title: Expression of macrophage markers by a population of T cells obtained from synovial fluid of a subgroup of patients with juvenile rheumatoid arthritis.
abstract: OBJECTIVE
  To characterize distinctive lymphoid cell populations in the synovial fluid (SF) of patients with juvenile rheumatoid arthritis (JRA) that have the specific ability to display monocytic markers when cultured in vitro.
  
  
  METHODS
  Mononuclear cells obtained from SF of patients with JRA and depleted of adherent macrophages were cultured in vitro in RPMI 1640 medium supplemented with only fetal calf serum (FCS). Phenotypic evaluation of these cells was by flow cytometry and immunohistochemical analysis was by specific fluorochrome labeled antibodies.
  
  
  RESULTS
  T cells from a JRA subgroup displayed some typical macrophage attributes, i.e., abundant cytoplasm, adherence to plastic, and phagocytosis of latex beads when cultured in vitro. These cells have the ability to survive in culture for several weeks in RPMI 1640 medium containing only 10% FCS. The macrophage-like T cells rosetted with sheep red blood cells and proliferated when stimulated with phytohemagglutinin or anti-CD3, indicating functional T cell responses.
  
  
  CONCLUSIONS
  Our data indicate that a population of T cells obtained from the SF of a subgroup of patients with JRA exhibited characteristics of macrophages, yet retained their CD3 and T cell receptor expression. Whether this promiscuous behavior is caused by malignant transformation of lymphoid precursor cells or is induced by the concerted effect of a myriad of cytokines and growth factors present in the SF remains unknown. The presence of these cells in the SF of 2 patients with JRA with different onset types raises the question of their function and significance in an autoimmune disorder such as JRA.
authors.affiliation: Pediatric Research Institute, Pathology Department, Saint Louis University, Missouri, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Khalkhali-Ellis
authors.forename: S T
authors.initials: ST
authors.lastname: Roodman
authors.forename: A P
authors.initials: AP
authors.lastname: Knutsen
authors.forename: K R
authors.initials: KR
authors.lastname: Mueller
authors.forename: B
authors.initials: B
authors.lastname: Chauhan
authors.forename: T L
authors.initials: TL
authors.lastname: Moore
authors.forename: M J
authors.initials: MJ
authors.lastname: Hendrix
mesh_terms: D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000378:metabolism*; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D001171:Arthritis, Juvenile / Q000378:metabolism*; D017252:CD3 Complex / Q000276:immunology / Q000378:metabolism; D016827:CD8 Antigens / Q000378:metabolism; D002448:Cell Adhesion; D002478:Cells, Cultured; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism; D010835:Phytohemagglutinins / Q000494:pharmacology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism; D013167:Spondylitis, Ankylosing / Q000378:metabolism; D013582:Synovial Fluid / Q000166:cytology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D017252:CD3 Complex; D016827:CD8 Antigens; D017493:Leukocyte Common Antigens; D010835:Phytohemagglutinins; D016693:Receptors, Antigen, T-Cell, alpha-beta; C067980:CD68 antigen, human; D000097382:CD68 Molecule