Transcription Factor IRF4 Dysfunction Affects the Immunosuppressive Function of Treg Cells in Patients with Primary Immune Thrombocytopenia

Meiwen Tang; Luya Cheng; Feng Li; Boting Wu; Pu Chen; Yanxia Zhan; Fanli Hua; Zhihui Min; Yang Ke; Chanjuan Liu; Ling Yuan; Lihua Sun; Hao Chen; Lili Ji; Yunfeng Cheng

doi:10.1155/2019/1050285

Transcription Factor IRF4 Dysfunction Affects the Immunosuppressive Function of Treg Cells in Patients with Primary Immune Thrombocytopenia

Biomed Res Int. 2019 Jul 10:2019:1050285. doi: 10.1155/2019/1050285. eCollection 2019.

Authors

Meiwen Tang¹, Luya Cheng¹, Feng Li^{1

2}, Boting Wu³, Pu Chen⁴, Yanxia Zhan¹, Fanli Hua², Zhihui Min⁵, Yang Ke¹, Chanjuan Liu¹, Ling Yuan¹, Lihua Sun², Hao Chen⁶, Lili Ji¹, Yunfeng Cheng^{1

2

5

7}

Affiliations

¹ Department of Hematology, Zhongshan Hospital Fudan University, Shanghai 200032, China.
² Department of Hematology, Zhongshan Hospital Qinpu Branch, Fudan University, Shanghai 201700, China.
³ Department of Transfusion Medicine, Zhongshan Hospital Fudan University, Shanghai 200032, China.
⁴ Department of Clinical Laboratory, Zhongshan Hospital Fudan University, Shanghai 200032, China.
⁵ Institute of Clinical Science, Zhongshan Hospital Fudan University, Shanghai 200032, China.
⁶ Department of Thoracic Surgery, Zhongshan Hospital Xuhui Branch, Fudan University, Shanghai 200031, China.
⁷ Center for Tumor Diagnosis & Therapy, Jinshan Hospital, Fudan University, Shanghai 201508, China.

Abstract

Background: Th17/Treg balance skews towards Th17 in ITP patient. IRF4 has been highlighted for its close relationship to the immunosuppressive function of Treg cells and the IL-17 synthesis in CD4⁺ T cells. This study was aimed at examining the effects of IRF4 to the Th17/Treg cells in patients with ITP.

Methods: Treg and Teff cells were isolated from PBMCs of newly diagnosed ITP patients. The percentages of CD4⁺CD25^hiFoxp3⁺Treg cells and the CD3⁺CD4⁺IL-17⁺Th17 cells were detected by flow cytometry. After being cultured, the supernatants of Tregs were collected for IL-10 concentration test. The IRF4 levels of Tregs were measured. Teffs were cultured alone or with Tregs for 24 hours. Then the supernatants were collected for IL-17 concentration test. The binding intensity of IRF4 to the gene IL-10 in Treg cells was detected by ChIP-qPCR. Metabolic assays for Teffs and Tregs were performed with Agilent Seahorse XF96 Analyzer.

Results: The secretion of IL-10 by Tregs was decreased in ITP patients. The intensity of IRF4 binding to IL-10 DNA of Tregs in patients was higher than that of normal controls and Teffs in ITP patients. The expressions of IRF4 of Tregs in ITP patients were remarkably lower than that of healthy controls. The percentage of Th17 cells in healthy controls was significantly increased after IRF4 mRNA silencing. Abnormal metabolism of Treg and Teff cells was found in ITP patients.

Conclusion: The skewed ratio of Th17/Treg cells and dysfunction of Treg cells in newly diagnosed ITP patients was at least partly caused by IRF4 dysfunction. The underlying mechanism might be the impact of IRF4 on the metabolism of Treg and Teff cells.

MeSH terms

Adult
Aged
CD4-Positive T-Lymphocytes / immunology
Female
Gene Expression Regulation
Humans
Immunosuppression Therapy / methods
Interferon Regulatory Factors / genetics*
Interferon Regulatory Factors / immunology
Interleukin-10 / genetics*
Male
Middle Aged
Protein Binding / immunology
Purpura, Thrombocytopenic, Idiopathic / genetics*
Purpura, Thrombocytopenic, Idiopathic / immunology
Purpura, Thrombocytopenic, Idiopathic / pathology
T-Lymphocytes, Regulatory / immunology*
T-Lymphocytes, Regulatory / metabolism
Th17 Cells / immunology
Th17 Cells / metabolism

Substances

Interferon Regulatory Factors
interferon regulatory factor-4
Interleukin-10