HIF-1α regulates IL-1β and IL-17 in sarcoidosis
Abstract
Sarcoidosis is a complex systemic granulomatous disease of unknown etiology characterized by the presence of activated macrophages and Th1/Th17 effector cells. Data mining of our RNA-Seq analysis of CD14+ monocytes showed enrichment for metabolic and hypoxia inducible factor (HIF) pathways in sarcoidosis. Further investigation revealed that sarcoidosis macrophages and monocytes exhibit higher protein levels for HIF-α isoforms, HIF-1β, and their transcriptional co-activator p300 as well as glucose transporter 1 (Glut1). In situ hybridization of sarcoidosis granulomatous lung tissues showed abundance of HIF-1α in the center of granulomas. The abundance of HIF isoforms was mechanistically linked to elevated IL-1β and IL-17 since targeted down regulation of HIF-1α via short interfering RNA or a HIF-1α inhibitor decreased their production. Pharmacological intervention using chloroquine, a lysosomal inhibitor, decreased lysosomal associated protein 2 (LAMP2) and HIF-1α levels and modified cytokine production. These data suggest that increased activity of HIF-α isoforms regulate Th1/Th17 mediated inflammation in sarcoidosis.
Data availability
All data generated or analysed during this study are included in the manuscript.
Article and author information
Author details
Funding
National Heart, Lung, and Blood Institute (R01HL113508)
- Lobelia Samavati
American Lung Association
- Lobelia Samavati
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Jos WM van der Meer, Radboud University Medical Centre, Netherlands
Ethics
Human subjects: The Committee for Investigations Involving Human Subjects at Wayne State University approved the protocol for obtaining alveolar macrophages by bronchoalveolar lavage (BAL) and blood by phlebotomy from control subjects and patients with sarcoidosis.The IRB number for this study is 055208MP4E. Informed consent was obtained from all subjects enrolled for the study.
Version history
- Received: December 19, 2018
- Accepted: April 3, 2019
- Accepted Manuscript published: April 4, 2019 (version 1)
- Accepted Manuscript updated: May 1, 2019 (version 2)
- Version of Record published: May 8, 2019 (version 3)
Copyright
© 2019, Talreja et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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