title: Angiogenic gene expression and vascular density are reflected in ultrasonographic features of synovitis in early Rheumatoid Arthritis: an observational study.
abstract: BACKGROUND
  Neovascularization contributes to the development of sustained synovial inflammation in the early stages of Rheumatoid Arthritis. Ultrasound (US) provides an indirect method of assessing synovial blood flow and has been shown to correlate with clinical disease activity in patients with Rheumatoid Arthritis. This study examines the relationship of US determined synovitis with synovial vascularity, angiogenic/lymphangiogenic factors and cellular mediators of inflammation in a cohort of patients with early Rheumatoid Arthritis (RA) patients prior to therapeutic intervention with disease modifying therapy or corticosteroids.
  
  
  METHODS
  An ultrasound guided synovial biopsy of the supra-patella pouch was performed in 12 patients with early RA prior to treatment. Clinical, US and biochemical assessments were undertaken prior to the procedure. Ultrasound images and histological samples were obtained from the supra-patella pouch. Histological samples were stained for Factor VIII and a-SMA (a-smooth muscle actin). Using digital imaging analysis a vascular area score was recorded. QT-PCR (quantitative-PCR) of samples provided quantification of angiogenic and lymphangiogenic gene expression and immunohistochemistry stained tissue was scored for macrophage, T cell and B cell infiltration using an existing semi-quantitative score.
  
  
  RESULTS
  Power Doppler showed a good correlation with histological vascular area (Spearman r--0.73) and angiogenic factors such as vascular endothelial growth factor-A (VEGF-A), Angiopoietin 2 and Tie-2. In addition, lymphangiogenic factors such as VEGF-C and VEGF-R3 correlated well with US assessment of synovitis. A significant correlation was also found between power Doppler and synovial thickness, pro-inflammatory cytokines and sub-lining macrophage infiltrate. Within the supra-patella pouch there was no significant difference in US findings, gene expression or inflammatory cell infiltrate between any regions of synovium biopsied.
  
  
  CONCLUSIONS
  Ultrasound assessment of synovial tissue faithfully reflects synovial vascularity. Both grey scale and power Doppler synovitis in early RA patients correlate with a pro-angiogenic and lymphangiogenic gene expression profile. In early RA both grey scale and power Doppler synovitis are associated with a pro-inflammatory cellular and cytokine profile providing considerable validity in its use as an objective assessment of synovial inflammation in clinical practice.
authors.affiliation: Rheumatology Department, Barts Health NHS trust Mile End hospital, London, EH1 4DG, UK. stephenkelly@bartshealth.nhs.uk.
authors.forename: Stephen
authors.initials: S
authors.lastname: Kelly
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. m.bombardieri@qmul.ac.uk.
authors.forename: Michele
authors.initials: M
authors.lastname: Bombardieri
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. f.humby@qmul.ac.uk.
authors.forename: Frances
authors.initials: F
authors.lastname: Humby
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. norang@doctors.org.uk.
authors.forename: Nora
authors.initials: N
authors.lastname: Ng
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. alessandramarrelli@tiscali.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Marrelli
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. s.riahi@qmul.ac.uk.
authors.forename: Sudeh
authors.initials: S
authors.lastname: Riahi
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. m.dicicco@qmul.ac.uk.
authors.forename: Maria
authors.initials: M
authors.lastname: DiCicco
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. a.mahto@qmul.ac.uk.
authors.forename: Arti
authors.initials: A
authors.lastname: Mahto
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. lu.zou@qmul.ac.uk.
authors.forename: Lu
authors.initials: L
authors.lastname: Zou
authors.affiliation: Rheumatology Department, Barts Health NHS trust Mile End hospital, London, EH1 4DG, UK. Dev.pyne@bartshealth.nhs.uk.
authors.forename: Debasish
authors.initials: D
authors.lastname: Pyne
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. r.e.hands@qmul.ac.uk.
authors.forename: Rebecca E
authors.initials: RE
authors.lastname: Hands
authors.affiliation: Queen Mary University of London, Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Charterhouse Square, London, EC1M 6BQ, UK. c.pitzalis@qmul.ac.uk.
authors.forename: Costantino
authors.initials: C
authors.lastname: Pitzalis
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging* / Q000235:genetics; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000235:genetics; D013583:Synovial Membrane / Q000098:blood supply / Q000000981:diagnostic imaging*; D013585:Synovitis / Q000000981:diagnostic imaging* / Q000235:genetics; D014463:Ultrasonography