title: Gastric B-cell clonal expansion and Helicobacter pylori infection in patients with autoimmune diseases and with dyspepsia. A follow-up study.
abstract: BACKGROUND
  It is not clear whether gastric B-cell clonal expansion, a possible precursor of mucosa-associated lymphatic tissue (MALT) lymphoma, is exclusively linked to Helicobacter pylori infection and virulence.
  
  
  METHODS
  In this study we followed up, for up to 33 months, 16 VDJ polymerase chain reaction-positive patients (4 with dyspepsia, 9 with Sjögren's syndrome, and 3 with other autoimmune diseases). Of these, 12 were H. pylori-positive. In addition, in H. pylori-positive patients we tested whether the serum anti-cag-A (a potential marker of virulence) was preferentially associated with B-cell clonality.
  
  
  RESULTS
  In all but one patient clonality appeared temporally unrelated to H. pylori infection. The prevalence of anti-cagA was not higher in H. pylori/VDJ-positive patients than in controls.
  
  
  CONCLUSIONS
  These data indicate that, in addition to H. pylori, gastric B-cell clonality may be sustained by other agents/mechanisms. Anti-cag-A does not appear to be involved in the pathogenesis of clonality.
authors.affiliation: Dept. of Clinical and Experimental Medicine, School of Medicine, University of Udine, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Sorrentino
authors.forename: G F
authors.initials: GF
authors.lastname: Ferraccioli
authors.forename: S
authors.initials: S
authors.lastname: Devita
authors.forename: A
authors.initials: A
authors.lastname: Labombarda
authors.forename: C
authors.initials: C
authors.lastname: Avellini
authors.forename: A
authors.initials: A
authors.lastname: Ponzetto
authors.forename: C A
authors.initials: CA
authors.lastname: Beltrami
authors.forename: M
authors.initials: M
authors.lastname: Boiocchi
authors.forename: E
authors.initials: E
authors.lastname: Bartoli
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000032:analysis; D000942:Antigens, Bacterial / Q000276:immunology; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology*; D001402:B-Lymphocytes / Q000473:pathology*; D001426:Bacterial Proteins / Q000276:immunology; D002999:Clone Cells; D004415:Dyspepsia / Q000150:complications / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016481:Helicobacter Infections / Q000150:complications / Q000276:immunology*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D013270:Stomach / Q000276:immunology*
chemical_list: D000906:Antibodies; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori