Performance of the Natural Oxygen Transporter HEMO 2 L ife in Organ Preservation

The intensity of ischemia–reperfusion injury of the donor organ during the preservation phase and after anastomosis is acknowledged as being a key factor for long‐term graft outcome. We previously showed that the addition of 5  g/L of the natural oxygen carrier HEMO 2 L ife was beneficial for the cold static preservation of kidney grafts in both University of Wisconsin ( UW ) and histidine–tryptophan–ketoglutarate solutions. Herein, we refined these findings by evaluating HEMO 2 L ife at various dose levels in UW , both in vitro with endothelial cells and in vivo in a pig kidney autotransplantation preclinical model. We showed in vitro that cells were significantly better preserved with HEMO 2 L ife in a dose‐dependent manner, with benefits in terms of survival, metabolic activity, and cellular integrity. In vivo, serum creatinine measurements at reperfusion confirmed the important benefits of HEMO 2 L ife treatment on function recovery at the dose levels of 1, 2, and 5  g/L . Likewise, histological analysis of kidney parenchyma biopsies from day 7 confirmed the superiority of HEMO 2 L ife‐supplemented UW over UW alone, and there was no difference between the doses. Three months' follow‐up confirmed the trend of the first 2 weeks, with creatinine and fibrosis levels similar to those in pretransplant kidneys.