title: Increased expression of M-CSF and IL-13 in vitreous of patients with proliferative diabetic retinopathy: implications for M2 macrophage-involving fibrovascular membrane formation.
abstract: OBJECTIVE
  We recently demonstrated that M2 macrophages were involved in the development of fibrovascular membranes (FVM) associated with proliferative diabetic retinopathy (PDR) possibly through the induction of periostin. The purpose of this study was to determine whether macrophage colony-stimulating factor (M-CSF) and interleukin (IL)-13, inducers of the M2 polarisation of macrophages from monocytes, are elevated in the vitreous of patients with PDR, and whether M2-polarised macrophages induce periostin production.
  
  
  METHODS
  We measured the levels of M-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-4, IL-13, soluble (s)CD163, periostin and vascular endothelial growth factor by sandwich ELISA in vitreous samples collected from 61 eyes of 47 patients with PDR, and 39 eyes of 36 patients with non-diabetic ocular diseases (control group). Human monocytes were polarised in vitro with GM-CSF, interferon-γ, and lipopolysaccharide for M1 macrophages, and M-CSF, IL-4, and IL-13 for M2 macrophages. Quantitative real-time PCR was used to determine the mRNA level of periostin.
  
  
  RESULTS
  The concentrations of M-CSF and IL-13 in the vitreous were significantly higher in patients with PDR than in non-diabetic controls (p<0.0001). There was a strong positive correlation between the vitreous concentrations of M-CSF and sCD163 and periostin. The mean vitreous level of IL-13 was significantly higher in eyes with FVMs than in those without FVMs (epicentre only). In vitro studies showed that M2-polarlised macrophages significantly increased the expression of the mRNA of periostin.
  
  
  CONCLUSIONS
  These findings indicate that the M2 polarisation of macrophages is induced by M-CSF and IL-13 in diabetic retinas. The presence of M-CSF and IL-13 would then promote FVM formation by periostin production.
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Nakama
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yedi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Ishikawa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Arita
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Nakao
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Miyazaki
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sassa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Oshima
authors.affiliation: Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School, Saga, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Izuhara
authors.affiliation: Department of Ophthalmology, Fukuoka University Chikushi Hospital, Fukuoka, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kono
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Ishibashi
mesh_terms: D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000235:genetics; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000601:surgery; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D018793:Interleukin-13 / Q000378:metabolism*; D016173:Macrophage Colony-Stimulating Factor / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D011956:Receptors, Cell Surface / Q000378:metabolism; D015861:Retinal Neovascularization / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014821:Vitrectomy; D018630:Vitreoretinopathy, Proliferative / Q000378:metabolism*; D014822:Vitreous Body / Q000378:metabolism*; D000098902:CD163 Antigen
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D000098902:CD163 Antigen; D015815:Cell Adhesion Molecules; C578095:IL13 protein, human; D018793:Interleukin-13; C512835:POSTN protein, human; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D016173:Macrophage Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor
keywords: Retina; Vitreous