title: Preferential accumulation of activated Th1 cells not only in rheumatoid arthritis but also in osteoarthritis joints.
abstract: OBJECTIVE
  It was previously found that Th1 but not Th17 cells were predominant in the joints of rheumatoid arthritis (RA). To verify whether this is a unique feature of CD4 T cells in RA joints, we performed comparative flow cytometric analysis of CD4 T cells in RA and osteoarthritis (OA) joints.
  
  
  METHODS
  Mononuclear cells were isolated from peripheral blood (PB), synovial membrane (SM), and synovial fluid (SF) from a total of 18 RA and 12 OA patients. The expression of surface molecules and cytokine production of CD4 T cells was examined by a flow cytometer.
  
  
  RESULTS
  Most CD4 T cells in RA joints expressed memory/activation markers, such as CD45RO, HLA-DR, and CD69. CCR5 was highly expressed on CD4 T cells in SF but not in PB or SM. With regard to Th17-related molecules, CD4 T cells expressing CCR6 were not enriched in either SF or SM. In contrast, CD161-positive cells were abundant in the joint, many of which, however, produced interferon-γ but not interleukin 17A. Virtually all T cells in OA joints, although much less numerous than in RA joints, expressed activation markers. Th1 cells were predominant in both OA and RA joints, while there were a few Th17 cells. The frequency of Th17 cells in the joint tended to be lower in OA than RA.
  
  
  CONCLUSIONS
  There was a quantitative but not qualitative difference in CD4 T cells, including the expression of activation markers and cytokine profiles, between RA and OA joints.
authors.affiliation: Division of Host Defence, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan. hisakata@bioreg.kyushu-u.ac.jp
authors.forename: Hisakata
authors.initials: H
authors.lastname: Yamada
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Nakashima
authors.forename: Ken
authors.initials: K
authors.lastname: Okazaki
authors.forename: Taro
authors.initials: T
authors.lastname: Mawatari
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Fukushi
authors.forename: Akiko
authors.initials: A
authors.lastname: Oyamada
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Fujimura
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Iwamoto
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Yoshikai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D015415:Biomarkers / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007596:Joints / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000276:immunology* / Q000473:pathology; D018417:Th1 Cells / Q000166:cytology / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology
chemical_list: D018501:Antirheumatic Agents; D015415:Biomarkers