title: Staphylococcal Enterotoxin A Detection from Rheumatoid Arthritis Patients' Blood and Synovial Fluid.
abstract: BACKGROUND
  Direct detection of microbial super antigens in synovial fluid of patients with rheumatoid arthritis may be able to guide to the design of cost-effective therapies. The purpose of this study was to assess the existence of Staphylococcal enterotoxin A (superantigen A) in the synovial fluid of patients with RA by the PCR and ELISA methods.
  
  
  METHODS
  This experimental study was conducted on the synovial fluid of 103 RA patients from Baqiyatallah University of Medical Sciences' Rheumatology Clinic in Tehran, Iran in 2011-2014. Bacterial cultures, polymerase chain reaction with specific primer pairs and enzyme-linked immunosorbent assay (ELISA) methods were used. The PCR products were subjected to sequence as a confirmatory molecular method results. The data were descriptively analyzed by SPSS Version 19.
  
  
  RESULTS
  The bacteriological study result indicated that, in four cases (3.8%) of the patients, bacterial strains were isolated. The result of PCR molecular method for staphylococcal enterotoxin A gene showed that, 42 of the patients (40.7%) tested positive for the ent A gene. The results of ELISA were positive for staphylococcal enterotoxin A (superantigen A) in 51 cases (49.51%) of the patients' synovial fluids. The results indicated that the possibility of detecting superantigen A in the SF of RA patients, but the origin of the enterotoxin A gene remained unknown.
  
  
  CONCLUSIONS
  The findings of this study may be able to alter the actual theory on the pathogenesis, diagnosis, and treatment of RA patients. In addition, the results have shown the probability of an endogenous origin for the involved superantigen A in RA patients' synovial fluids.
authors.affiliation: Ph.D. of Medical Microbiology, Professor, Department of Virology and Bacteriology, and Clinical Development Medical Center of Baqiyatallah Hospital, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Ramezan Ali
authors.initials: RA
authors.lastname: Ataee
authors.affiliation: M.Sc. of Microbiology, Researcher, Department of Virology and Bacteriology, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Mahboobeh Sadat
authors.initials: MS
authors.lastname: Kahani
authors.affiliation: M.D. of Rheumatology, Clinical Development Medical Center of Baqiyatallah Hospital and Department of Rheumatology, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Gholam Hossein
authors.initials: GH
authors.lastname: Alishiri
authors.affiliation: Ph.D. of Biology, Assistant Professor, Research Center of Biology, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Zyenab
authors.initials: Z
authors.lastname: Ahamadi
keywords: ELISA; PCR; rheumatoid arthritis; staphylococcal enterotoxin A; synovial fluid