Bone marrow mesenchymal stem cells combine with normothermic machine perfusion to improve rat donor liver quality\u2014the important role of hepatic microcirculation in donation after circulatory death

Liu Yang,Bin Hou,Dong Sun,Ling Lin,Hong-Li Song,Zhong-Yang Shen,Huan Cao

doi:10.1007/s00441-020-03202-z

Abstract

Donation after circulatory death (DCD) can expand the donor pool effectively. A gap remains in outcome between DCD livers and living donor livers, warranting improved DCD liver quality and urgent resolution. Bone marrow mesenchymal stem cells (BMMSCs) can regulate immunity, participate in the anti-inflammatory response, and secrete cytokines. We investigated the effect of BMMSCs combined with normothermic machine perfusion (NMP) on DCD liver quality, and the role of microcirculation therein. Rat thoracic aortas were clipped to obtain DCD livers, and a rat NMP system was established. The DCD livers were grouped by preservation method: normal, static cold storage (SCS), NMP (P), and BMMSCs plus NMP (BP); storage time was up to 8 h. Liver function in outflow perfusate was detected by biochemical methods; liver tissue histopathology was observed by hematoxylin–eosin staining; hepatocyte ultrastructure was observed by transmission electron microscopy; hepatocyte apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling; liver microcirculation–related indicators were detected by immunofluorescence, immunohistochemistry, Western blotting, and enzyme-linked immunosorbent assay. Compared with SCS, P and BP significantly improved liver function and liver histological damage, reduced hepatocyte apoptosis, and repaired hepatocyte mitochondrial damage after 6 h in vitro. BP also significantly inhibited intrahepatic macrophage activation and intercellular adhesion, improved endothelial damage, and significantly improved endothelin 1–nitric oxide balance and microcirculation perfusion. In conclusion, BP can improve DCD liver microcirculation and quality. The mechanism may be the improvement of improve hepatic sinusoidal endothelial injury and microcirculation perfusion by inhibiting macrophage activation and intercellular adhesion.

Highlights

Materials and methodsLiver transplantation is the only effective treatment for endstage liver disease
Flow cytometry showed that the ratio of CD29+CD34− cells, CD90+CD45− cells, and RT1A+RT1B− cells was 99.5%, 98.7%, and 99.7%, respectively, indicating that the passage 3 Bone marrow mesenchymal stem cells (BMMSCs) were of high purity
We evaluated the influences of Normothermic machine perfusion (NMP)-alone preservation and that of BMMSCs plus NMP on donation after circulatory death organs (DCD) liver quality, and found that for perfusion of up to 6 h, BMMSCs plus NMP was significantly better than NMP alone for improving liver function, promoting lactate clearance, and bile production, significantly improving liver pathology and ischemia–reperfusion injury (IRI), and reducing hepatocyte apoptosis

Summary

Introduction

Materials and methodsLiver transplantation is the only effective treatment for endstage liver disease (de Haas et al 2018). To expand the donor pool, the use of extended criteria donors has increased (Manyalich et al 2018), including donation after circulatory death organs (DCD), which has become an effective means of expanding the donor pool and is currently a research hotspot on donor issues (Yeh and Uygun 2019). DCD livers experience longer periods of warm ischemia and ischemia–reperfusion injury (IRI) compared with donation after brain death (DBD) livers. Normothermic machine perfusion (NMP) can simulate the normal metabolic state in vivo, can reveal the quality of the liver by assessing bile production and lactate clearance, and store and repair donor livers. NMP has strong advantages for storing high-risk and marginal donor livers, and increases the use of donor livers effectively, which is promising for donor pool expansion (Laing et al 2017b; Watson et al 2017)

Results

Discussion

Conclusion