Normothermic ex vivo kidney perfusion for graft quality assessment prior to transplantation

AbstractNormothermic ex-vivo kidney perfusion (NEVKP) results in significantly improved graft function in porcine auto-transplant models of DCD injury compared to static cold storage (SCS); however, the molecular mechanisms underlying these beneficial effects remain unclear. We performed an unbiased proteomics analysis of 28 kidney biopsies obtained at 3 time points from pig kidneys subjected to 30-minutes of warm ischemia, followed by 8 hours of NEVKP or SCS, and auto-transplantation. 70/6593 proteins quantified were differentially expressed between NEVKP and SCS groups (FDR<0.05). Proteins increased in NEVKP mediated key metabolic processes including fatty acid ß-oxidation, the TCA-cycle and oxidative phosphorylation. Comparison of our findings with external datasets of ischemia-reperfusion, and other models of kidney injury confirmed that 47 of our proteins represent a common signature of kidney injury reversed or attenuated by NEVKP. We validated key metabolic proteins (ETFB, CPT2) by immunoblotting. Transcription factor databases identified PPARGC1A, PPARA/G/D and RXRA/B as the upstream regulators of our dataset, and we confirmed their increased expression in NEVKP with RT-PCR. The proteome-level changes observed in NEVKP mediate critical metabolic pathways that may explain the improved graft function observed. These effects may be coordinated by PPAR-family transcription factors, and may represent novel therapeutic targets in ischemia-reperfusion injury.

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Kidney Perfusion as an Organ Quality Assessment Tool—Are We Counting Our Chickens Before They Have Hatched?

Journal of Clinical Medicine ◽

10.3390/jcm9030879 ◽

2020 ◽

Vol 9 (3) ◽

pp. 879 ◽

Cited By ~ 2

Author(s):

Julie De Beule ◽

Ina Jochmans

Keyword(s):

Quality Assessment ◽

Assessment Tool ◽

Assessment Tools ◽

Ex Situ ◽

Risk Scores ◽

Final Decision ◽

Kidney Graft ◽

Viability Assessment ◽

Organ Quality ◽

Kidney Perfusion

The final decision to accept an organ for transplantation remains a subjective one. With “poor organ quality” commonly cited as a major reason for kidney discard, accurate, objective, and reliable quality assessment is essential. In an era of increasingly higher-risk deceased donor kidneys, the catch is to accept those where the risk–benefit scale will tip in the right direction. Currently available assessment tools, such as risk-scores predicting outcome and zero-time biopsy, perform unsatisfactory, and assessment options during static cold storage are limited. Kidney perfusion technologies are finding their way into clinical practice, and they bring a new opportunity to assess kidney graft viability and quality, both in hypothermic and normothermic conditions. We give an overview of the current understanding of kidney viability assessment during ex situ kidney perfusion. A pragmatic framework to approach viability assessment is proposed as an interplay of three different compartments: the nephron, the vascular compartment, and the immune compartment. Although many interesting ways to assess kidney injury and function during perfusion have been proposed, none have reached the stage where they can reliably predict posttransplant outcome. Larger well-designed studies and validation cohorts are needed to provide better guidance.

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Graft quality assessment in kidney transplantation: not an exact science yet!

Current Opinion in Organ Transplantation ◽

10.1097/mot.0b013e3283446b31 ◽

2011 ◽

Vol 16 (2) ◽

pp. 174-179 ◽

Cited By ~ 43

Author(s):

Ina Jochmans ◽

Jacques Pirenne

Keyword(s):

Kidney Transplantation ◽

Quality Assessment ◽

Exact Science ◽

Graft Quality

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Brain Graft Quality Assessment By Evaluation Of The Geometry Of Its Computer Reconstruction

Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society Volume 13: 1991 ◽

10.1109/iembs.1991.684439 ◽

2005 ◽

Author(s):

I. Krokule ◽

R. Palovsky ◽

K. Gronychova ◽

L. Kubinova ◽

V. Valoubkova ◽

...

Keyword(s):

Quality Assessment ◽

Computer Reconstruction ◽

Graft Quality

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Stroma-Contact Prevents Loss of Hematopoietic Stem Cell Quality During Ex Vivo Expansion of CD34+ Mobilized Peripheral Blood Stem Cells

Blood ◽

10.1182/blood.v91.1.111.111_111_117 ◽

1998 ◽

Vol 91 (1) ◽

pp. 111-117 ◽

Cited By ~ 5

Author(s):

Dimitri A. Breems ◽

Ellen A.W. Blokland ◽

Karen E. Siebel ◽

Angelique E.M. Mayen ◽

Lilian J.A. Engels ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Ex Vivo ◽

Peripheral Blood Stem Cells ◽

Soluble Factors ◽

Hematopoietic Stem ◽

Blood Stem Cells ◽

Ex Vivo Culture ◽

Mobilized Peripheral Blood ◽

Graft Quality

Stroma-supported long-term cultures (LTC) allow estimation of stem cell quality by simultaneous enumeration of hematopoietic stem cell (HSC) frequencies in a graft using the cobblestone area forming cell (CAFC) assay, and the ability of the graft to generate progenitors in flask LTC (LTC-CFC). We have recently observed that the number and quality of mobilized peripheral blood stem cells (PBSC) was low in patients having received multiple rounds of chemotherapy. Moreover, grafts with low numbers of HSC and poor HSC quality had a high probability to cause graft failure upon their autologous infusion. Because ex vivo culture of stem cells has been suggested to present an attractive tool to improve hematological recovery or reduce graft size, we have studied the possibility that such propagation may affect stem cell quality. In order to do so, we have assessed the recovery of different stem cell subsets in CD34+ PBSC after a 7-day serum-free liquid culture using CAFC and LTC-CFC assays. A numerical expansion of stem cell subsets was observed in the presence of interleukin-3 (IL-3), stem cell factor, and IL-6, while stroma-contact, stromal soluble factors, or combined addition of FLT3-ligand and thrombopoietin improved this parameter. In contrast, ex vivo culture severely reduced the ability of the graft to produce progenitors in LTC while stromal soluble factors partly abrogated this quality loss. The best conservation of graft quality was observed when the PBSC were cultured in stroma-contact. These data suggest that ex vivo propagation of PBSC may allow numerical expansion of various stem cell subsets, however, at the expense of their quality. In addition, cytokine-driven PBSC cultures require stroma for optimal maintenance of graft quality.

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Significant Dysfunction of Kidney Grafts Exposed to Prolonged Warm Ischemia Is Minimized Through Normothermic Ex Vivo Kidney Perfusion

Transplantation Direct ◽

10.1097/txd.0000000000001030 ◽

2020 ◽

Vol 6 (8) ◽

pp. e587

Author(s):

Peter Urbanellis ◽

Dagmar Kollmann ◽

Ivan Linares ◽

Sujani Ganesh ◽

Fabiola Oquendo ◽

...

Keyword(s):

Ex Vivo ◽

Warm Ischemia ◽

Kidney Perfusion

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Ex vivo analysis of graft viability using 31P magnetic resonance imaging spectroscopy

British Journal of Surgery ◽

10.1093/bjs/znab202.083 ◽

2021 ◽

Vol 108 (Supplement_4) ◽

Author(s):

A Longchamp ◽

A Klauser ◽

T Agius ◽

J Songeon ◽

A Nastasi ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Ex Vivo ◽

High Energy ◽

Warm Ischemia ◽

Kidney Graft ◽

Resonance Imaging ◽

Atp Levels ◽

Kidney Perfusion ◽

Circulatory Death

Abstract Objective Expansion in organ supply has been proposed through the use of organs after circulatory death (donation after circulatory death [DCD]) in order to face the chronic shortage of kidneys for transplantation. However, many DCD grafts are discarded because of long warm ischemia times, and the absence of reliable non-invasive means to determine kidney viability. P magnetic resonance imaging (pMRI) spectroscopy is a noninvasive method to detect high-energy phosphate metabolites, such as ATP. However, the reliability of pMRI to predict kidney energy state, and its viability before transplantation remain also unknown. Methods To mimic DCD, pig kidneys underwent 0, 30 min or 60 min of warm ischemia, before oxygenated hypothermic machine perfusion (HMP). During the ex vivo perfusion, we assessed energy metabolites and Gadolinium elimination using pMRI. Each sample underwent histopathological scoring. Results Using pMRI, we found that in pig kidney, ATP was rapidly generated in presence of oxygen (100 kPa), which remained stable up to 22 h. Warm ischemia (60 min) induced significant histological damages, delayed cortical and medullary Gadolinium elimination (perfusion), and reduced ATP levels, but not its precursors (AMP). Finally, ATP levels and kidney perfusion both inversely correlated with the severity of kidney histological injury. Conclusion ATP levels, and kidney perfusion measurements using pMRI, are biomarkers of kidney injury after warm ischemia. Future work will define the role of pMRI in predicting kidney graft viability and patient's survival.

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