Oral communications

Ischemia reperfusion (IR) injury is unavoidable during organ transplantation and leads to complications. With the increased use of marginal donors, more sensitive to IR, solutions must be found to improve outcome. We hypothesized that a higher preservation temperature could offer better protection against IR.[br/]Methods: We tested this in an in vitro model of IR using primary endothelial cells and in ex vivo preserved pig kidneys. In both, 24 h preservation in University of Wisconsin solution was used.[br/]Results: In vitro, compared to 4°C, temperatures between 19 and 32°C provided higher protection against cell death (LDH release test), permitting better mitochondrial function (complexes II and V activity tests) and a lowerexpression of endothelial activation and inflammation markers TLR4, MCP1 and ICAM1. Ex vivo, however, the superiority of 19 or 32°C was lost, as preserved pig kidneys showed similar levels of tissue damage (both tubulardilatation, loss of brush border and endoluminal detachment) during preservation, and at 24 h the 4°C kidneys displayed a trend towards less damage. In addition, the tissular Monocyte/Macrophage infiltration was increased in the 19°C and more in the 32°C temperature conservation as compared to 4°C storage.[br/]Conclusion: Our study shows that although a higher preservation temperature is preferable for cell survival and function, whole organ testing demonstrates that conceptual work needs to be performed to harness the potential of sub-normothermia