title: Enrichment of Scleroderma Vascular Disease-Associated Autoantigens in Endothelial Lineage Cells.
abstract: Scleroderma patients with autoantibodies to CENPs and/or interferon-inducible protein 16 (IFI-16) are at increased risk of severe vascular complications. This study was undertaken to determine whether these autoantigens are enriched in cells of the vasculature.
  
  
  
  Successive stages of embryoid bodies (EBs) as well as vascular progenitors were used to evaluate the expression of scleroderma autoantigens IFI-16 and CENP by immunoblotting. CD31 was included to mark early blood vessels. IFI-16 and CD31 expression were defined in paraffin-embedded skin sections from scleroderma patients and from healthy controls. IFI-16 expression was determined by flow cytometric analysis in circulating endothelial cells (CECs) and circulating hematopoietic progenitor cells.
  
  
  
  Expression of CENP-A, IFI-16, and CD31 was enriched in EBs on days 10 and 12 of differentiation, and particularly in cultures enriched in vascular progenitors (IFI-16, CD31, and CENPs A and B). This pattern was distinct from that of comparator autoantigens. Immunohistochemical staining of paraffin-embedded skin sections showed enrichment of IFI-16 in CD31-positive vascular endothelial cells in biopsy specimens from scleroderma patients and normal controls. Flow cytometric analysis revealed IFI-16 expression in circulating hematopoietic progenitor cells but minimal expression in CECs.
  
  
  
  Our findings indicate that expression of the scleroderma autoantigens IFI-16 and CENPs, which are associated with severe vascular disease, is increased in vascular progenitors and mature endothelial cells. High level, lineage-enriched expression of autoantigens may explain the striking association between clinical phenotypes and the immune targeting of specific autoantigens.
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Zsuzsanna H
authors.initials: ZH
authors.lastname: McMahan
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Tricia R
authors.initials: TR
authors.lastname: Cottrell
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Fredrick M
authors.initials: FM
authors.lastname: Wigley
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Brendan
authors.initials: B
authors.lastname: Antiochos
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Elias T
authors.initials: ET
authors.lastname: Zambidis
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Tea Soon
authors.initials: TS
authors.lastname: Park
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Marc K
authors.initials: MK
authors.lastname: Halushka
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Laura
authors.initials: L
authors.lastname: Gutierrez-Alamillo
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Raffaello
authors.initials: R
authors.lastname: Cimbro
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Antony
authors.initials: A
authors.lastname: Rosen
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland. lcr@jhmi.edu.
authors.forename: Livia
authors.initials: L
authors.lastname: Casciola-Rosen
mesh_terms: D001324:Autoantigens / Q000276:immunology* / Q000378:metabolism; D016022:Case-Control Studies; D019070:Cell Lineage; D000076247:Centromere Protein A; D051936:Centromere Protein B / Q000276:immunology* / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000276:immunology* / Q000378:metabolism; D058732:Embryoid Bodies / Q000276:immunology* / Q000378:metabolism; D042783:Endothelial Cells / Q000276:immunology* / Q000378:metabolism; D066026:Endothelial Progenitor Cells / Q000276:immunology* / Q000378:metabolism; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D007963:Leukocytes, Mononuclear; D009687:Nuclear Proteins / Q000276:immunology* / Q000378:metabolism; D010750:Phosphoproteins / Q000276:immunology* / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D045743:Scleroderma, Diffuse / Q000276:immunology / Q000378:metabolism; D045745:Scleroderma, Limited / Q000276:immunology / Q000378:metabolism; D012595:Scleroderma, Systemic / Q000276:immunology* / Q000378:metabolism; D012867:Skin / Q000276:immunology / Q000378:metabolism
chemical_list: D001324:Autoantigens; C000619700:CENPA protein, human; C497926:CENPB protein, human; D000076247:Centromere Protein A; D051936:Centromere Protein B; D002868:Chromosomal Proteins, Non-Histone; D009687:Nuclear Proteins; D010750:Phosphoproteins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; C076700:IFI16 protein, human