title: Scleroderma dermal microvascular endothelial cells exhibit defective response to pro-angiogenic chemokines.
abstract: OBJECTIVE
  Angiogenesis plays a critical role in SSc (scleroderma). The aim of this study was to examine the expression of growth-regulated protein-γ (Gro-γ/CXCL3), granulocyte chemotactic protein 2 (GCP-2/CXCL6) and their receptor CXCR2 in endothelial cells (ECs) isolated from SSc skin and determine whether these cells mount an angiogenic response towards pro-angiogenic chemokines. The downstream signalling pathways as well as the pro-angiogenic transcription factor inhibitor of DNA-binding protein 1 (Id-1) were also examined.
  
  
  METHODS
  Skin biopsies were obtained from patients with dcSSc. ECs were isolated via magnetic positive selection. Angiogenesis was measured by EC chemotaxis assay.
  
  
  RESULTS
  Gro-γ/CXCL3 and GCP-2/CXCL6 were minimally expressed in both skin types but elevated in SSc serum. Pro-angiogenic chemokine mRNA was greater in SSc ECs than in normal ECs. SSc ECs did not migrate to vascular endothelial growth factor (VEGF), Gro-γ/CXCL3, GCP-2/CXCL6 or CXCL16. The signalling pathways stimulated by these chemokines were also dysregulated. Id-1 mRNA in SSc ECs was lower compared with normal ECs, and overexpression of Id-1 in SSc ECs increased their ability to migrate towards VEGF and CXCL16.
  
  
  CONCLUSIONS
  Our results show that SSc ECs are unable to respond to pro-angiogenic chemokines despite their increased expression in serum and ECs. This might be due to the differences in the signalling pathways activated by these chemokines in normal vs SSc ECs. In addition, the lower expression of Id-1 also decreases the angiogenic response. The inability of pro-angiogenic chemokines to promote EC migration provides an additional mechanism for the impaired angiogenesis that characterizes SSc.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Scleroderma Program, ptsou@med.umich.edu.
authors.forename: Pei-Suen
authors.initials: PS
authors.lastname: Tsou
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Biology Department, Albion College, Albion, MI.
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Rabquer
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Ray A
authors.initials: RA
authors.lastname: Ohara
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: William A
authors.initials: WA
authors.lastname: Stinson
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Phillip L
authors.initials: PL
authors.lastname: Campbell
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: M Asif
authors.initials: MA
authors.lastname: Amin
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Beatrix
authors.initials: B
authors.lastname: Balogh
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: George
authors.initials: G
authors.lastname: Zakhem
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Renauer
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Ann
authors.initials: A
authors.lastname: Lozier
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
authors.forename: Eshwar
authors.initials: E
authors.lastname: Arasu
authors.affiliation: Department of Pathology, Yale University, New Haven, CT.
authors.forename: G Kenneth
authors.initials: GK
authors.lastname: Haines
authors.affiliation: Department of Medicine, University of Toledo Medical Center, Toledo, OH and.
authors.forename: Bashar
authors.initials: B
authors.lastname: Kahaleh
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Scleroderma Program.
authors.forename: Elena
authors.initials: E
authors.lastname: Schiopu
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Scleroderma Program.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Khanna
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, VA Medical Service, Ann Arbor, MI, USA.
authors.forename: Alisa E
authors.initials: AE
authors.lastname: Koch
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000494:pharmacology; D016022:Case-Control Studies; D002478:Cells, Cultured; D018925:Chemokines / Q000096:biosynthesis / Q000494:pharmacology / Q000502:physiology*; D002633:Chemotaxis / Q000187:drug effects / Q000502:physiology; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D051798:Inhibitor of Differentiation Protein 1 / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology*; D023063:Receptors, Interleukin-8B / Q000378:metabolism; D012595:Scleroderma, Systemic / Q000378:metabolism / Q000473:pathology*; D015398:Signal Transduction / Q000502:physiology; D012867:Skin / Q000098:blood supply*; D013755:Tetradecanoylphorbol Acetate / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D043925:Angiogenesis Inducing Agents; D018925:Chemokines; C497453:ID1 protein, human; D051798:Inhibitor of Differentiation Protein 1; D023063:Receptors, Interleukin-8B; C016658:phorbolol myristate acetate; D013755:Tetradecanoylphorbol Acetate
keywords: angiogenesis; chemokines; scleroderma