title: Exosomes isolated from serum of systemic sclerosis patients display alterations in their content of profibrotic and antifibrotic microRNA and induce a profibrotic phenotype in cultured normal dermal fibroblasts.
abstract: OBJECTIVE
  Exosomes are lipid bilayer-bound microvesicles containing various macromolecules including numerous microRNA (miRNA). Exosomes mediate intercellular communication by fusing and releasing their macromolecular content into target cells. Here, we analysed the content of profibrotic and antifibrotic miRNAs in exosomes isolated from the serum of systemic sclerosis (SSc) patients and tested their ability to induce a profibrotic phenotype in normal human dermal fibroblasts in vitro.
  
  
  METHODS
  Exosomes were isolated from serum from patients with limited cutaneous or diffuse cutaneous SSc and were characterised by Nanosight Particle Tracking Analysis, exosome antibody arrays, and transmission electron microscopy. The content of nine profibrotic and eighteen antifibrotic miRNA was assessed in the isolated exosomes by semiquantitative real time PCR. The effects of the isolated exosomes on cultured normal human dermal fibroblasts were assessed by real time PCR and Western blotting.
  
  
  RESULTS
  The isolated serum exosomes displayed the expected exosome size and morphology and contained characteristic exosome proteins. Six profibrotic miRNAs were increased and ten antifibrotic miRNAs were decreased in SSc serum exosomes compared to normal serum exosomes. The levels of eight miRNA were significantly different between exosomes from limited and diffuse SSc. Exosomes isolated from both limited or diffuse SSc patients caused dose-dependent stimulation of profibrotic gene expression and type I collagen and fibronectin production and secretion in normal human dermal fibroblasts in vitro.
  
  
  CONCLUSIONS
  Serum exosomes from SSc patients contain miRNA displaying a markedly profibrotic profile and induce a profibrotic phenotype in target normal fibroblasts in vitro suggesting a plausible mechanism for the extension of the fibrotic SSc process to non-affected tissues.
authors.affiliation: The Scleroderma Center and The Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Wermuth
authors.affiliation: The Scleroderma Center and The Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Sonsoles
authors.initials: S
authors.lastname: Piera-Velazquez
authors.affiliation: The Scleroderma Center and The Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA. sergio.jimenez@jefferson.edu.
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Jimenez
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics; D055354:Exosomes / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005353:Fibronectins / Q000096:biosynthesis; D005355:Fibrosis; D006801:Humans; D035683:MicroRNAs / Q000032:analysis*; D008875:Middle Aged; D010641:Phenotype; D012595:Scleroderma, Systemic / Q000097:blood / Q000473:pathology*; D012867:Skin / Q000166:cytology / Q000378:metabolism
chemical_list: D024042:Collagen Type I; D005353:Fibronectins; D035683:MicroRNAs