title: Elevated levels of the soluble form of bone marrow stromal cell antigen 1 in the sera of patients with severe rheumatoid arthritis.
abstract: OBJECTIVE
  Bone marrow stromal cell antigen 1 (BST-1) is a novel glycosyl phosphatidylinositol-anchored ectoenzyme, which is overexpressed on bone marrow stromal and synovial cell lines derived from patients with rheumatoid arthritis (RA). To investigate the pathophysiologic roles of BST-1 in RA, we established an enzyme-linked immunosorbent assay (ELISA) system to detect the soluble form of BST-1 (sBST-1) and examined levels of sBST-1 in the sera of RA patients.
  
  
  METHODS
  Concentrations of sBST-1 in sera from healthy donors and from patients with RA, osteoarthritis, Sjögren's syndrome, and systemic lupus erythematosus were measured with the ELISA.
  
  
  RESULTS
  In 7% of the RA patient samples (10 of 143), concentrations of serum sBST-1 were higher (approximately 30-50-fold) than in non-RA samples. Serum sBST-1 concentrations showed no correlation with age, C-reactive protein level, or rheumatoid factor level. All RA patients with high concentrations of serum sBST-1 had severe disease with involvement of several large joints.
  
  
  CONCLUSIONS
  We believe the measurement of serum sBST-1 may have prognostic value, but further analysis is necessary to clarify the clinical significance of elevated sBST-1 in RA.
authors.affiliation: Osaka University Medical School, Japan.
authors.forename: B O
authors.initials: BO
authors.lastname: Lee
authors.forename: K
authors.initials: K
authors.lastname: Ishihara
authors.forename: K
authors.initials: K
authors.lastname: Denno
authors.forename: Y
authors.initials: Y
authors.lastname: Kobune
authors.forename: M
authors.initials: M
authors.lastname: Itoh
authors.forename: O
authors.initials: O
authors.lastname: Muraoka
authors.forename: T
authors.initials: T
authors.lastname: Kaisho
authors.forename: T
authors.initials: T
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Ochi
authors.forename: T
authors.initials: T
authors.lastname: Hirano
mesh_terms: D036541:ADP-ribosyl Cyclase; D000328:Adult; D015703:Antigens, CD; D000954:Antigens, Surface / Q000097:blood* / Q000378:metabolism; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology / Q000473:pathology; D002460:Cell Line; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D058851:GPI-Linked Proteins; D006801:Humans; D008562:Membrane Glycoproteins / Q000097:blood* / Q000378:metabolism; D008875:Middle Aged; D017154:Stromal Cells / Q000276:immunology; D013583:Synovial Membrane / Q000276:immunology / Q000473:pathology
chemical_list: D015703:Antigens, CD; D000954:Antigens, Surface; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; D036541:ADP-ribosyl Cyclase; C087521:ADP-ribosyl cyclase 2