Infusing Mesenchymal Stromal Cells into Porcine Kidneys during Normothermic Machine Perfusion: Intact MSCs Can Be Traced and Localised to Glomeruli

Abstract

Normothermic machine perfusion (NMP) of kidneys offers the opportunity to perform active interventions, such as the addition of mesenchymal stromal cells (MSCs), to an isolated organ prior to transplantation. The purpose of this study was to determine whether administering MSCs to kidneys during NMP is feasible, what the effect of NMP is on MSCs and whether intact MSCs are retained in the kidney and to which structures they home. Viable porcine kidneys were obtained from a slaughterhouse. Kidneys were machine perfused during 7 h at 37 °C. After 1 h of perfusion either 0, 105, 106 or 107 human adipose tissue derived MSCs were added. Additional ex vivo perfusions were conducted with fluorescent pre-labelled bone-marrow derived MSCs to assess localisation and survival of MSCs during NMP. After NMP, intact MSCs were detected by immunohistochemistry in the lumen of glomerular capillaries, but only in the 107 MSC group. The experiments with fluorescent pre-labelled MSCs showed that only a minority of glomeruli were positive for infused MSCs and most of these glomeruli contained multiple MSCs. Flow cytometry showed that the number of infused MSCs in the perfusion circuit steeply declined during NMP to approximately 10%. In conclusion, the number of circulating MSCs in the perfusate decreases rapidly in time and after NMP only a small portion of the MSCs are intact and these appear to be clustered in a minority of glomeruli.

Novel delivery of cellular therapy to reduce ischaemia reperfusion injury in kidney transplantation

“…This may be mirrored in our NMP model -MAPC cells are homing to hypoxic areas within a marginal kidney where they take temporary residence. In this environment, the cells release an anti-inflammatory secretome which is having beneficial effects, resulting in The findings of this study reflect similar work investigating pig kidneys treated with human mesenchymal stromal cells (MSC) during NMP 40,41 . These studies have similarly demonstrated tracked cells mainly localising to the glomeruli.…”

Reparative effect of mesenchymal stromal cells on endothelial cells after hypoxic and inflammatory injury

“…In addition, targeted delivery of MSC to the injured organ would be useful to improve their interplay with the injured tissue. Direct infusion through the renal artery and delivery during normothermic machine perfusion are plausible options to deliver cells specifically to the kidney and ensure MSC interaction with damaged renal endothelium during organ preservation [24].…”

“…A better understanding of these interactions will enable us to optimize the potential regenerative effect of MSC therapy on endothelial injury. The first data about MSC delivery to the kidney during ex situ normothermic machine perfusion show a distribution of MSC to the renal microvasculature, with MSC localizing to the renal cortex [24]. Although data suggest that MSC may possess renal regenerating effects after administration to the kidney [25], it is unknown whether this involves endothelial repair, and if so which mechanisms are involved.…”

Reparative Effect of Mesenchymal Stromal Cells on Endothelial Cells after Hypoxic and Inflammatory Injury

“…In addition, targeted delivery of MSC to the injured organ would be useful to improve their interplay with the injured tissue. Direct infusion through the renal artery or delivery during normothermic machine perfusion are plausible options to deliver cells speci cally to the kidney and ensure MSC interaction with damaged renal endothelium during the organ preservation (24).…”

“…A better understanding of these interactions will enable us to optimize the potential regenerative effect of MSC therapy on endothelial injury. The rst data about MSC delivery to the kidney during ex situ normothermic machine perfusion show a distribution of MSC to the renal microvasculature, with MSC localizing to the renal cortex (24). Although data suggest that MSC may possess renal regenerating effects after administration to the kidney (25), it is unknown whether this involves endothelial repair, and if so which mechanisms are involved.…”