title: Reduced plasma levels of Ang-2 and sEng as novel biomarkers in hereditary hemorrhagic telangiectasia (HHT).
abstract: BACKGROUND
  Hereditary hemorrhagic telangiectasia (HHT; OMIM 187300) is an autosomal dominant vascular disorder characterized by telangiectases and internal arteriovenous malformations caused by mutations in certain elements of the TGF-beta receptor complex. In the case of HHT1 mutations in the endoglin gene are responsible, whereas mutations in the ALK1 gene (an activin receptor-like kinase 1), lead to HHT2. Another two loci found at chromosome 5 and chromosome 7, whose target genes remain unidentified, lead to types 3 and 4 of the disease, respectively. Mutations in the MADH4/SMAD4 gene, another member of the TGF-beta signalling pathway, lead to a combined syndrome of familial juvenile polyposis associated with HHT.
  
  
  METHODS
  In an attempt to identify some soluble components differentially expressed in the plasma of HHT patients, angiopoietin-2 and soluble endoglin concentrations were analyzed with standard quantitative sandwich ELISA.
  
  
  RESULTS
  Angiopoietin-2 and soluble endoglin levels are reduced in plasma of HHT patients compared to control individuals, and a diagnostic algorithm for HHT based on these protein levels is proposed.
  
  
  CONCLUSIONS
  Down-regulated protein levels of angiopoietin-2 and soluble endoglin in plasma represent novel HHT biomarkers that could be useful in the biochemical diagnosis of HHT facilitating the rapid identification of potential HHT patients.
authors.affiliation: Centro de Investigación Biomédica en Red de Enfermedades Raras, Madrid, Spain.
authors.forename: Luisa
authors.initials: L
authors.lastname: Ojeda-Fernandez
authors.forename: Laura
authors.initials: L
authors.lastname: Barrios
authors.forename: Alicia
authors.initials: A
authors.lastname: Rodriguez-Barbero
authors.forename: Lucia
authors.initials: L
authors.lastname: Recio-Poveda
authors.forename: Carmelo
authors.initials: C
authors.lastname: Bernabeu
authors.forename: Luisa M
authors.initials: LM
authors.lastname: Botella
mesh_terms: D000328:Adult; D000368:Aged; D042702:Angiopoietin-2 / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D015703:Antigens, CD / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D016002:Discriminant Analysis; D000071063:Endoglin; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D011956:Receptors, Cell Surface / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D012995:Solubility; D013683:Telangiectasia, Hereditary Hemorrhagic / Q000097:blood* / Q000175:diagnosis / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000378:metabolism; D055815:Young Adult
chemical_list: D042702:Angiopoietin-2; D015703:Antigens, CD; D015415:Biomarkers; C064206:ENG protein, human; D000071063:Endoglin; D011956:Receptors, Cell Surface; D016212:Transforming Growth Factor beta