Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 21, 2015; 21(23): 7165-7171
Published online Jun 21, 2015. doi: 10.3748/wjg.v21.i23.7165
Activated rat hepatic stellate cells influence Th1/Th2 profile in vitro
Zhi-Zhi Xing, Liu-Ye Huang, Cheng-Rong Wu, Hong You, Hong Ma, Ji-Dong Jia
Zhi-Zhi Xing, Liu-Ye Huang, Cheng-Rong Wu, Department of Gastroenterology, Yantai Yuhuangding Hospital Affiliated to Medical College of Qingdao University, Yantai 264000, Shandong Province, China
Hong You, Hong Ma, Ji-Dong Jia, Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
Author contributions: Xing ZZ and Jia JD designed the research; Xing ZZ, Huang LY, Wu CR and Ma H performed the research; Jia JD and You H contributed new reagents/analytical tools; Huang LY and You H analyzed the data; and Xing ZZ, You H and Jia JD wrote the paper; all the authors approved the final version of the manuscript.
Supported by Major State Basic Research Development Program of China, No. 2007CB512802; and the National Natural Science Foundation of China, No. 30500425.
Ethics approval: The study was reviewed and approved by the Yan Tai Yu Huang Ding Hospital Review Board.
Institutional animal care and use committee: All animal experiments were carried out in accordance with the National Institute of Health Guide for the Care and Use of Laboratory Animals and approved by the Institutional Animal Care and Use Committee of China Academy of Chinese Medical Sciences.
Conflict-of-interest: The authors declare that they have no conflicts of interest to this work.
Data sharing: No additional data are available.
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: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Ji-Dong Jia, MD, PhD, Liver Research Center, Beijing Friendship Hospital, Capital Medical University, 95 Yong-an Road, Xicheng District, Beijing 100050, China. jiamd@263.net
Telephone: +86-10-63138727 Fax: +86-10-83165944
Received: October 29, 2014
Peer-review started: October 30, 2014
First decision: December 11, 2014
Revised: January 8, 2015
Accepted: April 9, 2015
Article in press: April 9, 2015
Published online: June 21, 2015
Processing time: 233 Days and 19.2 Hours
Abstract

AIM: To investigate the effects of activated rat hepatic stellate cells (HSCs) on rat Th1/Th2 profile in vitro.

METHODS: Growth and survival of activated HSCs and CD4+ T lymphocytes cultured alone or together was assessed after 24 or 48 h. CD4+ T lymphocytes were then cultured with or without activated HSCs for 24 or 48 h and the proportion of Th1 [interferon (IFN)-γ+] and Th2 [interleukin (IL)-4+] cells was assessed by flow cytometry. Th1 and Th2 cell apoptosis was assessed after 24 h of co-culture using a caspase-3 staining procedure. Differentiation rates of Th1 and Th2 cells from CD4+ T lymphocytes that were positive for CD25 but did not express IFN-γ or IL-4 were also assessed after 48 h of co-culture with activated HSCs. Galectin-9 expression in HSCs was determined by immunofluorescence and Western blotting. ELISA was performed to assess galectin-9 secretion from activated HSCs.

RESULTS: Co-culture of CD4+ T lymphocytes with activated rat HSCs for 48 h significantly reduced the proportion of Th1 cells compared to culture-alone conditions (-1.73% ± 0.71%; P < 0.05), whereas the proportion of Th2 cells was not altered; the Th1/Th2 ratio was significantly decreased (-0.44 ± 0.13; P < 0.05). In addition, the level of IFN-γ in Th1 cells was decreased (-65.71 ± 9.67; P < 0.01), whereas the level of IL-4 in Th2 cells was increased (82.79 ± 25.12; P < 0.05) by co-culturing, as measured by mean fluorescence intensity by flow cytometry. Apoptosis rates in Th1 (12.27% ± 0.99%; P < 0.01) and Th2 (1.71% ± 0.185%; P < 0.01) cells were increased 24 h after co-culturing with activated HSCs; the Th1 cell apoptosis rate was significantly higher than in Th2 cells (P < 0.01). Galectin-9 protein expression was significantly decreased in HSCs only 24 h after co-culturing (P < 0.05) but not after 48 h. Co-culture for 48 h significantly increased the differentiation of Th1 and Th2 cells; however, the increase in the proportion of Th2 cells was significantly higher than that of Th1 cells (1.85% ± 0.48%; P < 0.05).

CONCLUSION: Activated rat HSCs lower the Th1/Th2 profile, inhibiting the Th1 response and enhancing the Th2 response, and this may be a novel pathway for liver fibrogenesis.

Keywords: Hepatic stellate cells; Th1 cells; Th2 cells; Galectin-9

Core tip: The Th1/Th2 profile plays a pivotal role in the development of fibrosis and may be impacted by hepatic stellate cell activation. However, little is known about the effect of fibroblasts on CD4+ T lymphocyte profiles. This study shows that co-culture with activated rat hepatic stellate cells shifts the Th1/Th2 profile of CD4+ T lymphocytes by inhibiting the Th1 response and enhancing the Th2 response.