title: Preliminary evidence of sustained expression of angiopoietin-2 during monocyte differentiation in chronic hepatitis C.
abstract: BACKGROUND
  Monocytes are essential precursors of antigen-presenting cells, such as macrophages and dendritic cells, and contribute to the pathogenesis of chronic inflammatory diseases and cancer.
  
  
  OBJECTIVE
  As Tie2-expressing monocytes (TEMs) are increased in the peripheral blood of patients with chronic hepatitis C (CHC), we aimed to examine the expression of Tie2 and angiopoietins (Ang1 and Ang2) during monocyte differentiation and maturation in CHC.
  
  
  METHODS
  The expression of Tie2, CD11b, CD80, CD83, CD86 and MHC-II was measured by flow cytometry in peripheral blood monocytes and monocytes-derived cells (Mo-DCs) from nine healthy subjects and eight CHC patients whose HCV infection was unresolved after combination therapy. Ang1 and Ang2 levels were measured in cellular supernatants by ELISA.
  
  
  RESULTS
  Mo-DCs from CHC patients expressed differential patterns of maturation markers compared with controls--primarily with regard to CD80. Tie2 was downregulated during monocyte differentiation in controls and CHC patients, whereas Ang1 expression was constant. However, Ang2 levels fell significantly during the differentiation of control monocytes, in contrast with those from CHC patients in whom Ang2 expression remained stable throughout differentiation.
  
  
  CONCLUSIONS
  Altered expression of the Ang/Tie2 system in monocytes and Mo-DCs from CHC patients might account for the inflammatory and angiogenic disorders that are related to CHC. An increased understanding of Ang/Tie2 system regulation might be helpful in designing strategies to prevent CHC progression.
authors: Liver Unit, Hospital Universitario de La Princesa & Instituto de Investigación Sanitaria Princesa, Universidad Autónoma de Madrid & Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Madrid, Spain.
authors: Yolanda
authors: Y
authors: Rodríguez-Muñoz
authors: Samuel
authors: S
authors: Martín-Vílchez
authors: Rosario
authors: R
authors: López-Rodríguez
authors: Ángel
authors: Á
authors: Hernández-Bartolomé
authors: Luisa
authors: L
authors: García-Buey
authors: María J
authors: MJ
authors: Borque
authors: Ricardo
authors: R
authors: Moreno-Otero
authors: Paloma
authors: P
authors: Sanz-Cameno
mesh_terms: D000328:Adult; D000368:Aged; D042683:Angiopoietin-1 / Q000378:metabolism; D042702:Angiopoietin-2 / Q000378:metabolism*; D000998:Antiviral Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D002454:Cell Differentiation; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism* / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism* / Q000821:virology; D042787:Receptor, TIE-2 / Q000378:metabolism
chemical_list: C467630:ANGPT1 protein, human; D042683:Angiopoietin-1; D042702:Angiopoietin-2; D000998:Antiviral Agents; D015415:Biomarkers; D042787:Receptor, TIE-2