Increased miR-142-3p Expression Might Explain Reduced Regulatory T Cell Function in Granulomatosis With Polyangiitis

Gerjan J Dekkema; Theo Bijma; Pytrick G Jellema; Anke Van Den Berg; Bart-Jan Kroesen; Coen A Stegeman; Peter Heeringa; Wayel H Abdulahad; Jan-Stephan Sanders

doi:10.3389/fimmu.2019.02170

Increased miR-142-3p Expression Might Explain Reduced Regulatory T Cell Function in Granulomatosis With Polyangiitis

Front Immunol. 2019 Sep 12:10:2170. doi: 10.3389/fimmu.2019.02170. eCollection 2019.

Authors

Affiliations

¹ Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
² Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, Groningen, Netherlands.
³ Medical Immunology Laboratory, Department of Laboratory Medicine, University Medical Center Groningen, Groningen, Netherlands.
⁴ Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.

Abstract

Objectives: Regulatory T cells (Tregs) are frequently functionally impaired in patients with granulomatosis with polyangiitis (GPA). However, the mechanism underlying their impaired function is unknown. Here, we hypothesized that Treg dysfunction in GPA is due to altered microRNA (miRNA) expression. Methods: RNA isolated from FACS-sorted memory (_M) Tregs (CD4⁺CD45RO⁺CD25⁺CD127^-) of 8 healthy controls (HCs) and 8 GPA patients without treatment was subjected to miRNA microarray analysis. Five differentially expressed miRNAs were validated in a larger cohort by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). An miRNA target gene database search revealed targets that were tested with RT-qPCR in _MTregs from patients and HCs. cAMP levels were measured using flow cytometry. Results: Microarray analysis revealed 19 differentially expressed miRNAs, of which miR-142-3p was confirmed to be significantly upregulated in _MTregs from GPA patients compared to those from HCs (1.9-fold, p = 0.03). In vitro overexpression of miR-142-3p lowered the suppressive capacity of _MTregs (2.1-fold, p = 0.03), and miR-142-3p expression correlated negatively with the suppressive capacity (rho = -0.446, p = 0.04). Overexpression of miR-142-3p significantly decreased cAMP levels (p = 0.02) and tended to decrease the mRNA levels of a predicted target gene, adenylate cyclase 9 (ADCY9; p = 0.06). In comparison to those from HCs, _MTregs from GPA patients had lower ADCY9 mRNA levels (2-fold, p = 0.008) and produced significantly less cAMP after stimulation. Importantly, induction of cAMP production in miR-142-3p overexpressed _MTregs by forskolin restored their suppressive function in vitro. Conclusion: Overexpression of miR-142-3p in _MTregs from GPA patients might cause functional impairment by targeting ADCY9, which leads to the suppression of cAMP production.

Keywords: ANCA—associated vasculitis; Treg—regulatory T cell; auto immune; microRNA; suppressive function.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adenylyl Cyclases / genetics
Cyclic AMP / immunology
Female
Granulomatosis with Polyangiitis / immunology*
Humans
Male
MicroRNAs / immunology*
Middle Aged
T-Lymphocytes, Regulatory / immunology*

Substances

MIRN142 microRNA, human
MicroRNAs
Cyclic AMP
Adenylyl Cyclases
adenylate cyclase 9