title: Altered expression of CD63 and exosomes in scleroderma dermal fibroblasts.
abstract: BACKGROUND
  Exosomes are small vesicles shed from various cells. They contain proteins, lipids, and nucleic acids, and are regarded as a tool of cell-cell communication.
  
  
  OBJECTIVE
  To reveal the putative role of exosomes in systemic sclerosis (SSc), and to elucidate the effect of exosomes on wound healing.
  
  
  METHODS
  The expression of common markers for exosomes (CD63, CD9, and CD81) and type I collagen were examined with real-time PCR, immunohistochemical analysis, ELISA, immunoblotting, and flow cytometry. The effect of serum-derived exosomes on wound healing was tested on full-thickness wounds in the mid-dorsal skin of BALB/c mice.
  
  
  RESULTS
  The expression levels of CD63 as well as CD9 and CD81 tended to be increased in SSc dermal fibroblasts compared to normal fibroblasts. Increased exosomes in a cultured media of SSc fibroblasts stimulated the expression levels of type I collagen in normal fibroblasts. As the mechanism, collagen-related microRNA levels in SSc fibroblast-derived exosomes were dysregulated, indicating that both the amount and the content of exosomes were altered in SSc. On the other hand, SSc sera showed significantly decreased exosome levels compared to normal sera. The frequencies of vascular involvements, including skin ulcers or pitting scars, were significantly increased in patients with decreased serum exosome levels. The healing of mice wounds was accelerated by treatment with serum-derived exosomes.
  
  
  CONCLUSIONS
  Vascular abnormalities in SSc may account for the decreased serum exosome levels by the disturbed transfer of exosomes from the skin tissue to the blood stream. Our study suggests the possibility that SSc patients with vascular involvements have decreased serum exosome levels, which causes the delay of wound healing due to down-regulation of collagen, resulting in higher susceptibility to pitting scars and/or ulcers. Exosome research will lead to a detailed understanding of SSc pathogenesis and new therapeutic approaches.
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Kayo
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan. Electronic address: mjin@kumamoto-u.ac.jp.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Jinnin
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Harada
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Kudo
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Wakana
authors.initials: W
authors.lastname: Nakayama
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Kuniko
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Ogata
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Ikko
authors.initials: I
authors.lastname: Kajihara
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukushima
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ihn
mesh_terms: D000818:Animals; D001706:Biopsy; D002450:Cell Communication; D024042:Collagen Type I / Q000737:chemistry; D003470:Culture Media; D055354:Exosomes / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008055:Lipids / Q000737:chemistry; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000378:metabolism; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction; D012595:Scleroderma, Systemic / Q000378:metabolism*; D012867:Skin / Q000378:metabolism*; D012883:Skin Ulcer / Q000378:metabolism; D060225:Tetraspanin 28 / Q000378:metabolism; D060245:Tetraspanin 29 / Q000378:metabolism; D060149:Tetraspanin 30 / Q000378:metabolism*
chemical_list: C554586:CD63 protein, human; C554798:CD81 protein, human; C554869:CD9 protein, human; C554587:Cd63 protein, mouse; C554799:Cd81 protein, mouse; C554870:Cd9 protein, mouse; D024042:Collagen Type I; D003470:Culture Media; D008055:Lipids; D035683:MicroRNAs; D060225:Tetraspanin 28; D060245:Tetraspanin 29; D060149:Tetraspanin 30
keywords: CD63; Exosomes; Systemic sclerosis