title: Lymphocytic infiltration and expression of inducible nitric oxide synthase in human duodenal and colonic mucosa is a characteristic feature of ankylosing spondylitis.
abstract: OBJECTIVE
  In patients with ankylosing spondylitis (AS), inflammatory processes have been detected in the ileal and colonic mucosa. The inducible isoform of nitric oxide synthase (iNOS) may be expressed early in the inflammatory process. We investigated iNOS activity and lymphocytic infiltration in the duodenum and colon in patients with AS and ulcerative colitis compared with controls.
  
  
  METHODS
  Gastroscopy with duodenal biopsies and/or colonoscopy with biopsies were conducted in 42 patients with AS treated or not treated with nonsteroidal antiinflammatory drugs (NSAID), in 15 with ulcerative colitis, and in 46 controls. Lymphocytic infiltration in the lamina propria and intraepithelial infiltration were quantified by histological score. iNOS expression was assessed by immunohistochemistry with monoclonal antibodies, and iNOS activity was determined by radiochemical assay.
  
  
  RESULTS
  Endoscopic examination of the gastroduodenal or colonic mucosa did not reveal macroscopic lesions in the AS patients. In the duodenum, mucosal lymphocytic infiltration was found in 83.3% of the AS group compared to 48.6% of controls (p = 0.02), and was independent of the NSAID intake. Intraepithelial lymphocyte infiltration was increased in both duodenum and colon in AS patients compared to controls. iNOS activity in duodenum and colon and expression of iNOS protein in lamina propria inflammatory cells was increased in AS patients compared to controls.
  
  
  CONCLUSIONS
  Lymphocytic infiltration and iNOS expression and activity were detected in duodenal and colonic mucosa from patients with AS. Such findings may indicate an inflammatory process in the small intestine and colon of patients with AS.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale (INSERM) U99, Department of Gastroenterology, AP-HP Hôpital Henri Mondor, F-94010 Créteil, France. dominique.lamarque@bch.ap-hop-paris.fr
authors.forename: Dominique
authors.initials: D
authors.lastname: Lamarque
authors.forename: Jeanne Tran Van
authors.initials: JT
authors.lastname: Nhieu
authors.forename: Maxime
authors.initials: M
authors.lastname: Breban
authors.forename: Christophe
authors.initials: C
authors.lastname: Bernardeau
authors.forename: Nadine
authors.initials: N
authors.lastname: Martin-Garcia
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Szepes
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Delchier
authors.forename: Brendan
authors.initials: B
authors.lastname: Whittle
authors.forename: Pascal
authors.initials: P
authors.lastname: Claudepierre
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D016022:Case-Control Studies; D002465:Cell Movement; D003106:Colon / Q000201:enzymology / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D004386:Duodenum / Q000201:enzymology / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D005773:Gastroscopy; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007413:Intestinal Mucosa / Q000201:enzymology* / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D008214:Lymphocytes / Q000473:pathology* / Q000502:physiology; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D013167:Spondylitis, Ankylosing / Q000201:enzymology* / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007376:Interleukin-2; D016753:Interleukin-10; D007371:Interferon-gamma; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II