Korean J Transplant.  2022 Nov;36(Supple 1):S19. 10.4285/ATW2022.F-1014.

Visualization of ischemia reperfusion injury of kidney and prediction of early allograft dysfunction after kidney transplantation using cysteine probe

• Woo HY
• Min Si
• Han A
• Ha J

• KMID: 2535135
• DOI: http://doi.org/10.4285/ATW2022.F-1014

Abstract

Background
In kidney transplantation (KT), ischemia-reperfusion injury (IRI) of the transplanted kidney inevitably occurs through a series of processes, especially from deceased donors. About 20%–30% of early graft failure is caused by this IRI. In order to prevent and minimize IRI, it is important to develop a model evaluating the presence and severity of IRI. However, ade-quate markers for kidney injury are not clear. In this study, we suggest the new diagnostic model for kidney injury and verified its effectiveness.
Methods
A new diagnostic method was introduced using the molecular probe NPO-B, which selectively responds to cysteine and exhibits fluorescence. To confirm the efficacy of the NPO-B probe, human kidney-2 cells IRI model in vitro and mouse IRI model in vivo was established. In addition, we compared the predictive capacity for posttransplant early allograft dysfunction between convention factors without urine cysteine and with urine cysteine using the area under the curve (AUC) in 91 KT recip-ients.
Results
In vitro model, an increased expression of cystathionine-gamma-lyase was observed in the IRI-treated cell group us-ing Western blot. In the mouse IRI model, dose-dependent increases in NPO-B fluorescence according to ischemia time in both methods including NPO-B injection and NPO-B soaking method was confirmed by using FITS and two-photon microscopy (TPM) (Fig. 1). Cysteine was measured well with NPO-B in mouse urine, and it was confirmed that the predictive power to pre-dict immediate posttransplant graft dysfunction with patient urine was improved by adding urine cysteine to the conventional factors (AUC, 0.82 vs. 0.79).
Conclusions
A method to identify and visualize the severity of IRI with cysteine detection using NPO-B was introduced. If this is applied to clinical practice in the future, it is expected to be used to determine the severity of IRI at the time of organ procurement or reperfusion from the deceased donors.