Related Experiment Video
Updated: Oct 26, 2025
08:50
Depletion and Reconstitution of Macrophages in Mice
Published on: August 1, 2012
40.0K
Extracellular vesicles derived from DFO-preconditioned canine AT-MSCs reprogram macrophages into M2 phase.
Su-Min Park1, Ju-Hyun An1, Jeong-Hwa Lee1
1Department of Clinical Veterinary Science, Laboratory of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
Plos One
|July 26, 2021
Summary
Deferoxamine preconditioning enhances mesenchymal stem cell extracellular vesicles (EVs) with COX-2. These EVs reprogram macrophages to an anti-inflammatory M2 state by activating STAT3 signaling, offering a novel therapeutic approach.
Area of Science:
- Cell Biology
- Immunology
- Biotechnology
Background:
- Mesenchymal stem/stromal cells (MSCs) secrete anti-inflammatory factors via paracrine effects, with extracellular vesicles (EVs) being key mediators.
- Preconditioning MSCs using hypoxia or hypoxia-mimetic agents aims to enhance their therapeutic properties.
- Investigating molecular changes in preconditioned MSC-derived EVs is crucial for understanding their therapeutic potential.
Purpose of the Study:
- To investigate the increase of hypoxia-inducible factor 1-alpha (HIF-1α) and cyclooxygenase-2 (COX-2) in deferoxamine (DFO)-preconditioned canine MSCs (MSCDFO).
- To determine if these molecular changes in MSCDFO are reflected in their derived EVs (EVDFO).
- To evaluate the effect of EVDFO on macrophage polarization via EV transfer function.
Main Methods:
- MSCs were preconditioned with DFO, and molecular changes (HIF-1α, COX-2) were assessed.
- EVs derived from DFO-preconditioned MSCs (EVDFO) were isolated and characterized for COX-2 enrichment.
- Canine macrophage cell line (DH82) stimulated with lipopolysaccharide (LPS) was treated with EVDFO.
- Macrophage polarization was analyzed using quantitative real-time PCR and immunofluorescence for M1/M2 markers and STAT3 phosphorylation.
Main Results:
- DFO preconditioning increased HIF-1α accumulation and activated COX-2 production in MSCDFO.
- EVDFO were enriched with COX-2 protein.
- Treatment of LPS-induced DH82 with EVDFO increased signal transducer and transcription3 (STAT3) phosphorylation.
- EVDFO treatment reduced M1 marker expression and enhanced M2 surface markers in LPS-induced macrophages.
Conclusions:
- DFO preconditioning activates the HIF-1α/COX-2 signaling pathway in MSCs.
- Transfer of COX-2 via EVDFO effectively reprograms macrophages to an M2 phenotype.
- This reprogramming is mediated by promoting STAT3 phosphorylation, highlighting a novel mechanism for EV-based immunomodulation.
