title: Evaluation of different immunoassays for the detection of antiphospholipid antibodies: report of a wet workshop during the 13th International Congress on Antiphospholipid Antibodies.
abstract: BACKGROUND
  The performance and standardization of anticardiolipin (aCL) and anti-β₂ glycoprotein I antibodies (aβ₂GPI) tests for the confirmation of diagnosis of antiphospholipid syndrome (APS) remain a matter of debate and concern. We evaluated the performance of different ELISAs and other new immunoassays for the detection of aCL and aβ₂GPI in a wet workshop at the 13th International Congress on Antiphospholipid Antibodies in Galveston, TX (April 13th, 2010, APLA 2010).
  
  
  METHODS
  Aliquots of 26 un-identified APS or persistently aPL positive serum samples and 21 controls (9 from healthy individuals and 5 from patients with infectious diseases and 7 with various autoimmune diseases) were distributed to all participants/groups. All serum samples were evaluated in various aCL and aβ₂GPI ELISAs, a chemiluminescent immunoassay, a fluoro-enzyme immunoassay, and in a multiplexed immunoassay system. Monoclonal and polyclonal calibrators were also evaluated.
  
  
  RESULTS
  Although not all the assays reported the titers of aCL and aβ₂GPI in the same units, the correlation of positive titers among the assays was good. All aCL and aβ₂GPI tests showed excellent clinical sensitivities, specificities and positive predictive values and good agreement with respect to the levels of the IgG and IgM antibodies, regardless of assay type, or whether tests were done using automated or "manual" systems.
  
  
  CONCLUSIONS
  New methodologies for the detection of aPL look promising and comparable to currently approved ELISA tests. This study provides evidence of progress of efforts of harmonization of tests used to detect aPL.
authors.affiliation: Universidad Favaloro, Buenos Aires, Argentina. Electronic address: rforastiero@favaloro.edu.ar.
authors.forename: R
authors.initials: R
authors.lastname: Forastiero
authors.affiliation: University of Texas Medical Branch, Galveston, TX, United States.
authors.forename: E
authors.initials: E
authors.lastname: Papalardo
authors.affiliation: Bio-Rad Laboratories, Hercules, CA, United States.
authors.forename: M
authors.initials: M
authors.lastname: Watkins
authors.affiliation: Bio-Rad Laboratories, Hercules, CA, United States.
authors.forename: H
authors.initials: H
authors.lastname: Nguyen
authors.affiliation: Instrumentation Laboratory, Bedford, MA, United States.
authors.forename: C
authors.initials: C
authors.lastname: Quirbach
authors.affiliation: Instrumentation Laboratory, Bedford, MA, United States.
authors.forename: K
authors.initials: K
authors.lastname: Jaskal
authors.affiliation: Phadia, GmbH, Freiburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Kast
authors.affiliation: TheraTest Laboratories, Lombard, United States.
authors.forename: M
authors.initials: M
authors.lastname: Teodorescu
authors.affiliation: INOVA Diagnostics, Inc., San Diego, CA, United States.
authors.forename: G
authors.initials: G
authors.lastname: Lakos
authors.affiliation: INOVA Diagnostics, Inc., San Diego, CA, United States.
authors.forename: W
authors.initials: W
authors.lastname: Binder
authors.affiliation: INOVA Diagnostics, Inc., San Diego, CA, United States.
authors.forename: Z
authors.initials: Z
authors.lastname: Shums
authors.affiliation: INOVA Diagnostics, Inc., San Diego, CA, United States.
authors.forename: V
authors.initials: V
authors.lastname: Nelson
authors.affiliation: INOVA Diagnostics, Inc., San Diego, CA, United States.
authors.forename: G
authors.initials: G
authors.lastname: Norman
authors.affiliation: Biokit SA, Lliçà d'Amunt, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Puig
authors.affiliation: Bio-Rad Laboratories, Hercules, CA, United States.
authors.forename: A
authors.initials: A
authors.lastname: Cox
authors.affiliation: Bio-Rad Laboratories, Hercules, CA, United States.
authors.forename: W
authors.initials: W
authors.lastname: Vandam
authors.affiliation: Bio-Rad Laboratories, Hercules, CA, United States.
authors.forename: J
authors.initials: J
authors.lastname: Hardy
authors.affiliation: University of Texas Medical Branch, Galveston, TX, United States.
authors.forename: S
authors.initials: S
authors.lastname: Pierangeli
mesh_terms: D017152:Antibodies, Antiphospholipid / Q000097:blood* / Q000276:immunology; D016736:Antiphospholipid Syndrome / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D002308:Cardiolipins / Q000276:immunology; D003226:Congresses as Topic; D004493:Education; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007118:Immunoassay; D053482:beta 2-Glycoprotein I / Q000276:immunology
chemical_list: D017152:Antibodies, Antiphospholipid; D002308:Cardiolipins; D053482:beta 2-Glycoprotein I
keywords: Anti-β2 glycoprotein I antibodies; Anticardiolipin antibodies; Antiphospholipid syndrome; Standardization of antiphospholipid antibodies; Wet workshop