Thy-1 dependent uptake of mesenchymal stem cell-derived extracellular vesicles blocks myofibroblastic differentiation

Abstract

Bone marrow-derived mesenchymal stem cells (MSC) have been promoted for multiple therapeutic applications. Many beneficial effects of MSCs are paracrine, dependent on extracellular vesicles (EVs). Although MSC-derived EVs (mEVs) are beneficial for acute lung injury and pulmonary fibrosis, mechanisms of mEV uptake by lung fibroblasts and their effects on myofibroblastic differentiation have not been established. We demonstrate that mEVs, but not fibroblast EVs (fEVs), suppress TGFβ1-induced myofibroblastic differentiation of normal and idiopathic pulmonary fibrosis (IPF) lung fibroblasts. MEVs display increased time- and dose-dependent cellular uptake compared to fEVs. Removal or blocking of Thy-1, or blocking Thy-1-beta integrin interactions, decreased mEV uptake and prevented suppression of myofibroblastic differentiation. MicroRNAs (miRs) 199a/b-3p, 21-5p, 630, 22-3p, 196a-5p, 199b-5p, 34a-5p and 148a-3p are selectively packaged in mEVs. In silico analyses indicated that IPF lung fibroblasts have increased expression of genes that are targets of mEV-enriched miRs. MiR-630 mimics blocked TGFβ1 induction of CDH2 in normal and IPF fibroblasts, and antagomiR-630 abrogated the effect of mEV on CDH2 expression. These data suggest that the interaction of Thy-1 with beta integrins mediates mEV uptake by lung fibroblasts, which blocks myofibroblastic differentiation, and that mEVs are enriched for miRs that target profibrotic genes up-regulated in IPF fibroblasts.

Dust induces lung fibrosis through dysregulated DNA methylation

“…It is involved in cell–cell–matrix interaction, and it regulates fibrosis, promotes cell migration and adhesion . In the process of fibrosis, Thy‐1 can inhibit fibroblast trans‐differentiation and inhibit fibrosis by correlating with TGF‐β, which is called “fibrosis inhibitory gene”. It has been reported that DNA methylation occurs in Thy‐1 during idiopathic pulmonary fibrosis .…”

“…54 In the process of fibrosis, Thy-1 can inhibit fibroblast trans-differentiation and inhibit FIGURE 4 Morphological, proliferative and fibrotic changes in RLE-6TN cells exposed to dust. Cells were exposed to 0, 25,50,100,150,200,300,400 fibrosis by correlating with TGF-β, 55 which is called "fibrosis inhibitory gene". It has been reported that DNA methylation occurs in Thy-1 during idiopathic pulmonary fibrosis.…”

Potential function and molecular mechanism of circRNAs involved in idiopathic pulmonary fibrosis

“…Several published studies have demonstrated that up-regulation of miR-486-5p and miR-630 contributes to IPF progression [45,46] and CADM1, OLFM4, PDGFRA as well as YAP1 genes play a crucial role in the pathogenesis of IPF [47][48][49][50].…”

Therapeutic Use of Extracellular Vesicles for Acute and Chronic Lung Disease

“…The amnion epithelium-derived EVs also had a direct effect on immune cells, including increased macrophage phagocytosis, reduced neutrophil myeloperoxidase, and suppressed T cell proliferation. Shentu and colleagues used human bone marrow MSC-derived EVs to suppress the transforming growth factor beta 1 (TGFβ1)-stimulated myofibroblast differentiation of normal and IPF lung fibroblasts [63]. They found that MSC-derived EVs utilized a Thy1-integrin dependent pathway for cell-to-cell communication for uptake into fibroblasts and the delivery of EV cargo and resulting anti-fibrotic activity.…”