title: Antibodies to Phosphatidylserine/Prothrombin Complex in Antiphospholipid Syndrome: Analytical and Clinical Perspectives.
abstract: Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and/or pregnancy-related morbidity accompanied by persistently positive antiphospholipid antibodies (aPL). Current laboratory criteria for APS classification recommend testing for lupus anticoagulant as well as IgG and IgM anticardiolipin, and beta-2 glycoprotein I (anti-β2GPI) antibodies. However, there appears to be a subset of patients with classical APS manifestations who test negative for the recommended criteria aPL tests. While acknowledging that such patients may have clinical features that are not of an autoimmune etiology, experts also speculate that these "seronegative" patients may test negative for relevant autoantibodies as a result of a lack of harmonization and/or standardization. Alternatively, they may have aPL that target other antigens involved in the pathogenesis of APS. In the latter, autoantibodies that recognize a phosphatidylserine/prothrombin (PS/PT) complex have been reported to be associated with APS and may have diagnostic relevance. This review highlights analytical and clinical attributes associated with PS/PT antibodies, taking into consideration the performance characteristics of criteria aPL tests in APS with specific recommendations for harmonization and standardization efforts.
authors.affiliation: Department of Pathology, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Peterson
authors.affiliation: Rheumatology/Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA.
authors.forename: Rohan
authors.initials: R
authors.lastname: Willis
authors.affiliation: University of the West Indies, Mona, Kingston, Jamaica.
authors.forename: E Nigel
authors.initials: EN
authors.lastname: Harris
authors.affiliation: Maternal Fetal Medicine, University of Utah and Intermountain Healthcare, Salt Lake City, Utah, USA.
authors.forename: Ware D
authors.initials: WD
authors.lastname: Branch
authors.affiliation: Department of Pathology, University of Utah, Salt Lake City, Utah, USA; ARUP Laboratories, Institute of Clinical and Experimental Pathology, Salt Lake City, Utah, USA. Electronic address: anne.tebo@hsc.utah.edu.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Tebo
mesh_terms: D000906:Antibodies / Q000276:immunology*; D016736:Antiphospholipid Syndrome / Q000175:diagnosis* / Q000276:immunology*; D015415:Biomarkers; D006801:Humans; D010718:Phosphatidylserines / Q000737:chemistry / Q000378:metabolism*; D011516:Prothrombin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000906:Antibodies; D015415:Biomarkers; D010718:Phosphatidylserines; D011516:Prothrombin
keywords: Antiphospholipid antibodies; Antiphospholipid syndrome; Immunoassays; aPS/PT