Partial decellularization of kidneys during prolonged acellular perfusion

Long-term ex situ machine perfusion of donor organs is an emerging clinical strategy that creates a window for advanced therapeutic interventions. Replacing donor endothelial cells during machine perfusion with recipient endothelium could conceal the allogeneic epithelium from the recipients (humoral) immune response. We postulated that brief exposure to low concentrations of decellularizing agents could selectively remove vascular endothelium. Porcine kidneys were partially decellularized with five 2-minute infusions of either 0.01%, 0.1% or 1.0% SDS during acellular perfusion. As proof-of-concept, fluorescently-labelled porcine endothelial colony forming cells (ECFCs) were infused into the renal vein and artery of a partially decellularized kidney. Tissue analysis identified 0.1% SDS effectively removed endothelial cells from glomerular and peritubular capillaries. Infused ECFCs could be found back within the glomeruli. However, partial decellularization significantly impaired renal flow and increased vascular resistance. While partial decellularization successfully removed donor endothelium, the loss of vascular patency limits its clinical potential. Future research should prioritize modifying rather than removing donor endothelial cells.