Exosomes from human umbilical cord mesenchymal stem cells attenuate the inflammation of severe steroid-resistant asthma by reshaping macrophage polarization

Abstract

Background Severe, steroid-resistant asthma (SSRA) is a serious clinical problem in asthma management. Affected patients have severe clinical symptoms, worsened quality of life, and do not respond to steroid, a mainstay steroid treatment of asthma. Thus, effective therapies are urgently needed. Exosomes derived from mesenchymal stem cell (MSC-Exo) has become attractive candidates for the lung inflammatory diseases through its immunomodulatory effects. In this study, we explored the therapeutic effects of MSC-Exo in SSRA and identified the therapeutic mechanism of MSC-Exo. Method Exosomes from human umbilical cord mesenchymal stem cell (hUCMSC) were isolated and characterized by transmission electron microscopy, nanoparticle tracking analysis and flow cytometry analysis. Effects of MSC-Exo on airway hyper responsiveness (AHR), inflammation, histopathology, and macrophage polarization in SSRA in mice were evaluated. Systematic depletion of macrophages determined the role of macrophages in the therapeutic effect of SSRA in mice. LPS-stimulated RAW 264.7 cell model was constructed to determine the underlying mechanism of MSC-Exo on macrophage polarization. qRT-PCR, Western blotting, immunofluorescence, and flow cytometry were performed to evaluate the expression of M1 or M2 markers. Tandem mass tags (TMT)-labeled quantitative proteomics were applied to explore the central protein during the regulation effect of MSC-Exo on macrophage polarization. Knockdown and overexpression of TRAF1 were used to further clarify the role of the central protein on macrophage polarization. Result We successfully isolated and characterized exosomes from hUCMSCs. We verified that the intratracheal administration of MSC-Exo reversed AHR, histopathology changes, and inflammation in SSRA mice. Systematic depletion of macrophages weakened the therapeutic effect of MSC-Exo. We found that MSC-Exo treatment inhibited M1 polarization and promoted M2 polarization in LPS-stimulated RAW 264.7 cells. Subsequently, tumor necrosis factor receptor-associated factor 1 (TRAF1) was determined as the central protein which may be closely related to the regulation of macrophage polarization from TMT-labeled quantitative proteomics analysis. Knockdown and overexpression of TRAF1 demonstrated that the effect of MSC-Exo treatment on macrophage polarization, NF-κB and PI3K/AKT signaling was dependent on TRAF1. Conclusion MSC-Exo can ameliorate SSRA by moderating inflammation, which is achieved by reshaping macrophage polarization via inhibition of TRAF1.

Emerging Therapeutic Potential of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Chronic Respiratory Diseases: An Overview of Recent Progress

“…The therapeutic role of MSC-EVs in asthma has been investigated both in vitro and in vivo. Dong et al (Dong et al, 2021) found that human UC-MSCs derived EVs inhibited inflammation by reshaping macrophage polarization via blocking tumor necrosis factor receptor associated factor 1 (TRAF1). Fang et al (Fang et al, 2020a) also investigated effects of MSC-EVs on macrophages in asthma disease model, and their research suggested that EVs from human iPSC-MSCs inhibited the recruitment and polarization of lung macrophages in mice with allergic airway inflammation.…”

Mesenchymal Stem Cell Immunomodulation: A Novel Intervention Mechanism in Cardiovascular Disease

“…In the steroid-resistant mouse model, Bing Dong and his colleagues found that intratracheal administration of exosomes treatment reduced inflammation and reduced M1 macrophages, and promoted M2 macrophages. This effect could achieve by inhibiting the TNF receptor-associated factor 1 (TRAF1) ( Dong et al, 2021 ). In this way, MSCs promote the polarization of macrophages from a pro-inflammatory M1 phenotype to an anti-inflammatory M2 phenotype and regulate through related proteins, exosomes, and inflammatory factors.…”

Microrna-342-3p Loaded by Human Umbilical Cord Mesenchymal Stem Cells-derived Exosomes Attenuates Deep Vein Thrombosis by Downregulating EDNRA

“…HucMSCs were placed in osteogenic medium (0.1 mM dexamethasone, 10 mM β-glycerophosphate and 50 mM ascorbyl phosphate) or adipogenic medium (Cyagen Biosciences, CA, USA). Two weeks later, the osteogenic and adipogenic differentiation potentials were evaluated by Alizarin Red and Oil Red O staining [16,17].…”