title: Identification of streptococcal proteins reacting with sera from Behçet's disease and rheumatic disorders.
abstract: OBJECTIVE
  We evaluated the reactivity of sera from Behçet's disease (BD), systemic lupus erythematosus (SLE), dermatomyositis (DM), rheumatoid arthritis (RA), and Takayasu's arteritis (TA) patients against human α-enolase and streptococcal α-enolase, and identified additional streptococcal antigens.
  
  
  METHODS
  Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were performed using sera from patients with BD, SLE, DM, RA, and TA and healthy volunteers (control) against human α-enolase and streptococcal α-enolase. Immunoblot analysis and matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry were used to identify and recombine other streptococcal antigens.
  
  
  RESULTS
  Specific positive signals against recombinant human α-enolase were detected by IgM ELISA of serum samples from 50% of BD, 14.3% of SLE, 57.1% of DM, 42.9% of RA, and 57.1% of TA patients. Specific positive signals against streptococcal α-enolase were detected from 42.9% of BD, 14.3% of DM, and 14.3% of TA patients. No SLE and RA sera reacted against streptococcal α-enolase antigen. Streptococcal proteins reacting with sera were identified as hypothetical protein (HP) for SLE and DM patients, acid phosphatase (AP) for RA patients, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for TA patients.
  
  
  CONCLUSIONS
  We observed that RA patients did not present serum reactivity against either HP or GAPDH though BD, SLE, DM, and TA patients did. Also, AP reacted with sera from BD, SLE, DM, RA, and TA patients.
authors.affiliation: Department of Dermatology, Yonsei University College of Medicine, Seoul, Korea. sbcho@yuhs.ac
authors.forename: Sung Bin
authors.initials: SB
authors.lastname: Cho
authors.forename: Ju Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Keun Jae
authors.initials: KJ
authors.lastname: Ahn
authors.forename: Suhyun
authors.initials: S
authors.lastname: Cho
authors.forename: Yong-Beom
authors.initials: YB
authors.lastname: Park
authors.forename: Soo-Kon
authors.initials: SK
authors.lastname: Lee
authors.forename: Dongsik
authors.initials: D
authors.lastname: Bang
authors.forename: Kwang Hoon
authors.initials: KH
authors.lastname: Lee
mesh_terms: D000135:Acid Phosphatase / Q000276:immunology; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology*; D001528:Behcet Syndrome / Q000097:blood* / Q000276:immunology; D016022:Case-Control Studies; D003882:Dermatomyositis / Q000097:blood* / Q000276:immunology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000276:immunology; D010751:Phosphopyruvate Hydratase / Q000276:immunology; D013298:Streptococcus sanguis; D013625:Takayasu Arteritis / Q000097:blood / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D000135:Acid Phosphatase; D010751:Phosphopyruvate Hydratase