title: Use of immunohistologic and in situ hybridization techniques in the examination of sacroiliac joint biopsy specimens from patients with ankylosing spondylitis.
abstract: OBJECTIVE
  To investigate mechanisms involved in inflammation and new bone formation in the sacroiliac (SI) joints of patients with ankylosing spondylitis (AS).
  
  
  METHODS
  Computed tomography-assisted biopsy of the SI joint was performed in 5 patients with AS with a mean disease duration of 4.5 years and radiographic stage 2-3 disease. Immunohistologic studies were performed with the alkaline phosphatase-anti-alkaline phosphatase technique, and cytokine messenger RNA (mRNA) was detected by in situ hybridization.
  
  
  RESULTS
  Dense cellular infiltrates with varying amounts of CD3+ cells (mean +/- SD 53.3 +/- 24.1%), CD4+ cells (29.7 +/- 17.6%), CD8+ cells (15.8 +/- 11.4%), CD14+ cells (23.6 +/- 16.9%), CD45RO+ cells (48.4 +/- 23.6%), and CD45RA+ cells (4.5 +/- 2.9%) were found in the synovial portion of the SI joints of all 5 patients. In these infiltrates a high amount of tumor necrosis factor alpha (TNF alpha) mRNA and, near the site of new bone formation, a lower amount of transforming growth factor beta (TGF beta) mRNA, were detected, while no message for interleukin-1 was found in the 3 patients examined by this technique.
  
  
  CONCLUSIONS
  The presence of T cells and macrophages was demonstrated in cellular infiltrates in the SI joints of 5 patients with active AS. The finding of abundant TNF alpha message in these joints could have implications regarding potential immunotherapeutic approaches to this disease. TGF beta might be involved in new bone formation in AS.
authors.affiliation: Klinikum Benjamin Franklin, Freie Universität Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Braun
authors.forename: M
authors.initials: M
authors.lastname: Bollow
authors.forename: L
authors.initials: L
authors.lastname: Neure
authors.forename: E
authors.initials: E
authors.lastname: Seipelt
authors.forename: F
authors.initials: F
authors.lastname: Seyrekbasan
authors.forename: H
authors.initials: H
authors.lastname: Herbst
authors.forename: U
authors.initials: U
authors.lastname: Eggens
authors.forename: A
authors.initials: A
authors.lastname: Distler
authors.forename: J
authors.initials: J
authors.lastname: Sieper
mesh_terms: D000328:Adult; D001707:Biopsy, Needle / Q000379:methods; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D013167:Spondylitis, Ankylosing / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D014057:Tomography, X-Ray Computed