Details

Autor(en) / Beteiligte

• Pregnolato, Francesca
• Chighizola, Cecilia B.
• Encabo, Susan
• Shums, Zakera
• Norman, Gary L.
• Tripodi, Armando
• Chantarangkul, Veena
• Bertero, Tiziana
• De Micheli, Valeria
• Borghi, Maria Orietta
• Meroni, Pier Luigi

Titel

Anti-phosphatidylserine/prothrombin antibodies: an additional diagnostic marker for APS?

Ist Teil von

• Immunologic research, 2013-07, Vol.56 (2-3), p.432-438

Ort / Verlag

New York: Springer-Verlag

Erscheinungsjahr

2013

Quelle

MEDLINE

Beschreibungen/Notizen

• Among the diagnostic assays for anti-phospholipid syndrome (APS), lupus anticoagulant (LA) is the strongest predictor of thrombosis; however, it presents several limitations as interference with anticoagulant therapy and poor inter-laboratory agreement. Two-thirds of LA activity is apparently due to antibodies against prothrombin (PT), usually detectable by ELISA. Binding of PT to phosphatidylserine (PS) has been shown to enhance solid-phase anti-PT assay sensitivity. To determine the prevalence of antibodies against PS/PT (aPS/PT) in APS, we tested the semiquantitative QUANTA Lite ® aPS/PT ELISA in a cohort of 80 APS patients. The prevalence of aPS/PT was 81.3 %, rising to 87.6 % when considering LA-positive subjects only. We observed a strong correlation between aPS/PT and LA ( p  = 0.006). To note, APS patients with thrombotic manifestations displayed significantly higher IgG aPS/PT titers compared to 20 aPL asymptomatic carriers ( p  = 0.012). To rule out a possible cross-reactivity of anti-β2 glycoprotein I antibodies (aβ2GPI) with PS/PT complex, we tested two monoclonal aβ2GPI antibodies and an affinity-purified (AP) polyclonal aβ2GPI IgG obtained from the serum of a patient reacting against both β2GPI and PS/PT. The two monoclonal antibodies did not show any reactivity against PS/PT complex, similarly the AP IgGs did not react toward PS/PT antigen while preserved their aβ2GPI activity. Our findings suggest that aPS/PT are a definite antibody population in APS. Moreover, the good correlation between aPS/PT ELISA and LA may support its use as a surrogate test for LA, particularly useful to overcome the technical limitations of the functional assay.