Basic Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 21, 2022; 28(19): 2100-2111
Published online May 21, 2022. doi: 10.3748/wjg.v28.i19.2100
Ultrastructural changes in porcine liver sinusoidal endothelial cells of machine perfused liver donated after cardiac death
Hiroki Bochimoto, Yo Ishihara, Nur Khatijah Mohd Zin, Hiroyoshi Iwata, Daisuke Kondoh, Hiromichi Obara, Naoto Matsuno
Hiroki Bochimoto, Nur Khatijah Mohd Zin, Department of Cell Physiology, The Jikei University School of Medicine, Minato-ku 105-8461, Tokyo, Japan
Hiroki Bochimoto, Yo Ishihara, Hiromichi Obara, Naoto Matsuno, Department of Transplantation Technology and Therapeutic Development, Asahikawa Medical University, Asahikawa 078-8510, Hokkaido, Japan
Hiroyoshi Iwata, Naoto Matsuno, Department of Surgery, Asahikawa Medical University, Asahikawa 078-8510, Hokkaido, Japan
Daisuke Kondoh, Laboratory of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
Hiromichi Obara, Department of Mechanical Engineering, Tokyo Metropolitan University, Hachioji 192-0397, Tokyo, Japan
Author contributions: Bochimoto H and Ishihara Y contributed equally to this work; Bochimoto H, Obara H and Matsuno N designed and coordinated the study; Bochimoto H, Ishihara Y, Kondoh D, Obara H and Matsuno N performed the experiments, acquired and analyzed data; Bochimoto H, Ishihara Y, Mohd Zin NK, Iwata H, Kondoh D, Obara H and Matsuno N interpreted the data; Bochimoto H wrote the manuscript; all authors approved the final version of the article.
Supported by JSPS KAKENHI Grant, No. JP17K10503 (to Matsuno N) and JP20K11539 (to Bochimoto H).
Institutional review board statement: The study was reviewed and approved by the Institutional Animal Ethics Committee of the Clinical Research Center, Asahikawa Medical University.
Institutional animal care and use committee statement: All animal experiments conformed to the internationally accepted principles for the care and use of laboratory animals (permit No. 14172, The Institutional Animal Ethics Committee of the Clinical Research Center, Asahikawa Medical University, Asahikawa, Japan).
Conflict-of-interest statement: All of the authors have nothing to disclose.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hiroki Bochimoto, MD, PhD, Assistant Professor, Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi, Minato-ku 105-8461, Tokyo, Japan. botimoto@jikei.ac.jp
Received: May 19, 2021
Peer-review started: May 19, 2021
First decision: June 12, 2021
Revised: July 17, 2021
Accepted: April 3, 2022
Article in press: April 3, 2022
Published online: May 21, 2022
Processing time: 362 Days and 17.3 Hours
ARTICLE HIGHLIGHTS
Research background

Using liver grafts donated after cardiac death (DCD) is one way to solve the shortage of donors for liver transplantation. Machine perfusion (MP) preservation has been considered as a promising, and the optimal conditions of perfusion temperature of MP of the DCD grafts, including hypothermic MP (HMP) and midthermic MP (MMP) has been discussed.

Research motivation

Recent research showed the practicality of scanning electron microscopy after osmium-maceration (OM-SEM) with complementary transmission electron microscopy (TEM) in evaluating the function of the liver grafts which is reflected by ultrastructural characteristics of hepatocytes. This has prompted the application of this novel strategy for the evaluation of liver sinusoidal endothelial cells (LSEC) damage in regulating liver injury during MP.

Research objectives

The present study aimed to establish the usefulness of the OM-SEM with complementary TEM for the evaluation of LSEC damage, and comparatively investigate the ultrastructural changes associated with LSEC at 4 h after HMP or MMP.

Research methods

Female pigs were intubated and ventilated under anesthesia, and their liver tissues were biopsied immediately after laparotomy, as control, and 60 min of warm ischemia. The liver grafts which had warm ischemia of 60 min were perfused for 4 h with modified University of Wisconsin gluconate solution by HMP at 8 °C constantly or MMP rewarming up to 22 °C and biopsied at the endpoint of MP. the LSEC in all biopsied liver samples were analyzed by immunohistochemistry and OM-SEM with complementary TEM. The viability of LSEC in liver grafts preserved for 4 h was evaluated by hyaluronic acid levels in the perfusate.

Research results

Immunohistochemistry showed the interspersed viable ERG positive sinusoidal endothelial cells in all biopsied liver samples. After warm ischemia, the LSEC showed the mitochondria with condensed-shaped cristae, abnormal vesicles, reduction of ribosomes and the ER surrounding the mitochondria. Both the HMP and MMP after warm ischemia alleviate the ER damage in LSEC indicated by the abnormal vesicles and reduction of ribosomes. The value of HyA in the perfusate did not indicate a significant difference between HMP and MMP, although there was a trend of improvement in MMP, moreover, only MMP, not HMP, could restore the tubular cristae of mitochondria.

Research conclusions

This research confirmed the usefulness of the OM-SEM with complementary TEM for the evaluation of LSEC damage reflected on the ultrastructure of organelles. MP alleviate the ultrastructural abnormalities indicating ER damage of LSEC caused by warm ischemia. Moreover, MMP temperature conditions restore the metabolism of LSEC via the normalization of ultrastructural characteristics of cristae of mitochondria and prevent the damage of the liver graft by share stress.

Research perspectives

The OM-SEM with complementary TEM is applicable for the detailed evaluation of LSEC damage reflected on the ultrastructure of the MP of various conditions, including different temperatures during perfusion storage, for clinically application of the MP for liver transplantation.