Mesenchymal Stem Cells Deliver Exogenous MicroRNA-let7c via Exosomes to Attenuate Renal Fibrosis

• Published in: Molecular therapy Vol. 24; no. 7; pp. 1290 - 1301
• Main Authors: Wang, Bo, Yao, Kevin, Huuskes, Brooke M, Shen, Hsin-Hui, Zhuang, Junli, Godson, Catherine, Brennan, Eoin P, Wilkinson-Berka, Jennifer L, Wise, Andrea F, Ricardo, Sharon D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2016; Elsevier Limited; Nature Publishing Group
• Subjects: Actins - metabolism; Animals; Biological Transport; Cell cycle; Cell division; Cell Engineering; Collagen; Collagen - metabolism; Developmental biology; Disease Models, Animal; Exosomes - metabolism; Extracellular Vesicles - metabolism; Fibrosis; Gene Expression; Gene Expression Regulation; Gene Transfer Techniques; Growth factors; Humans; Kidney diseases; Kidney Diseases - genetics; Kidney Diseases - metabolism; Kidney Diseases - pathology; Kidney Diseases - therapy; Male; Mesenchymal Stromal Cells - metabolism; Mice; MicroRNAs; MicroRNAs - genetics; Original; Proteins; Rats; Receptor, Epidermal Growth Factor - metabolism; Smooth muscle; Stem cells; Transduction, Genetic; Australia; Victoria Australia
• ISSN: 1525-0016; 1525-0024
• DOI: 10.1038/mt.2016.90

The advancement of microRNA (miRNA) therapies has been hampered by difficulties in delivering miRNA to the injured kidney in a robust and sustainable manner. Using bioluminescence imaging in mice with unilateral ureteral obstruction (UUO), we report that mesenchymal stem cells (MSCs), engineered to overexpress miRNA-let7c (miR-let7c-MSCs), selectively homed to damaged kidneys and upregulated miR-let7c gene expression, compared with nontargeting control (NTC)-MSCs. miR-let7c-MSC therapy attenuated kidney injury and significantly downregulated collagen IVα1, metalloproteinase-9, transforming growth factor (TGF)-β1, and TGF-β type 1 receptor (TGF-βR1) in UUO kidneys, compared with controls. In vitro analysis confirmed that the transfer of miR-let7c from miR-let7c-MSCs occurred via secreted exosomal uptake, visualized in NRK52E cells using cyc3-labeled pre-miRNA-transfected MSCs with/without the exosomal inhibitor, GW4869. The upregulated expression of fibrotic genes in NRK52E cells induced by TGF-β1 was repressed following the addition of isolated exosomes or indirect coculture of miR-let7c-MSCs, compared with NTC-MSCs. Furthermore, the cotransfection of NRK52E cells using the 3′UTR of TGF-βR1 confirmed that miR-let7c attenuates TGF-β1-driven TGF-βR1 gene expression. Taken together, the effective antifibrotic function of engineered MSCs is able to selectively transfer miR-let7c to damaged kidney cells and will pave the way for the use of MSCs for therapeutic delivery of miRNA targeted at kidney disease.