Heparan sulfate-dependent RAGE oligomerization is indispensable for pathophysiological functions of RAGE
- University at Buffalo, State University of New York, United States
- University of Colorado Anschutz Medical Campus, United States
- China Medical University, China
Abstract
RAGE, a druggable inflammatory receptor, is known to function as an oligomer but the exact oligomerization mechanism remains poorly understood. Previously we have shown that heparan sulfate (HS) plays an active role in RAGE oligomerization. To understand the physiological significance of HS-induced RAGE oligomerization in vivo, we generated RAGE knock-in mice (AgerAHA/AHA) by introducing point mutations to specifically disrupt HS-RAGE interaction. The RAGE mutant demonstrated normal ligand-binding but impaired capacity of HS-binding and oligomerization. Remarkably, AgerAHA/AHA mice phenocopied Ager-/- mice in two different pathophysiological processes, namely bone remodeling and neutrophil-mediated liver injury, which demonstrates that HS-induced RAGE oligomerization is essential for RAGE signaling. Our findings suggest that it should be possible to block RAGE signaling by inhibiting HS-RAGE interaction. To test this, we generated a monoclonal antibody that targets the HS-binding site of RAGE. This antibody blocks RAGE signaling in vitro and in vivo, recapitulating the phenotype of AgerAHA/AHA mice. By inhibiting HS-RAGE interaction genetically and pharmacologically, our work validated an alternative strategy to antagonize RAGE. Finally, we have performed RNA-seq analysis of neutrophils and lungs and found that while Ager -/- mice had a broad alteration of transcriptome in both tissues compared to wild-type mice, the changes of transcriptome in AgerAHA/AHA mice were much more restricted. This unexpected finding suggests that by preserving the expression of RAGE protein (in a dominant-negative form), AgerAHA/AHA mouse might represent a cleaner genetic model to study physiological roles of RAGE in vivo compared to Ager -/- mice.
Data availability
PMN and lung RNA-sequencing data have been deposited into the NCBI Gene Expression Omnibus database (accession number GSE174178). All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all the main Figures 1-7, Figure S1, S2, S3, S5 and S7.
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mRNA-seq analysis of RAGE knock-in (RageAHA/AHA) and RAGE-/- miceNCBI Gene Expression Omnibus, GSE174178.
Article and author information
Author details
Funding
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR07017)
- Ding Xu
National Heart, Lung, and Blood Institute (R01HL094463)
- Ding Xu
Buffalo Accelerator Funds
- Ding Xu
National Institute of General Medical Sciences (R01GM125095)
- Eric P Schmidt
National Institute of General Medical Sciences (R01GM114179)
- Dhaval K Shah
National Institute of Allergy and Infectious Diseases (R21AI138195)
- Dhaval K Shah
National Cancer Institute (R01CA246785)
- Dhaval K Shah
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal works in this study have been approved by the institutional animal care and use committee of the University at Buffalo (protocol number: ORB14126N and ORB18018).
Copyright
© 2022, Li 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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Heparan sulfate-dependent RAGE oligomerization is indispensable for pathophysiological functions of RAGE
eLife 11:e71403.
https://doi.org/10.7554/eLife.71403
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