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A case of a 37-year-old pregnant patient with antiphospholipid syndrome (APS), who has a medical history of both thrombosis and recurrent fetal loss, is presented. She was treated with predonisolone and fixed-dose unfractionated heparin (UFH) infusion, followed by plasmaphereses and fixed-dose low-molecular-weight heparin infusion during her fourth pregnancy. Unfortunately, this treatment did not have beneficial effects, resulting in intrauterine growth restriction and finally neonatal death. Continuous intravenous UFH infusion and low-dose aspirin were administrated under the monitoring of the activated partial thromboplastin time to achieve a target level of 120 s during her fifth pregnancy. A healthy baby weighing 1818 g at birth was delivered by Cesarean section at the 34th week of pregnancy. High-dose UFH infusion may be considered to be one of the preferable options to manage pregnant patients with refractory APS.

Antibodies against prothrombin are detected by enzyme immunoassays (EIA) in sera of patients with antiphospholipid syndrome (APS). However, there are two methods for antiprothrombin EIA; one that uses high binding plates (aPT-A), and another that utilizes phosphatidylserine bound plates (aPS/PT). We aimed to evaluate and compare aPT-A and aPS/PT in a clinical setting. We performed EIA for anti-PT, anti-PS/PT, IgG, and IgM anticardiolipin antibodies (aCL), and IgG beta2-glycoprotein I-dependent aCL (abeta2GPI/CL) with serum samples from 139 systemic lupus erythematosus (SLE) patients (16 with history of at least one thrombotic episode) and 148 controls. We observed that: (1) although titers of anti-PT and anti-PS/PT were significantly related with each other (P < 0.0001, rho = 0.548), titer of anti-PT and anti-PS/PT differed greatly in some samples; (2) odds ratio and 95% confidence interval for each assay was 3.556 (1.221-10.355) for aPT-A, 4.591 (1.555-15.560) for aPS/PT, 4.204 (1.250-14.148) for IgG aCL, 1.809 (0.354-9.232) for IgM aCL, and 7.246 (2.391-21.966) for abeta2GPI/CL. We conclude that, while all EIA performed in this study except IgM aCL are of potential value in assessing the risk of thrombosis, aPS/PT and abeta2GPI/CL seemed to be highly valuable in clinical practice, and that autoantibodies detected by anti-PT and anti-PS/PT are not completely identical.

Objective: Impaired fibrinolytical outcomes may be one of the pathogenic factors for thrombotic events in patients with antiphospholipid antibodies (aPL). We investigated the consequences of the gene polymorphisms of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) in patients positive for aPL., Methods: Seventy-seven Japanese and 82 British patients with aPL were examined for Alu-repeat insertion (I)/deletion (D) polymorphism of the tPA gene by polymerase chain reaction (PCR), and 4G/5G polymorphism in the PAI-1 promoter gene by site-directed mutagenesis-PCR and restriction fragment length polymorphism analysis. Correlations between these polymorphisms and clinical symptoms of antiphospholipid syndrome (APS) (arterial thrombosis, venous thrombosis, miscarriage) were analyzed., Results: Significant differences in the allele frequencies of these genes did not exist between patients and controls. There was no significant correlation between these gene polymorphisms and clinical symptoms of APS in patients with aPL., Conclusion: Polymorphisms of the tPA or PAI-1 genes probably do not significantly influence the risk of anerial thrombosis, venous thrombosis, or pregnancy morbidity in patients with aPL.

Binding of β2-glycoprotein I (β2-GPI)-dependent anticardiolipin antibodies (aCL) derived from antiphospholipid syndrome (APS) is significantly reduced in aCL ELISA due to loss of the phospholipid (PL) binding property of β2-GPI by plasmin treatment. In the present study, the treatment generated a nicked form of β2-GPI and resulted in loss of antigenicity for the autoantibodies detected in ELISA, using an β2-GPI directly adsorbed polyoxygenated carboxylated plate, the assay system of which was not related to PL binding. The nicked form bound to neither Cu2+-oxidized low-density lipoprotein (oxLDL) nor to β2-GPI-specific lipid ligands isolated from oxLDL, the result being a complete loss of subsequent binding of anti-β2-GPI autoantibodies. The conformational change in the nicked domain V was predicted from its intact structure determined by an X-ray analysis (implemented in Protein Data Bank: 1C1Z), molecular modeling and epitope mapping of a monoclonal anti-β2-GPI antibody, i.e. Cof-18, which recognizes the related structure. The analysis revealed that novel hydrophobic and electrostatic interactions appeared in domain V after the cleavage, thereby affecting the PL binding of β2-GPI. Such a conformational change may have important implications for exposure of cryptic epitopes located in the domains such as domain IV. [ABSTRACT FROM PUBLISHER]