title: B1a lymphocytes in the rectal mucosa of ulcerative colitis patients.
abstract: OBJECTIVE
  To assess B1a cell expression in the rectal mucosa of ulcerative colitis (UC) patients in comparison with healthy controls.
  
  
  METHODS
  Rectal mucosa biopsies were collected from 15 UC patients and 17 healthy controls. CD5(+) B cells were analysed by three colour flow cytometry from rectal mucosal samples after mechanical disaggregation by Medimachine(®). Immunohistochemical analysis of B and T lymphocytes was also performed. Correlations between, on the one hand, rectal B1a cell concentrations and, on the other, erythrocyte sedimentation rate and C-reactive protein levels and clinical, endoscopic and histological disease activity indices were evaluated.
  
  
  RESULTS
  Rectal B-lymphocyte (CD19(+)/CD45(+)) rate and concentration were higher in UC patients compared with those in healthy controls (47.85% ± 3.12% vs 26.10% ± 3.40%, P = 0.001 and 501 ± 91 cells/mm(2) vs 117 ± 18 cells/mm(2), P < 0.001); Rectal B1a cell density (CD5(+)CD19(+)) was higher in UC patients than in healthy controls (85 ± 15 cells/mm(2) vs 31 ± 6.7 cells/mm(2), P = 0.009). Rectal B1a cell (CD5/CD19(+)) rate correlated inversely with endoscopic classification (Rs = -0.637, P < 0.05).
  
  
  CONCLUSIONS
  B1a lymphocytes seem to be involved in the pathogenesis of UC, however, the role they play in its early phases and in disease activity, have yet to be defined.
authors.affiliation: Department of Surgical and Gastroenterological Sciences, University of Padova, Via Giustiniani 2, 35128 Padova, Italy. linopolese@hotmail.com
authors.forename: Lino
authors.initials: L
authors.lastname: Polese
authors.forename: Riccardo
authors.initials: R
authors.lastname: Boetto
authors.forename: Giuseppe
authors.initials: G
authors.lastname: De Franchis
authors.forename: Imerio
authors.initials: I
authors.lastname: Angriman
authors.forename: Andrea
authors.initials: A
authors.lastname: Porzionato
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Norberto
authors.forename: Giacomo Carlo
authors.initials: GC
authors.lastname: Sturniolo
authors.forename: Veronica
authors.initials: V
authors.lastname: Macchi
authors.forename: Raffaele
authors.initials: R
authors.lastname: De Caro
authors.forename: Stefano
authors.initials: S
authors.lastname: Merigliano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001706:Biopsy; D003093:Colitis, Ulcerative / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007413:Intestinal Mucosa / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012007:Rectum / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D055815:Young Adult
chemical_list: D015703:Antigens, CD