期刊
JOURNAL OF HEPATOLOGY
卷 62, 期 2, 页码 398-404出版社
ELSEVIER
DOI: 10.1016/j.jhep.2014.08.038
关键词
Hepatitis C virus; Regulatory CD4(+) T lymphocytes; NK cells; Hepatic stellate cells; Fibrogenesis
资金
- German Centre of Infection Research (DZIF)
- German Research Foundation (DFG) [SP483/4-1/2, SFB/TRR57]
Background & Aims: NK cells regulate liver fibrosis by killing activated hepatic stellate cells (HSCs) and are controlled themselves by immune cells and/or soluble factors. Here, we analysed if CD4(+) regulatory T cells (Tregs) modify the interaction between NK cells and HSCs. Methods: The modification of NK cell activity against HSCs was studied in CD56(high)CD16(-) NK cells, using a flow cytometric CD107a degranulation assay and co-cultures with Tregs from healthy donors and patients with hepatitis C, respectively. We studied the underlying mechanisms in detail, applying Treg supernatants, Treg pretreated HSCs, and recombinant IL-8, TGF-beta 1, and IL-10 as well as blocking experiments with neutralizing antibodies and analysed Treg-associated changes in the expression of NK cell receptor ligands on HSCs. Results: Tregs suppressed NK cell activation during HSC co-culture in a cell-contact-dependent manner involving the cytotoxic T-lymphocyte antigen 4 (CTLA-4). NK cell degranulation was further reduced, when HSCs had been pretreated with Tregs (p = 0.043), Treg supernatants (p = 0.001) or recombinant IL-8 (R = 0.630, p = 0.001) and TGF-beta 1 (R = 0.608, p = 0.002), respectively. This additional inhibitory effect corresponded to the IL-8/TGF-beta 1-mediated downregulation of MIC-A/B and HLA class-I on HSCs. Tregs from hepatitis C likewise inhibited NK cell activity, which was reversed significantly in specific blocking experiments. Conclusions: Our data indicate that Tregs interfere with NK cell regulation of fibrogenesis via both direct cell-contact-dependent inhibition of NK cells and release of soluble factors, downregulating activating NK cell receptor ligands on HSCs. Our data may be particularly relevant for the intrahepatic accumulation of Tregs in chronic hepatitis C because downregulated NK cell activity against HSCs may blunt their control of fibrogenesis. (C) 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据