beta2-GlycoproteinIELISAisasolidphaseenzymeimmunoassayemployingnativeß2-glycoproteinIhighlypurifiedfromhumanplasmafortheseparatequantitativeandqualitativedetectionofIgGand/orIgMantibodiesagainstß2-glycoproteinIinhumanserum.Anti-ß2-glycoproteinIantibodiesrecognizespecificepitopesonhumanß2-glycoproteinIwhichareexpressedonlywhenß2-glycoproteinIinteractswithlipidmembranesorwhenabsorbedtoothersurfaces(e.g.microtiterplate).Theassayisanaidinthediagnosisandriskofprimaryandsecondaryantiphospholipidsyndrome(APS).Antibodiesagainstß2-glycoproteinIbelongtothegroupofanti-phospholipidantibodiesmainlytargetedagainstcomplexescomposedofnegativelychargedphospholipids(cardiolipine.g)andplasmaproteinslikeß2-glycoproteinI,prothrombin,proteinCorproteinS.Reactivityagainstisolatedß2-glycoproteinIisfound,too.Thusß2-glycoproteinIisdiscussedtobeanautoantigenonitsown.ß2-glycoproteinI,alsocalledapolipoproteinH,isa50kDaß2globulinewhichisassociatedinvivowithlipoprotein,plateletsandphospholipidsandwhichseemstoinhibittheintrinsiccoagulationpathway,theprothrombinaseactivityandtheADP-dependentplateletaggregation.Anti-phospholipidantibodiesarefrequentlyfoundinseraofpatientswithsystemiclupuserythematosusandrelateddiseasesandaretypicalforthesecondarydevelopmentofanantiphospholipidsyndrome(APS).Whilst,anti-phospholipidantibodiesinpatientswithnootherautoimmunediseasescharacterizeaprimaryAPS.Manystudieshaveshownacorrelationbetweentheseautoantibodiesandanenhancedincidenceofthrombosis,thrombocytopeniaandhABItualabortions(asaconsequenceofplacentalinfarction).Theexactmechanismhowpathogenicanti-phospholipidantibodiesinducethrombosishasnotbeenrevealedyet.