title: Detection of acetylcholine receptor modulating antibodies by flow cytometry.
abstract: OBJECTIVE
  To determine the clinical utility and performance characteristics of a laboratory-adapted flow cytometric method for the detection of acetylcholine receptor (AChR) modulating antibodies in myasthenia gravis (MG).
  
  
  METHODS
  Serum samples from 120 healthy donors and 100 patients with suspected MG were assessed for the ability to reduce surface AChR concentrations (antigenic modulation) in RD (TE671) or DB40 human muscle cell lines by flow cytometry. Reference ranges were established by receiver operating characteristic curve analysis, and results were then compared with those of the current radioimmunoassay (RIA).
  
  
  RESULTS
  Flow cytometric results from the RD cell line had an interpretive threshold of 46% modulation or greater and correlated best (98% sensitivity, 99% specificity) with those of the current RIA.
  
  
  CONCLUSIONS
  The new flow cytometric method using the RD cell platform provided higher quality clinical results, a more robust and efficient assay format, a significant cost savings, and less environmental burden.
authors.affiliation: From the Department of Pathology, University of Utah School of Medicine, Salt Lake City;
authors.forename: Bucky K
authors.initials: BK
authors.lastname: Lozier
authors.affiliation: From the Department of Pathology, University of Utah School of Medicine, Salt Lake City; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT;
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Haven
authors.affiliation: ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT;
authors.forename: Mark E
authors.initials: ME
authors.lastname: Astill
authors.affiliation: From the Department of Pathology, University of Utah School of Medicine, Salt Lake City; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT; Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, and Department of Medicine, University of Utah School of Medicine, Salt Lake City. Harry.Hill@path.utah.edu.
authors.forename: Harry R
authors.initials: HR
authors.lastname: Hill
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal; D019540:Area Under Curve; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000276:immunology; D002460:Cell Line; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D009157:Myasthenia Gravis / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D012372:ROC Curve; D011950:Receptors, Cholinergic / Q000276:immunology*; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D001324:Autoantigens; D011950:Receptors, Cholinergic
keywords: AChR antibodies; Antigenic modulation; Flow cytometry; Myasthenia gravis