title: Human mucosyl lymphocyte marker expression in synovial fluid lymphocytes of patient with rheumatoid arthritis.
abstract: OBJECTIVE
  Human mucosyl lymphocyte marker (HML-1) antigen is an activation antigen and adhesion molecule of the beta 7 integrin family, which is generally restricted to T cells found in the intestinal epithelium. Expression of the membrane antigen as defined by the monoclonal antibody HML-1 was studied on peripheral blood (PB) lymphocytes and synovial fluid (SF) lymphocytes in 10 patients with rheumatoid arthritis (RA) and in a control group of patients with osteoarthritis (OA).
  
  
  METHODS
  Double fluorescence activated flow cytometry was used to assess HML-1 expression with T cell subtype antigens (CD3, CD4, CD8) or activation markers interleukin 2 receptor (IL-2R) (CD25), HLA-DR, and lymphocyte function associated antigen (LFA-1) (CD11a) were assessed by flow cytometry.
  
  
  RESULTS
  HML-1 antigen expression in PB lymphocytes of patients with RA (7.3%) was found to be comparable to the control group (6.4%). In contrast, 25.4% (range 14-43%) of SF lymphocytes expressed HML-1 antigen, compared to 13.6% of SF lymphocytes in patients with OA (p < 0.001). In RA, 62% of HML-1 positive cells from SF lymphocytes were the CD8 subtype, compared to 10.6% of PB lymphocytes (p < 0.003), and 18% of control SF lymphocytes (p < 0.05). Furthermore, HML-1 antigen and HLA-DR antigen were coexpressed in 75% of RA SF lymphocytes compared to 29.6% of control SF lymphocytes (p < 0.01). In contrast, coexpression of LFA-1 and the Il-2R did not differ from that of control.
  
  
  CONCLUSIONS
  We describe overexpression of the adhesion molecule HML-1 in SF lymphocytes of patients with RA, preferentially in the CD8 subset. These results suggest a similarity between the expression of activation antigens in SF lymphocytes of patients with RA and T lymphocytes present in the intestinal epithelium.
authors.affiliation: Service d'Immuno-Rhumatologie, Centre Gui-de-Chauliac, Montpellier, France.
authors.forename: C
authors.initials: C
authors.lastname: Jorgensen
authors.forename: A
authors.initials: A
authors.lastname: Travaglio-Encinoza
authors.forename: C
authors.initials: C
authors.lastname: Bologna
authors.forename: A D
authors.initials: AD
authors.lastname: D'Angeac
authors.forename: T
authors.initials: T
authors.lastname: Reme
authors.forename: J
authors.initials: J
authors.lastname: Sany
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D016023:Integrins / Q000032:analysis* / Q000276:immunology; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013582:Synovial Fluid / Q000276:immunology*
chemical_list: D006684:HLA-DR Antigens; D016023:Integrins; D016169:Lymphocyte Function-Associated Antigen-1; D015375:Receptors, Interleukin-2; C070709:integrin alphaEbeta7