Basic Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 7, 2017; 23(45): 7989-7999
Published online Dec 7, 2017. doi: 10.3748/wjg.v23.i45.7989
Improved experimental model of hepatic cystic hydatid disease resembling natural infection route with stable growing dynamics and immune reaction
Rui-Qing Zhang, Xin-Hua Chen, Hao Wen
Rui-Qing Zhang, Hao Wen, Hepatobiliary and Hydatid Department, Digestive and Vascular Surgery Centre, Xinjiang Key Laboratory of Echinococcosis, The First Affiliated Hospital of Xinjiang Medical University, Urumqi 830011, Xinjiang Uygur Autonomous Region, China
Xin-Hua Chen, Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University, Hangzhou 310000, Zhejiang Province, China
Xin-Hua Chen, Key Laboratory of Combined Multi-organ Transplantation, Ministry of Public Health, The First Affiliated Hospital, Zhejiang University, Hangzhou 310000, Zhejiang Province, China
Xin-Hua Chen, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University, Hangzhou 310000, Zhejiang Province, China
Author contributions: Chen XH designed the study; Wen H supervised and coordinated the study; Zhang RQ collected the samples and performed the follow-up; Chen XH drafted the manuscript; all authors reviewed and approved the final manuscript.
Supported by Xinjiang Key Lab of Xinjiang Science and Technology Bureau Xinjiang, No. 2014KL002; National Natural Science Foundation of China, No. 81372425; National S&T Major Project, No. SQ2018ZX100301.
Institutional review board statement: This study was approved by the Institutional Review Board of The First Affiliated Hospital of Xinjiang Medical University.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of The First Affiliated Hospital of Xinjiang Medical University (IACUC protocol number: 20141217003).
Conflict-of-interest statement: No potential conflicts of interest relevant to this article are reported.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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:
Correspondence to: Xin-Hua Chen, MD, PhD, Department of Hepatobiliary and Pancreatic Surgery, First Affiliated Hospital, Zhejiang University, 79 Qingchun Road, Hangzhou 310003, Zhejiang Province, China.
Telephone: +86-571-87236570 Fax: +86-571-87236466
Received: July 21, 2017
Peer-review started: July 24, 2017
First decision: August 30, 2017
Revised: October 6, 2017
Accepted: October 17, 2017
Article in press: October 17, 2017
Published online: December 7, 2017
Research background

Hydatid disease is caused by Echinococcus granulosus. It is a worldwide zoonosis. It is highly prevalent in Xinjiang, China. The animal disease model is of great significance for the drug development against parasite disease.

Research motivation

Echinococcosis is mostly caused by close contact with infected dogs or occupational exposures. The researchers producing hydatid disease model have the high risk of infection because they handle parasite eggs to feed animals through oral route.

Research objectives

To avoid contamination risk of handling parasite eggs, this study investigated a safer way for developing an experimental murine model of cystic echinococcosis in the liver.

Research methods

Bypassing the oral feeding of contaminant parasite eggs, human protoscolices were injected via the portal vein. Using this method, the tapeworm eggs that may contaminate lab and consequently enable transmission to human beings are avoided.

Research results

The pathological results confirmed that protoscolices kept alive and moved from the portal vein into different liver segments and lobes, and the three different protoscolice injection concentrations led to different infection rates of 90%, 100%, and 63.6%, respectively.

Research conclusions

By sterile injection with human protoscolices via the portal vein, a novel murine model was developed with echinococcosis vacuoles formed in the liver. Without contamination risk to researchers, this disease model is suitable for anti-hydatid treatment trials.

Research perspectives

The good experience that can be learnt from this study is the portal vein injection, which can bypass the oral feeding with parasite eggs. The protoscolices migrate in the portal vein with blood flow, settle in the liver, and develop into orthotopic hepatic hydatid cysts, resembling the natural infection route and course. The lesson that can be learnt from this study is protoscolex collection. Only the fresh protoscolex can result in success parasite growth.

With this model, the further anti-hydatid medicines and interventional treatment can be tried. With the quantitative immune results, the effects can be monitored by blood test.

Using standard score calculated as (raw score - mean)/SD, the best injection method has been screened. This value allows comparisons to be made between the three models with different distribution characteristics. The portal vein injection at 200 protoscolices in 100 μL saline is the best method for the future model.