Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02749 (beta2-glycoprotein I)
 836 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe the case of a 39-year-old woman who suffered two iliofemoral venous thromboses, a cerebral ischemic infarct and recurrent fetal loss. Initial studies showed high levels of antiphospholipid antibodies (APAs) and a moderate thrombocytopenia. After her second miscarriage, laboratory diagnosis revealed that the woman was heterozygous for the factor V Leiden mutation and had a functional protein S deficiency as well as anti-protein S and anti-beta 2-glycoprotein I antibodies. The impairment of the protein C pathway at various points could well explain the recurrent thromboses in the patient and supports the role of a disturbed protein C system in the pathophysiology of thrombosis in patients with APAs.
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PMID:Factor V Leiden and antibodies against phospholipids and protein S in a young woman with recurrent thromboses and abortion. 1009 95

Congenital and acquired thrombophilia are associated with an increased risk of pregnancy-associated venous thrombosis and fetal loss. Two hundred eighty-nine patients with a history of recurrent spontaneous abortion were subjected to screening examinations for the etiology of these abortions. Endocrine abnormality (28.0%), uterine abnormality (10.4%), autoimmune diseases (1.4%), antiphospholipid antibody syndrome (4.5%), and balanced type chromosome translocation (4.2%) were found as underlying causes of recurrent abortions, and the remaining 55.0% of the 289 patients were classified as having an unexplained etiology. Congenital thrombophilia such as protein C (PC) deficiency, protein S (PS) deficiency, antithrombin deficiency, and factor V Leiden mutation was not frequently detected; only one patient had PS deficiency. A reduced factor XII activity was found at a frequency of 4.2%. The frequency of methylene tetrahydrofolate reductase gene C677T mutation in recurrent aborters (0.38) was the same as that found in a fertile control group. Although the prevalence of anti-beta2-glycoprotein I antibody (abeta2-GPI) syndrome was very low (1.7%), patients with a high titer of immunoglobulin G (IgG) class abeta2-GPI, despite anticoagulation therapy, experienced severe fetomaternal complications in subsequent pregnancies. The rate (13.8%) of positive tests for serum IgA class abeta2-GPI in patients with unexplained etiology was higher than that in the controls (0%) (P < .05). We conclude that congenital thrombophilia is rare in Japanese patients who had experienced consecutive spontaneous abortions.
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PMID:Recurrent pregnancy loss: etiology of thrombophilia. 1137 65

Venous thromboembolism (VTE) is one of the common manifestations in the anti-phospholipid (aPL) syndrome. We examined the levels of IgG antibodies (Abs) to beta2-glycoprotein I (beta2-GP I) and prothrombin, lupus anticoagulant (LA) activity, activated protein C resistance (APC-R), and factor V Leiden in 96 patients with systemic lupus erythematosus (SLE); 19 with VTE and 77 without VTE. Acquired APC-R, which was not found in any patient with the factor V Leiden mutation, was present in 33 (34.4%) out of the 96 patients with SLE. The presence of acquired APC-R was a strong risk factor for VTE. The SLE patients were divided into four groups according to the results of enzyme-linked immunosorbent assay (ELISA) and LA activity for each aPL Abs: ELISA+, LA+; ELISA+, LA-; ELISA-, LA+; and ELISA-, LA-. A significant association was observed between APC-R and the co-existence of anti-beta2-GP I Abs and LA activity or of anti-prothrombin Abs and LA activity. There was no association between APC-R and the presence of anti-beta2-GP I Abs, anti-prothrombin Abs, or LA activity alone. However, when multivariate logistical regression analysis was performed, it was clear that only the co-existence of anti-prothrombin and LA activity was a significant risk factor for APC-R. These findings indicate that the co-existence of anti-prothrombin Abs and LA activity may be an important factor in the pathogenesis of acquired APC-R in patients with SLE.
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PMID:Acquired activated protein C resistance is associated with the co-existence of anti-prothrombin antibodies and lupus anticoagulant activity in patients with systemic lupus erythematosus. 1271 80

Anti-phospholipid (aPL) antibodies (Abs) are well known to be associated with thromboembolic events in patients with systemic lupus erythematosus (SLE). However, the clinical relevance of a PL Abs in patients without SLE (non-SLE) who have venous thromboembolism remains unclear. We evaluated 143 non-SLE patients with a first episode of clinically suspected deep vein thrombosis (DVT) by using objective tests for diagnosing DVT and laboratory tests including the activated protein C resistance (APC-R) test, the factor V Leiden test, and various aPL Abs. The prevalence of acquired APC-R, in which case there was no factor V Leiden mutation, was significantly higher in patients with DVT (15/58 cases, 25.9%, p < 0.0001) than in those without DVT (3/80 cases, 3.7%), and confirmed that acquired APC-R was a strong risk factor for DVT (odds ratio [OR], 8.95; 95% confidence intervals [CI], 2.45-32.7; p < 0.001). Multivariate logistic analysis revealed that the presence of LA, aCL, anti-beta2-glycoprotein I, anti-prothrombin and anti-protein C Abs was not reliable as a risk factor for DVT in non-SLE patients, and that the presence of anti-protein S Abs was the most significant risk factor for DVT (OR, 5.88; 95% CI, 1.96-17.7; p < 0.002). Furthermore, the presence of anti-protein S Abs was strongly associated with acquired APC-R (OR, 57.8; 95% CI, 8.53-391; p < 0.0001). These results suggest that acquired APC-R may reflect functional interference by anti-protein S Abs of the protein C pathway, which action may represent an important mechanism for the development DVT in non-SLE patients.
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PMID:Acquired activated protein C resistance associated with anti-protein S antibody as a strong risk factor for DVT in non-SLE patients. 1242 83

Antiphospholipid antibodies (aPL) may induce acquired activated protein C resistance (acquired APCR). The role of acquired APCR in patients with systemic lupus erythematosus (SLE) is not well known. To evaluate the prevalence of acquired APCR and its association with clinical manifestations we studied 103 consecutive SLE patients and 103 matched controls. APCR in the undiluted test and after dilution in factor V deficient plasma, factor V Leiden, protein C and S, lupus anticoagulant, and anti-cardiolipin, anti-beta2-glycoprotein I and anti-prothrombin antibodies were determined. Factor V Leiden was found in 4% in both patients and controls. The prevalence of acquired APCR was 22% for the undiluted assay and 17% in the diluted test. In SLE patients, acquired APCR was associated with aPL (39 vs 13% in undiluted assay, P = 0.007; and 33 vs 7% in the diluted test, P = 0.001). Arterial thromboses were found in 24% of patients with acquired APCR and in 6% of patients without (P = 0.04). However, no relationship was found with venous thrombosis. Acquired APCR was also associated with pregnancy losses: miscarriages in 70% of women with acquired APCR vs 32% in those without (P=0.03). Thus, in SLE patients acquired APCR seems to be associated with increased prevalence of arterial thrombosis and pregnancy losses.
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PMID:Clinical significance of acquired activated protein C resistance in patients with systemic lupus erythematosus. 1247 3

The risk of thromboembolism during oral contraceptive (OC) use is increased among factor V Leiden (FVL) carriers compared to women with wild-type genotype of the gene for coagulation factor V (FV). The carrier frequency in the general population is too high for FVL alone to be responsible for the reported association. Additional risk factors may be required to explain the increased risk of thromboembolism of carriers during OC use. We conducted a case-control study to compare the titer of anti-beta2-glycoprotein I immunoglobulin G (IgG) and the frequency of elevated titer of IgG type anti-beta2-glycoprotein I antibody between FVL carriers and individuals with FV wild-type genotype with and without pill use. An asymptomatic population of 313 unrelated nonpregnant women were screened for FVL and for the presence of anti-beta2-glycoprotein I IgG antibody. Sixty-six women were FVL carriers and 247 had normal genotype. One-hundred and thirty-five women used OC at the time of screening and 178 did not. Among FVL carriers, OC pill users had a higher mean anti-beta2-glycoprotein I IgG titer than nonusers (9.2 SGU/mL vs. 4.7 SGU/mL, p = 0.0485). Among women with FV wild-type genotype, there was no significant difference in anti-beta2-glycoprotein I IgG titers between users and nonusers of OCs (6.4 SGU/mL and 6.0 SGU/mL, respectively; p = 0.7010). The odds of an elevated anti-beta2-glycoprotein I IgG titer during OC use in FVL heterozygous women was 2.41 (95% confidence interval: 0.79-7.39) relative to users with-type genotype. FVL may contribute to the development of elevated titer of IgG type anti-beta2-glycoprotein I antibody during OC use. The elevated titer of IgG type anti-beta2-glycoprotein I antibody may select women among FVL carriers during OC use with an increased risk of thromboembolism.
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PMID:Increased titer of anti-beta2-glycoprotein I IgG antibody among factor V Leiden carriers during oral contraceptive use. 1472 Jun 16

Thrombophilia can be defined as an increased tendency to thrombosis. There are several defined risk factors for thrombosis, and these are generally separated into acquired and congenital factors. Congenital risk factors include deficiencies or defects in natural anticoagulants, such as antithrombin, protein C and protein S, and genetic polymorphisms such as prothrombin G20210A and the cleavage-resistant factor mutation, factor V Leiden, which leads to a condition known as activated protein C resistance. Acquired risk factors include antiphospholipid antibodies, detected as lupus anticoagulants, and/or anticardiolipin or anti-beta2-glycoprotein I antibodies. Elevated homocysteine, immobility, increasing age, surgery, cancer, poor nutrition, pregnancy, high levels of clotting factors, and use of oral contraceptives and hormone replacement therapy comprise other risk factors. Each of these constitutes an element of increased risk, which is compounded when concomitant. There is ongoing debate regarding relative and compound risks, the value of laboratory screening, whom to screen for with these markers, and the form and duration of clinical management. This report briefly explores, from a scientist's perspective, some important issues that are sometimes overlooked.
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PMID:Diagnostic issues in thrombophilia: a laboratory scientist's view. 1570 70

The objective of this study was to clarify the roles of anti-phospholipid antibodies (aPLs) in the pathogenesis of acquired activated protein C resistance (APC-R) in patients with systemic lupus erythematosus (SLE). We examined several aPLs levels (lupus anticoagulant, anti-cardiolipin antibodies, anti-beta2-glycoprotein I antibodies, anti-protein C antibodies, and anti-protein S antibodies), the APC-R test, and the factor V Leiden test in 85 SLE patients. Acquired APC-R, which was not found in any patient with the factor V Leiden mutation, was present in 26 (30.6%) of 85 patients, and confirmed that acquired APC-R was a significant risk factor for thromboembolic complications [odd ratio (OR), 3.36; 95% confidence interval (CI), 1.24-9.11]. Multivariate logistic analysis revealed that both LA and anti-PS strongly associated with the presence of APC-R, and that the correlation between anti-PS and APC-R was much stronger (OR, 46.7; 95%CI, 6.99-311) than that between LA and APC-R (OR, 11.3; 95%CI, 2.26-57.0). Furthermore, the mean value of APC sensitivity ratios was significantly lower in SLE patients with anti-PS (mean +/- SD, 1.68 +/- 0.37, p < 0.0001) than in those without anti-PS (2.23 +/- 0.40). These results suggest that acquired APC-R is most strongly attributable to functional interference of the APC pathway by anti-PS, which contribute to risk of thromboembolic complications.
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PMID:Acquired activated protein C resistance is associated with IgG antibodies to protein S in patients with systemic lupus erythematosus. 1912 22