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Pontara E, Cattini MG, Bison E, Cheng C, Denas G, Pengo V. Antiphospholipid syndrome: Reversal of antiphosphatidylserine/prothrombin-induced activated protein C resistance. Thromb Res 2022; 218:17-23. [PMID: 35973396 DOI: 10.1016/j.thromres.2022.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/28/2022] [Accepted: 08/08/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND Anti-phosphatidylserine/prothrombin (aPS/PT) antibodies are the major contributor to activated Protein C resistance (APC-R) in tetra-positive thrombotic high-risk patients with Antiphospholipid Syndrome (APS). OBJECTIVES To evaluate the role of phospholipids (PL) on aPS/PT mediated APC-R. PATIENTS/METHODS Total IgG were purified from plasma of 6 tetra-positive patients and IgG aPS/PT were affinity-purified from 3 of these patients. Purified material was spiked into Normal Pooled Plasma (NPP) and tested for APC-R in thrombin generation assay and in Factor Va inactivation assay using increasing amounts of phospholipids. RESULTS AND CONCLUSIONS Total IgG showed APC-R at low PL concentration (1.5 μg/mL) that disappeared at increasing PL concentrations (5.8, 11.6 and 46.6 μg/mL). In the same way, affinity purified aPS/PT showed a robust (59 %, 52 %, 36 %) APC-R in patients #4, #5 and #6, respectively at low PL concentration (1.5 μg/mL) that was completely reversed at higher concentration (11.6 μg/mL). The inactivation of FVa by activated Protein C (aPC) was impaired in the presence of aPS/PT at low aPL concentration and reversed by increasing amounts of PL. These data point out the relevance of PL in reversing APC-R in this 'in vitro' system. The mechanism for reversal might be explained by loss of PL availability for aPC. These results may give some insight into the pathogenesis of thrombosis or suggestions for alternative treatments.
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Affiliation(s)
- Elena Pontara
- Thrombosis Research Laboratory, University of Padova, Padova, Italy
| | | | - Elisa Bison
- Thrombosis Research Laboratory, University of Padova, Padova, Italy
| | - Chunyan Cheng
- Thrombosis Research Laboratory, University of Padova, Padova, Italy
| | - Gentian Denas
- Thrombosis Research Laboratory, University of Padova, Padova, Italy
| | - Vittorio Pengo
- Thrombosis Research Laboratory, University of Padova, Padova, Italy; Arianna Foundation on Anticoagulation, Bologna, Italy.
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Pengo V. Interaction between Antiphospholipid Antibodies and Protein C Anticoagulant Pathway: A Narrative Review. Semin Thromb Hemost 2022; 48:971-977. [PMID: 35021251 DOI: 10.1055/s-0041-1742083] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Thrombotic antiphospholipid syndrome (APS) is a condition in which thrombosis in venous, arterial, and/or small vessels is ascribed to the presence of antiphospholipid antibodies (aPL). Among the various proposed pathogenic theories to explain thrombotic APS, those involving the interaction between aPL and the protein C system have gained much consensus. Indeed, robust data show an acquired activated protein C resistance (APC-R) in these patients. The role of aPL in this impairment is clear, but the mechanism of action is uncertain, as the type of aPL and to what extent aPL are involved remains a gray area. Lupus anticoagulant (LA) is often associated with APC-R, but antibodies generating LA comprise those directed to β2-glycoprotein I and antiphosphatidylserine/prothrombin. Moreover, the induction of APC-R by aPL requires the presence of phospholipids and is suppressed by the presence of an excess of phospholipids. How phospholipids exposed on the cell membranes work in the system in vivo is unknown. Interestingly, acquired APC-R due to aPL might explain the clinical phenotypes of thrombotic APS. Indeed, the literature reports cases of both venous and arterial thromboembolism as well as skin necrosis, the latter observed in the severe form of protein C deficiency and in catastrophic APS.
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Affiliation(s)
- Vittorio Pengo
- Thrombosis Research Laboratory, University of Padova, Padova, Italy.,Arianna Foundation on Anticoagulation, Bologna, Italy
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Gemrnati D, Serino ML, Mari R, Verzola I, Moratelli S, Ballerini G. Different Anticoagulant Response to Activated Protein C (APC test) and to Agkistrodon Contortix Venom (ACV test) in a Family with FV-R506Q Substitution. Clin Appl Thromb Hemost 2016. [DOI: 10.1177/107602969700300304] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
To identify the defect(s) responsible for the thrombotic condition affecting a 55-year-old male and his family, we have utilized a new methodological approach (ProC Global®, Istituto Behring, Milan, Italy) to screen the global anticoagulant activity of the protein C pathway, a defect that accounts for the majority of inherited thrombophilias. The test is based on the activation of endogenous protein C in plasma by Protac®, derived from Agkistrodon contortix snake venom (ACV test). Nineteen members of the family were investigated, 11 showed low responsiveness to ACV (normalized ACV ratios < 0.66; normal > 1. 12); in these individuals specific assays of protein C (PC) and protein S (PS) levels and normalized activated protein C ratios (n-APC-r) were performed. A second test evaluating response to APC, using the classic commercial APC test (n-APC-r 1), detected only 10 subjects with abnormal responses : the propositus and two members of the family with n-APC-r 1 values < 0.54, indicating the homozygous state for the R506Q factor V gene mutation, and seven with values ranging 0.69-0.83, consistent with the heterozygous condition (normal > 0.85). Although only ten subjects presented with low n-APC-r 1 values, DNA analysis, in agreement with the ACV test, detected 11 individual with factor V-R506Q substitution (two homozygotes and nine heterozygotes). Thus the classical APC test failed to identify the APC resistance phenotype in two heterozygous subjects whose values were clearly normal (1.05) in the first case and homozygous (0.53) in the second. The ACV test, however, and the modified APC test with test plasma 1/5 diluted in factor V-deficient plasma (n-APC-r 2) completely matched the DNA analysis. A phenotype/genotype correlation was observed in dilutions higher than 1/3 test plasma factor V-deficient plasma. The presence of unknown mechanisms that influence plasma response to exogenous preformed APC (normal at high factor V-deficient plasma dilutions) but not endogenous ACV activated PC was suspected. The suspected low levels of proteins C and S found in several R506Q members of the family were excluded by reassaying the anticoagulant activities at higher plasma dilution ; this supports the known influence of factor V Leiden on functional PC and PS clotting activity. We conclude that the ACV test is appropriate to evaluate the APC resistance condition, but for a firm diagnosis DNA analysis together with the modified APC test are strongly advised even in the presence of unquestionable APC-r values. Key Words: APC resistance-Factor V Leiden-APC test-ACV test-Diagnosis-Inherited thrombophilia.
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Affiliation(s)
- Donate Gemrnati
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
| | - Maria L. Serino
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
| | - Rosella Mari
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
| | - Isabella Verzola
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
| | - Stefano Moratelli
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
| | - Giorgio Ballerini
- Center for the Study of Haemostasis and Thrombosis, University of Ferrara, Ferrara, Italy
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Parveen F, Shukla A, Agrawal S. Should factor V Leiden mutation and prothrombin gene polymorphism testing be done in women with recurrent miscarriage from North India? Arch Gynecol Obstet 2012; 287:375-81. [DOI: 10.1007/s00404-012-2557-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 09/06/2012] [Indexed: 11/28/2022]
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5
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Cai H, Hua B, Fan L, Wang Q, Wang S, Zhao Y. A novel mutation (g2172-->c) in the factor V gene in a Chinese family with hereditary activated protein C resistance. Thromb Res 2010; 125:545-8. [PMID: 20304467 DOI: 10.1016/j.thromres.2010.02.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 02/04/2010] [Accepted: 02/16/2010] [Indexed: 11/18/2022]
Abstract
BACKGROUND Activated protein C resistance (APC-R) was a major risk factor for venous thromboembolism(VTE) in Caucasians, and at least 90% of APC-R were associated with the point mutation of factor V (FV) gene (Arg506-->Gln, FV Leiden). However, this genetic defect was extremely rare in Asian population. OBJECTIVE To identify the genetic defect of FV in a Chinese family with APC-R associated with VTE. METHODS We describe a Chinese family with a history of venous thrombosis. Blood samples were obtained from five family members (including the proband) for screening APC-R by coagulation assay and the genetic defect of FV using direct sequencing. RESULTS Four out of five members had APC-R. We identified a novel mutation (G2172-->C) in exon 13 of the FV gene, which was present in all the individuals with APC-R but was absent in the individual without APC-R. This mutation is predicted to result in the replacement of glutamate by aspartate at position 666, close to one of the APC cleavage sites. CONCLUSIONS We have identified, for the first time, a novel mutation (G2172-->C) of FV that was associated with APC-R in a Chinese family with VTE. We speculate that this mutation interferes with cleavage at Arg679 by APC. The incomplete penetrance of thrombotic phenotype in this family, similar to that conferred by FV Leiden, suggests that it might be a weak risk factor for VTE.
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Affiliation(s)
- Huacong Cai
- Department of Hematology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100730, China
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Abstract
Inherited and acquired thrombophilias have been associated with recurrent pregnancy loss. Over recent years our ability to detect protein and genetic abnormalities responsible for thrombotic tendency has improved. We are now left with the task of deciphering which of these thrombophilias carries an increased risk for recurrent pregnancy loss. Acquired thrombophilias including lupus anticoagulant and anticardiolipin antibodies have been linked to recurrent pregnancy loss. However the evidence for the role of inherited thrombophilias such as, heterozygosity for the factor V Leiden, prothrombin G20210A mutation, the methylenetetrahydrofolate reductase (C677T MTHFR) mutation, as well as deficiencies of antithrombin, protein C and protein S is less clear. The methods for diagnosis and the evidence for their associations are discussed in this paper. Treatment modalities independent of those needed to prevent thrombotic events in pregnancy have generally not been studied. Given the present available data, there is insufficient evidence to include inherited thrombophilias in the initial evaluation of RPL. It is important to look for other, more common, causes of recurrent miscarriage in the evaluation of these patients.
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Affiliation(s)
- Amy M Adelberg
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, 214 MacNider, Chapel Hill, NC 27599-7516, USA
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Gemmati D, Serino ML, Tognazzo S, Ongaro A, Moratelli S, Gilli G, Forini E, De Mattei M, Scapoli GL. The reduced sensitivity of the ProC Global test in protein S deficient subjects reflects a reduction in the associated thrombotic risk. Blood Coagul Fibrinolysis 2001; 12:691-7. [PMID: 11734670 DOI: 10.1097/00001721-200112000-00011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
To investigate simultaneously a defect affecting the protein C/protein S (PC/PS) anticoagulant pathway is possible thanks to a methodological approach (ProC(R) Global; Dade Behring) based on the activation of endogenous plasma PC by a snake venom extract. Factor V (FV) Leiden, the most frequent cause of hereditary thrombosis, is well detected by the test with sensitivity of 100% irrespective of the presence/absence of thrombosis in the subjects investigated. The test is also suited to detect PC or PS defect, but in this case the in vitro impairment of the PC/PS pathway is less pronounced particularly for PS defects (sensitivity for PC and PS defect, 85-100 and 30-90%, respectively). In this study, we hypothesized that the lower sensitivity described for PS defect, compared with those of PC and FV Leiden defects, could also be related to the clinical condition of the subject investigated (symptomatic/asymptomatic) rather than solely to the PS plasma activity/level. Therefore, we analyzed 126 subjects with single congenital defects in the PC/PS pathway: 46 subjects with PS deficiency (26 thrombotic cases and 20 asymptomatic relatives), 40 subjects with PC deficiency (25 thrombotic cases and 15 asymptomatic relatives), and 40 heterozygous FV Leiden subjects (25 thrombotic cases and 15 asymptomatic relatives). By a cut-off of normalized Agkistrodon contortix snake venom ratio of 0.84, the sensitivity in the whole group of cases (sensitivity a) was 76.1, 95.0 and 100%, respectively, for PS, PC and FV Leiden defects. The test failed to detect 11 (23.9%) among the 46 PS-deficient subjects, and all these cases except two belonged to the asymptomatic subgroup (9/20; 45%). Excluding the 20 asymptomatic relatives, the new sensitivity (sensitivity b) for the PS defect was 92.3%. The comparison of the sensitivity in the symptomatic PS cases and in the asymptomatic ones was significantly different (P = 0.010). Among the 40 PC-deficient subjects, only two (5.0%) were not detected by the test and they belonged indifferently to the two subgroups. Finally, none of the 40 FV Leiden heterozygotes were misdiagnosed by the test. These results suggest that in symptomatic PS-deficient cases the test could reflect a post-thrombotic effect and/or reveal potential unidentified prothrombotic influences assessing a prothrombotic risk condition.
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Affiliation(s)
- D Gemmati
- Centre for the Study of Haemostasis and Thrombosis, University of Ferrara, Italy.
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8
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Affiliation(s)
- P Clark
- Department of Transfusion Medicine, Ninewells Hospital and Medical School, Dundee, Scotland, UK
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Merrill JT. Clinical trials for the antiphospholipid syndrome. Curr Rheumatol Rep 2000; 2:233-7. [PMID: 11123064 DOI: 10.1007/s11926-000-0084-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- J T Merrill
- Division of Rheumatology, Department of Medicine, St. Lukes-Roosevelt Hospital Center, 432 West 58th Street, New York, NY 10019, USA
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Fernández JA, Kojima K, Petäjä J, Hackeng TM, Griffin JH. Cardiolipin enhances protein C pathway anticoagulant activity. Blood Cells Mol Dis 2000; 26:115-23. [PMID: 10753602 DOI: 10.1006/bcmd.2000.0285] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The anticoagulant activity of activated protein C (APC) was studied using factor Xa-1-stage assays of both the procoagulant and anticoagulant activities of phospholipid vesicles containing phosphatidylserine or cardiolipin as active phospholipids. In the absence of APC, phosphatidylserine vesicles showed higher procoagulant activity than cardiolipin vesicles whereas cardiolipin vesicles supported APC-dependent anticoagulant activity better than phosphatidylserine vesicles. Enhancement of APC anticoagulant activity in plasma by cardiolipin was markedly stimulated by the APC cofactor protein S. In purified reaction mixtures, cardiolipin in phospholipid vesicles dose-dependently enhanced APC anticoagulant activity. This effect of cardiolipin was partially dependent on protein S, and immunoblotting studies showed that cardiolipin enhanced the APC-mediated cleavage of the factor Va heavy chain at Arg506 and Arg306. In solid-phase binding assays, increasing amounts of cardiolipin in multicomponent phospholipid vesicles increased the affinity for protein S and to a lesser extent APC. These data are consistent with the hypothesis that cardiolipin stimulates the anticoagulant protein C pathway by increasing the affinity of phospholipid surfaces for protein S:APC and by enhancing inactivation of factor Va by APC due to cleavages at Arg506 and Arg306 in factor Va. Based on this, it is further hypothesized that anti-cardiolipin or anti-oxidized cardiolipin antibodies may be thrombogenic because they inhibit phospholipid-dependent expression of the anticoagulant protein C pathway.
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Affiliation(s)
- J A Fernández
- Department of Molecular and Experimental Medicine, Scripps Research Institute, La Jolla, California 92037, USA
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11
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Abstract
Activated protein C resistance (APCR) in the absence of alterations in the factor V gene has been observed during pregnancy, in patients on oral contraceptives, in the presence of antiphospholipid antibodies, and in patients with ischemic stroke. We report a 49-year-old woman with recurrent major venous and arterial thromboses who displayed pronounced APCR, yet no changes in the activated protein C (APC) cleavage sites of factor V. The APCR values determined by four different assays were similar to those obtained in plasma from a homozygote for factor V Q506. Addition of IgG isolated from the patient’s serum to normal plasma lowered the APCR ratio from 2.4 to 1.6. Incubation of patient’s IgG with normal APC resulted in a profound change in the mobility of APC in crossed immunoelectrophoresis. APC was also shown to bind to patient’s IgG immobilized on a protein A agarose column. Factor Va inactivation by APC was inhibited by patient’s IgG, but not by control IgG in the presence or absence of either phospholipids or protein S. These results provide evidence for the existence of an acquired antibody against APC in the patient’s plasma, which gave rise to the APCR phenotype and was probably responsible for the major thrombotic events. We suggest that acquired APCR due to anti-APC antibodies be considered a potential cause for severe venous and arterial thromboses.
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12
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Roubey RAS. The Antiphospholipid Syndrome. Lupus 1999. [DOI: 10.1007/978-1-59259-703-1_29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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13
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Gemmati D, Serino ML, Scapoli GL. A modified functional global test to measure protein C, protein S activities and the activated protein C-resistance phenotype. Thromb Res 1998; 92:141-8. [PMID: 9806366 DOI: 10.1016/s0049-3848(98)00120-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Identifying a defect affecting the protein C/protein S (PC/PS) anticoagulant system, using a single global test, has recently become possible thanks to a new methodological approach based on the activation of endogenous plasma PC by Protac, derived from Agkistrodon Contortix snake venom (ACV). The introduction of a commercial test (ProC Global), ACV-based, provides a useful tool for the screening of thrombotic patients since the most frequent causes of inherited thrombophilia are found in the PC/PS system. The test provides information only on the global activity of the anticoagulant pathway but not on PC and PS activity or on the factor V related conditions (e.g., FV Leiden). The present study shows that by carrying out the test alternating the presence of PC-, PS-, or FV-deficient plasma and using appropriate amounts of ACV, it is possible to increase the specificity of the test to correctly evaluate respectively the PC or PS activities or the activated protein C resistance condition (APC-R). These simple modifications applied to the original commercial test allow to detect exactly, using a single, basic methodology, the principal defects affecting the PC/PS anticoagulant pathway. Furthermore, carrying out the tests on an automated coagulometer, in combination or not with the classic ProC Global assay, it is possible to use a unique reagent profile to simultaneously investigate in the same or different samples, the PC, PS, and APC-R defect.
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Affiliation(s)
- D Gemmati
- Centre for the Study of Haemostasis and Thrombosis, University of Ferrara, Italy
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Nakamura N, Ban T, Yamaji K, Yoneda Y, Wada Y. Localization of the apoptosis-inducing activity of lupus anticoagulant in an annexin V-binding antibody subset. J Clin Invest 1998; 101:1951-9. [PMID: 9576760 PMCID: PMC508782 DOI: 10.1172/jci119889] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Lupus anticoagulant (LAC) is associated with arterial and venous thrombosis, thrombocytopenia, and recurrent fetal loss. We have reported previously that plasma with LAC activity induces apoptosis in endothelial cells and binds annexin V (Nakamura, N., Y. Shidara, N. Kawaguchi, C. Azuma, N. Mitsuda, S. Onishi, K. Yamaji, and Y. Wada. 1994. Biochem. Biophys. Res. Commun. 205:1488-1493). In this study, we separated two IgG antibody fractions, one with and one without affinity for annexin V, from 10 patients with LAC. LAC and apoptotic activities were localized in the annexin V-binding fraction in all 10 patients. DNA fragmentation was dose-dependent, paralleling the amount of IgG added to the human umbilical vein endothelial cell culture medium, and was inhibited by preincubation with annexin V. Removal of the antiphospholipid antibodies from patient IgG with phospholipid liposomes did not abolish the apoptosis-inducing activities or binding to annexin V. These results imply that patients with LAC often have antibodies that do not bind phospholipids and are responsible for the induction of apoptosis in endothelial cells.
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Affiliation(s)
- N Nakamura
- Department of Molecular Medicine, Research Institute, Osaka Medical Center for Maternal and Child Health, Izumi, Osaka 590-02, Japan
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Haruta K, Kobayashi S, Hirose S, Horiai A, Ohyanagi M, Tanaka M, Kawano T, Shirai T, Takasaki Y, Hashimoto H. Monoclonal Anti-Cardiolipin Antibodies from New Zealand Black × New Zealand White F1 Mice React to Thrombomodulin. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.1.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
The reactivity with and affinity for thrombomodulin (TM) of monoclonal anti-cardiolipin Abs (MoaCL), derived from a New Zealand Black × New Zealand White F1 (NZB/W F1) mouse, were studied to investigate the pathogenicity of anti-cardiolipin Abs (aCL). Four of eighteen MoaCL were found to react with rabbit TM when examined using ELISA. These four MoaCL also reacted with synthetic peptide that included the epidermal growth factor-like domain of human TM, a binding site for thrombin. The reaction with TM of these four MoaCL was inhibited by bovine thrombin. When the affinity for TM of the MoaCL was determined, the dissociation constants (Kd) ranged from 4.8 × 10−9 to 4.7 × 10−8 M. By contrast, examination of the affinity for cardiolipin (CL) gave values from 8.3 × 10−6 to 7.4 × 10−5 M. Thus, these MoaCL reacted to TM with a higher affinity than to CL. Moreover, these MoaCL also bound to TM on HUVEC and down-regulated the expression level of TM on the surface of HUVEC due to internalization of TM. The binding of thrombin to TM is known to initiate rapid protein C activation, and complexes of activated protein C and protein S show anticoagulatory activity. Thus, the present studies suggest that certain pathogenic aCL cross-react with TM and induce down-regulation of TM on endothelial cells, followed by induction of thrombosis.
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Affiliation(s)
- Kazuhiko Haruta
- *Research Laboratory, Zenyaku Kogyo Co. Ltd., and Departments of
- †Rheumatology and Internal Medicine and
| | | | - Sachiko Hirose
- ‡Pathology, Juntendo University School of Medicine, Tokyo, Japan
| | | | | | | | | | - Toshikazu Shirai
- ‡Pathology, Juntendo University School of Medicine, Tokyo, Japan
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Dizon-Townson DS, Kinney S, Branch DW, Ward K. The factor V Leiden mutation is not a common cause of recurrent miscarriage. J Reprod Immunol 1997; 34:217-23. [PMID: 9350638 DOI: 10.1016/s0165-0378(97)00039-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Some investigators suggest that placental thrombosis and infarction can cause recurrent miscarriage. We have shown that the common missense mutation in the factor V gene, the Leiden mutation, which renders factor Va resistant to cleavage inactivation by activated protein C, predisposes to placental thrombosis and spontaneous miscarriage. Our objective was to determine the frequency of the Leiden mutation in a population with well-characterized idiopathic recurrent miscarriage. DNA was extracted from whole blood of 40 couples with a history of idiopathic recurrent miscarriage and 25 couples with a history of proven fertility (seven or more live births). The polymerase chain reaction was used to amplify exon 10 of the factor V gene followed by allele-specific restriction with Mnl1 for mutation detection. Results were analyzed with a chi 2 contingency table. None of the 40 women with idiopathic recurrent miscarriage carried the mutation and only one of their reproductive partners was heterozygous for the mutation. Similarly, none of the control women carried the mutation, and only one of the 25 control male partners was heterozygous for the mutation. In our referral population, the factor V Leiden mutation which predisposes to thrombosis is not a common cause of recurrent miscarriage.
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Affiliation(s)
- D S Dizon-Townson
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City 84132, USA.
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17
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Nowak-Göttl U, Auberger K, Göbel U, Kreuz W, Schneppenheim R, Vielhaber H, Zenz W, Zieger B. Inherited defects of the protein C anticoagulant system in childhood thrombo-embolism. Eur J Pediatr 1996; 155:921-7. [PMID: 8911889 DOI: 10.1007/bf02282879] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Childhood thrombo-embolism is mostly the result of inherited thrombophilia or vascular insults combined with risk factors such as peripartal asphyxia, fetopathia diabetica, exsiccosis, septicaemia, central lines, congenital heart disease, cancer, trauma, surgery or elevated antiphospholipid antibodies. Inherited thrombophilia includes mainly defects of the protein C pathway, resistance to activated protein C, protein C or protein S deficiency. Resistance to activated protein C, in the majority of cases caused by the point mutation Arg 506 Gln of the factor V gene, has emerged as the most important hereditary cause of thrombo-embolism in adults and children. However, since an acquired risk of thrombo-embolic complications frequently masks the inherited deficiency in affected children, children with thrombo-embolism should have adequate laboratory evaluation for inherited coagulation disorders, especially the protein C pathway. Until more data on childhood thrombo-embolism are available, treatment recommendations will continue to be extrapolated from guidelines for adults.
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Affiliation(s)
- U Nowak-Göttl
- Westfälische Wilhelms-Universität, Department of Paediatrics, Paediatric Haematology and Oncology, Münster, Germany
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18
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de Groot PG, Horbach DA, Derksen RH. Protein C and other cofactors involved in the binding of antiphospholipid antibodies: relation to the pathogenesis of thrombosis. Lupus 1996; 5:488-93. [PMID: 8902788 DOI: 10.1177/096120339600500532] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In this review we will discuss the possible interference of antiphospholipid antibodies with the protein C system. Antiphospholipid antibodies can interfere with the protein C system in different ways: (i) via inhibiting the formation of thrombin; (ii) via interference with the activation of protein C by the thrombomodulin-thrombin complex; (iii) via inhibition of the assembly of the protein C complex; (iv) via inhibition of the activity of protein C, directly or via its cofactor protein S, and (v) via antibodies directed against the substrates of APC, factors Va and VIIIa, thereby protecting them for inactivation. The experimental and theoretical indications that one of these mechanisms will explain the pathogenesis of the antiphospholipid syndrome is critically examined.
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Affiliation(s)
- P G de Groot
- Department of Haematology, University Hospital Utrecht, The Netherlands
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Roubey RA. Immunology of the antiphospholipid antibody syndrome. ARTHRITIS AND RHEUMATISM 1996; 39:1444-54. [PMID: 8814055 DOI: 10.1002/art.1780390903] [Citation(s) in RCA: 227] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- R A Roubey
- Division of Rheumatology and Immunology, University of North Carolina, Chapel Hill 27599-7280, USA
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20
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Nowak-Göttl U, Vielhaber H, Schneppenheim R, Koch H. Coagulation and fibrinolysis in children with APC-resistance: a population study. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0268-9499(96)80040-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Nowak-Göttl U, Kohlhase B, Vielhaber H, Aschka I, Schneppenheim R, Jürgens H. APC resistance in neonates and infants: adjustment of the APTT-based method. Thromb Res 1996; 81:665-70. [PMID: 8868517 DOI: 10.1016/0049-3848(96)00043-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Resistance to activated protein C (APCR) has emerged as the most important hereditary cause of venous thromboembolism. Using an aPTT-based method together with DNA technique we investigated 120 healthy neonates and infants < 12 months of age and 24 infants with septicaemia for the presence of this mutation. In addition, data of 11 neonates with vascular occlusion, heterozygous (+/-) for the Arg 506 Gln mutation were included. Results of an aPTT-based method (clotting time using the APC/CaCl2 solution obtained in an undiluted, 1:5 and 1:11 dilution with factor V deficient plasma divided by clotting time with CaCl2 in the same plasma dilution) are shown: Whereas 7 (5.5%) out of 120 healthy neonates were (+/-) carriers for the factor V Arg 506 Gln mutation, concordance with the aPTT-based method (cut-off defined as ratio < 2) was found only when using the 1:11 plasma dilution. Six (four) out of 24 infants with sepsis, not carrying the factor V mutation, would have been classified as APC resistant when using the 1:1 (1:5) plasma dilution. Four (two) out of 18 patients, (+/-) for the Arg 506 Gln mutation showed APC ratios > 2 in the 1:1(1:5) plasma dilution.
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Affiliation(s)
- U Nowak-Göttl
- Department of Paediatrics, University Hospital Kiel, Germany
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22
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Merrill JT, Lahita RG. The antiphospholipid syndrome and SLE: is there a clue in the link between complement and coagulation? Lupus 1996; 5:6-10. [PMID: 8646228 DOI: 10.1177/096120339600500103] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The heterogenous immunoglobulins known as antiphospholipid antibodies (APLA) or lupus "anticoagulants" (LA) are prevalent in lupus patients and have been implicated in life-threatening thromboembolic events. Unfortunately, observing the presence of these antibodies in an individual does not predict the likelihood of an event nor does it predict when it may occur. A pathogenic role for these antibodies is supported by the observation that high titers and IgG isotype confer an increased risk of thromboembolism. Additionally, numerous reports indicate that isolated patient antibodies interfere with various elements of the coagulation cascade. Nevertheless, attempts to correlate specific antibody characteristics with the future likelihood of a hypercoagulable event in an individual patient have been unsuccessful to date. Given such uncertainty combined with the potential complications of anticoagulant medications, patients are generally not treated until significant morbidity has occurred. Finally, because of the apparent high rate of reoccurrence most patients must remain on anticoagulant therapy indefinitely, regardless of need.
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Affiliation(s)
- J T Merrill
- Division of Rheumatology and Connective Tissue Diseases, St. Luke's/Roosevelt Hospital Center, New York, NY 10019, USA
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23
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Abstract
The pathogenesis of the antiphospholipid syndrome remains uncertain. Antibodies that react with phospholipids may not be directly responsible for cellular injury, but may be part of the immune network through which autoantibodies with pathogenic potential are generated. The latter may recognize proteins such as beta 2-glycoprotein I that form complexes with phospholipids, proteins whose functions depend upon interaction with phospholipids such as protein C and its cofactors, altered lipoproteins such as oxidized low-density lipoproteins, or other molecules that share only antigenic similarity. Thus, a spectrum of autoantibodies that recognize different lipid-protein complexes may develop in these patients and contribute to the observed clinical heterogeneity of the syndrome. Current techniques do not permit identification of the subset of patients with antiphospholipid antibodies at risk for thrombosis or abortion and there are no prospective, controlled trials addressing the prophylaxis or treatment of affected individuals. Identification of the cellular targets of antibodies to lipid-protein moieties is needed to identify patients at risk for these complications and as a means to monitor therapy.
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Affiliation(s)
- D B Cines
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia 19104, USA
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24
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Kraus M, Zander N, Fickenscher K. Coagulation assay with improved specificity to factor V mutants insensitive to activated protein C. Thromb Res 1995; 80:255-64. [PMID: 8578552 DOI: 10.1016/0049-3848(95)00174-p] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The prevalence of a new hereditary defect in the protein C anticoagulant pathway, the factor V-Leiden, has been reported to range between 20% to 60% in familial thrombophilia. In addition to differences in patient groups, these very divergent numbers might also be due to the detection method applied. In most studies a modified APTT was used, where activated protein C (APC) is added simultaneously with the start of the clotting reaction. However, this method is also influenced by other factors like protein S, factor VIII or lupus anticoagulants. Furthermore, heparin or oral anticoagulant therapy might interfere. We tried to develop a coagulation assay dependent only on those mutant forms of factor V stable against proteolytic attack by APC. For this purpose, samples were first diluted with a factor V deficient plasma (f.V-dp). Then, coagulation was initiated either on the intrinsic pathway (APTT) or on the extrinsic pathway (PT) or, by directly activating factor X (RVVT). Additionally, APC was added, which prolongation of the clotting time. Deficiencies in protein S or the presence of factor V-Leiden resulted in a less pronounced clotting time prolongation. Titration of protein S-deficient plasma samples with f.V-dp diminished this effect. In contrast, in samples with factor V-Leiden the difference to the clotting time obtained with normal plasma even increased in the order APTT>>RVVT>PT. In the APTT-based method high concentrations of factor VIII shortened the clotting times, thus mimicking a factor V-Leiden defect. This could be compensated for up to 4 U/ml factor VIII by using a f.V-dp containing factor VIII at physiological concentration. Neither unfractionated nor LMW-heparin (up to 2 U/ml) interfered with the determination. In a brief investigation on 16 plasma samples from patients under oral anticoagulation 5 (30%) showed a similar behaviour as observed with normal plasma from factor V-Leiden carriers. These results let us suggest that by simply mixing the patient sample with a factor V-deficient plasma factor V-Leiden might be detected also in patients under oral anticoagulant therapy. Inherited disorders of protein C or protein S are well known as thrombotic risk factors (1). The recent investigations by Dahlbäck et al. (2) led to the discovery of a new hereditary defect in the protein C anticoagulant pathway: the factor V-Leiden (3). This mutation renders activated factor V stable against proteolytic attack by activated protein C (APC). The reports on the prevalence of this mutation in thrombophilic patients show a considerable variation between 21% (4) and 64% (5).(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- M Kraus
- Research Laboratories of Behringwerke AG, Marburg, Germany
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25
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Váradi K, Moritz B, Lang H, Bauer K, Preston E, Peake I, Rivard GE, Keil B, Schwarz HP. A chromogenic assay for activated protein C resistance. Br J Haematol 1995; 90:884-91. [PMID: 7669667 DOI: 10.1111/j.1365-2141.1995.tb05210.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Resistance to activated protein C (APC) diagnosed on the basis of prolongation of clotting time in an activated partial thromboplastin time (aPTT) assay is now considered a major cause of inherited thrombophilia. The majority of patients with APC resistance carry a factor V molecule with a point mutation at one APC cleavage site (Arg506Gln) which prevents the optimal inactivation of activated factor V by APC. To overcome the limitations of aPTT-based assays in the diagnosis of APC resistance, we have developed a chromogenic assay which is based on the capacity of APC to limit the generation of factor Xa by inactivating factor VIIIa in plasma. The ratio of the factor Xa amidolytic activity in a sample without APC to its factor Xa activity with the addition of APC reflects the response of the plasma coagulation system to APC. The normal range in 44 healthy individuals was 1.62-2.06. APC response ratios as measured by the chromogenic assay correlated with ratios measured by the aPTT assay and were below the normal range in 23/24 individuals with Arg506Gln mutant factor V from three different families with familial thrombosis and from 11 unrelated asymptomatic individuals. In reconstitution experiments, purified factor V corrected the decreased APC response in plasma samples from patients with the Arg506Gln mutation as well as with factor V deficiency, and increased the APC response in normal plasma, whereas the addition of activated factor V had no enhancing effect.
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Affiliation(s)
- K Váradi
- Research Laboratories of Immuno AG, Vienna, Austria
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26
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Kraus M, Noah M, Fickenscher K. The PCAT--a simple screening assay for assessing the functionality of the protein C anticoagulant pathway. Thromb Res 1995; 79:217-22. [PMID: 7676408 DOI: 10.1016/0049-3848(95)91525-p] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- M Kraus
- Research Laboratories of Behringwerke AG, Marburg, Germany
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27
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Bokarewa MI, Bremme K, Falk G, Sten-Linder M, Egberg N, Blombäck M. Studies on phospholipid antibodies, APC-resistance and associated mutation in the coagulation factor V gene. Thromb Res 1995; 78:193-200. [PMID: 7631299 DOI: 10.1016/0049-3848(95)00048-v] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The influence of antibodies against phospholipids (PLa) on APC response was investigated in 155 women with a history of thromboembolism and/or repeated foetal losses. PLa were determined as antibodies against cardiolipin (CLa) and phosphatidyl serine (PSa) and as lupus anticoagulant (LA) tested by dilute Russell's Viper Venom time and by the Textarin/Ecarin ratio. APC-response was studied by a clotting (aPTT-based) and by an amidolytic (factor IXa-X-based) assay. A reduced response to APC (APC-resistance) was found in 49% of 65 PLa-positive and in 13% of 90 PLa-negative samples (chi 2 = 23.9; p < 0.5 x 10(-4)). It was more common in the samples with LA, as compared to CLa+PSa positive (58% vs. 30%, not significant). The presence of the mutation causing Arg506-Gln substitution in coagulation factor V was investigated in 84 samples. The occurrence of the mutation in APC-resistant patients with CLa+PSa or with LA in one of the two assays was similar to those without PLa (84% and 100%, respectively). In the absence of APC resistance, the occurrence of the mutation was similar in the samples with and without PLa (14% vs. 11%). Samples with LA, determined by both tests used, comprised a special group where the frequency of the mutation in the APC resistant samples was significantly reduced (p < 0.01). In the latter samples, the pathogenic mechanism of APC resistance may be connected with the influence on phospholipid membranes.
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Affiliation(s)
- M I Bokarewa
- Department of Laboratory Medicine/Blood Coagulation Research, Karolinska Institute, Stockholm, Sweden
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28
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Kraus M, Wagner C. Evaluation of APC-sensitivity in normal blood donors using different reagents and instruments. Thromb Res 1994; 76:231-6. [PMID: 7863473 DOI: 10.1016/0049-3848(94)90194-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- M Kraus
- Research Laboratories of Behringwerke AG, Marburg, Germany
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29
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Vasse M, Leduc O, Borg JY, Chrétien MH, Monconduit M. Resistance to activated protein C: evaluation of three functional assays. Thromb Res 1994; 76:47-59. [PMID: 7817360 DOI: 10.1016/0049-3848(94)90206-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Resistance to Activated Protein C (APC) was evaluated using 3 different methods: two of them were based on the prolongation of the Activated Partial Thromboplastin Time (APTT) using 2 different APTT reagents in the presence of APC, whereas the third method was based on the prolongation of prothrombin time when APC is added. The three methods were significantly correlated. APTT-based assays were sensitive to factor XII deficiency, whereas thromboplastin-based assay was sensitive to factor VII deficiency (< 0.5 UI/ml), which surestimates the response to APC. In contrast, an increase in factor VIII (F. VIII) level is associated with a decreased response to APC, when APTT-based assays are used, whereas thromboplastin-based assay is unmodified. During pregnancy, a decreased response to APC is observed, which is not only due to the increase in F. VIII, since thromboplastin-based assay is also modified. In Protein S (PS) immuno-depleted plasma, the low response to APC is corrected by addition of free PS: the thromboplastin-based assay was the most sensitive one to PS deficiency. However, in patients with congenital PS deficiency, there was no correlation between APC-resistance and free PS level. In patients with lupus anticoagulant, discrepancies were observed between the 3 methods, but with a high frequency of low response to APC. For the 3 assays, there was a good differentiation and correlation between normal and pathological results, the thromboplastin-based assay being perhaps the most discriminating. However, 3 unrelated thrombophilic patients showed normal results using thromboplastin-based assay, although they were APC-resistant using APTT-based assays. For 2 patients, this discrepancy can be explained by high levels of F. VIII. For the last patient, an abnormal F. VIII, resistant to APC can be suspected.
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Affiliation(s)
- M Vasse
- Hôpital Charles Nicolle, Rouen, France
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30
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Tohgi H, Takahashi H, Kashiwaya M, Watanabe K, Hayama K. The anticardiolipin antibody in elderly stroke patients: its effects on stroke types, recurrence, and the coagulation-fibrinolysis system. Acta Neurol Scand 1994; 90:86-90. [PMID: 7801744 DOI: 10.1111/j.1600-0404.1994.tb02685.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Anticardiolipin antibody (aCL) is known as a risk marker for stroke, particularly in subjects younger than 50 years of age. We studied the effects of aCL on stroke types, recurrences, and the coagulation-fibrinolysis system in 257 elderly patients (63.2 +/- 11.4 years). Follow-up was performed for 3.1 years on 184 patients, for whom the rate of symptomatic and asymptomatic reinfarcts on CT was studied. aCL was positive in 30 (12%) of the patients. The incidence of atherosclerotic changes in the cerebral arteries was not significantly different between aCL-positive and aCL-negative patients. The aCL-positive patients had a greater rate of individuals not having any of the known risk factors (p < 0.05), a greater incidence of cortical infarctions (p < 0.05), more frequent symptomatic recurrences (p < 0.05). They had significantly greater changes in molecular markers for the coagulation-fibrinolysis system in the acute phase (p < 0.05), but not in the chronic phase.
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Affiliation(s)
- H Tohgi
- Department of Neurology, Iwate Medical University, Tokyo, Japan
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31
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Affiliation(s)
- P G de Groot
- Department of Haematology, University Hospital Utrecht, The Netherlands
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32
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Abstract
Haematological involvement is common in systemic lupus erythematosus (SLE). Whilst anaemia is most often due to chronic disease, other causes such as autoimmune haemolytic anaemia and hypoplastic anaemia need to be considered. The increased risk of infection in patients with SLE is due in part to changes in the white blood cells though treatments do not yet aim to modify these. Thrombocytopenia occurs frequently and is almost invariably autoimmune. It is often of little consequence, but may occasionally be severe and serious, requiring aggressive treatment. Patients with SLE have an increased risk of thrombosis, increased further in the presence of antiphospholipid antibodies (aPL). Changes in the haemostatic system and new insights into the nature of aPL are described.
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Affiliation(s)
- D M Keeling
- Department of Haematology, Addenbrooke's Hospital, Cambridge, UK
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33
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Abstract
Despite important new diagnostic laboratory and imaging technologies, the cause of brain infarction remains unexplained in 20% to 40% of subjects. Most stroke patients do not require extensive evaluations of coagulation, but hypercoagulability may account for a significant proportion of unexplained strokes. Hemostatic abnormalities associated with stroke may be broadly classified as familial or acquired. Principal among the familial thrombotic coagulopathies are deficiencies in concentration or function in protein-C, protein-S, and antithrombin III, but other hereditary abnormalities include sickle cell disease, homocystinuria, and dysfibrinogenemia. The acquired disorders of hemostasis associated with stroke probably constitute a larger proportion of the important stroke-related coagulopathies. In particular, the aPL antibody syndrome is now strongly associated with thrombotic events including stroke, although neither the mechanism of thrombosis nor effective therapies for this syndrome have been clearly elucidated. Many of the acquired hemostatic abnormalities exist within a special clinical setting such as with malignancy or with myeloproliferative diseases, nephrotic syndrome, and liver disease. Presumably many of these share common pathways of coagulation activation or dysfunction with the inherited disorders. Most of the hemostatic disorders in stroke are associated with dysfunction of vascular endothelium and abnormalities of or interference with the natural anticoagulant proteins: protein-C, protein-S, and antithrombin III. Improved understanding of these relationships should lead to better diagnosis and treatment for people at risk of stroke.
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Affiliation(s)
- B M Coull
- Department of Neurology, Oregon Health Sciences University, Portland 97201
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34
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Grunebaum L, Kheiralla JC, Wiesel ML, Freyssinet JM, Goetz J, Imler M, Cazenave JP. [Antiphospholipid antibodies (aPL): detection and clinical significance]. Rev Med Interne 1992; 13:307-14. [PMID: 1287776 DOI: 10.1016/s0248-8663(05)80309-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Phospholipid-binding antibodies are heterogeneous immunoglobulins of G and/or M and/or A class which can be detected in association with a variety of pathologies. However they can also occur in the absence of any clinical manifestations. Despite their paradoxical in vitro anticoagulant activity, phospholipid-binding antibodies, either primary or secondary, are frequently associated with venous and/or arterial thrombotic events. Hence, their detection has to be performed in several major clinical situations, cerebral attack, myocardial infarction, recurrent fetal loss, deep vein thrombosis ... Their course has to be controlled at least every six months. Since the incidence of phospholipid-binding antibodies in auto-immune pathologies is high, immunological disorders should also be considered. As yet there is no standardized assay of phospholipid-binding antibodies, either functional with respect to their anticoagulant activity, or immunological (ELISA). It is not established whether they possess an own pathogenic potential or appear as a secondary response following cellular alterations known to be thrombogenic. However it has been suggested that they could participate in the disruption of the hemostatic balance towards procoagulant tendency resulting in thrombosis.
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Affiliation(s)
- L Grunebaum
- Service d'Hémostase et de Thrombose, Centre Régional de Transfusion Sanguine, INSERM U 311, Strasbourg
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35
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36
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Stankiewicz AJ, Crowley JP, Steiner M. Increased levels of tissue plasminogen activator with a low plasminogen activator inhibitor-1 in a patient with postoperative bleeding. Am J Hematol 1991; 38:226-9. [PMID: 1951323 DOI: 10.1002/ajh.2830380314] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Recurrent postoperative bleeding in a previously healthy man with a moderate prolongation of PT and PTT which did not correct with vigorous fresh-frozen plasma infusion was identified as a unique abnormality of the fibrinolytic system: a combination of an excess of tissue plasminogen activator (t-PA) at 300% of normal activity accompanied by a concurrent deficiency of plasminogen activator inhibitor-1 activity (PAI-1) of 10-20% of normal activity. This observation underscores the potentially important regulatory role of PAI-1 in the degree to which clinical manifestations of bleeding tendencies may occur in patients in whom an excess amount of t-PA is expressed.
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Affiliation(s)
- A J Stankiewicz
- Brown University Program in Medicine, Rhode Island Hospital, Providence 02903
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37
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Abstract
The central nervous system (CNS) is clinically involved in approximately 40% of all systemic lupus erythematosis (SLE) patients. Minor psychiatric symptoms and abnormalities on neuropsychological testing are being detected with increasing frequency. This review summarizes current thinking concerning the diagnosis and pathogenesis of CNS lupus. The main symptoms of CNS lupus can be diffuse (generalized seizures, psychosis) or focal (stroke, peripheral neuropathies). Neuropsychiatric symptoms often occur in the first year of SLE, but are rarely the presenting symptoms of the disease. In studies on the pathology of CNS lupus, vasculopathy, infarcts and haemorrhages are often observed, whereas vasculitis is rare. Endocardial lesions and mural thrombi have also been reported in 33-50% of CNS lupus patients. In diagnostic imaging of the CNS, magnetic resonance imaging (MRI) scans often provide evidence for edema or small infarcts, both in focal and diffuse CNS lupus, whereas computerized tomography (CT) scans only show gross abnormalities. The first reports on position emission tomography (PET) scans in CNS lupus patients show decreased glucose uptake in the brain. The cerebral blood flow decreases during active diffuse and focal CNS lupus. The blood-brain barrier is somewhat more frequently impaired in diffuse CNS lupus. Intrathecal IgG and IgM production is observed in 25-66% of all CNS lupus patient. Various specificities of autoantibodies have been observed in CNS lupus. Of these, anticardiolipin (ACA) antibodies show a well-documented association with focal involvement of the CNS in SLE. These antibodies could cause thrombosis by interfering with the protein C pathway of fibrinolysis. In addition, they are associated with endocardial and valvular heart disease, which is often observed in SLE and which could cause embolism. The relation between ACA and diffuse CNS lupus is not yet clear. Low-avidity anti-DNA antibodies are also found in CNS lupus, possibly because of their cross-reaction with cardiolipin. Antineuronal antibodies and lymphocytotoxic antibodies have been associated with diffuse CNS lupus and abnormalities on neuropsychological testing. However, the population of these antibodies is rather heterogeneous and it has not been possible to assess a common target antigen. Therefore, it is still obscure whether there is also a second immune-mediated mechanism responsible for the development of the diffuse form of CNS lupus.
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Affiliation(s)
- A P van Dam
- Central Laboratory of the Red Cross Blood Transfusion Service, Department of Autoimmune Diseases, Amsterdam, The Netherlands
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38
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Keeling DM, Campbell SJ, Mackie IJ, Machin SJ, Isenberg DA. The fibrinolytic response to venous occlusion and the natural anticoagulants in patients with antiphospholipid antibodies both with and without systemic lupus erythematosus. Br J Haematol 1991; 77:354-9. [PMID: 1707291 DOI: 10.1111/j.1365-2141.1991.tb08583.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Patients with systemic lupus erythematosus (SLE) have an increased risk of thrombosis and this is increased in the presence of antiphospholipid antibodies (APA). These APA are also associated with thrombosis in patients who do not have SLE. We compared haemostatic parameters in SLE patients with and without APA, and also compared patients who had APA but not SLE with healthy normal controls. No relationships between the natural anticoagulants, antithrombin III, heparin cofactor II, protein C and protein S, and the presence of APA were found. In the patients with SLE both tissue plasminogen activator antigen and plasminogen activator inhibitor (PAI) were increased, but these changes were not due to APA which had no effect on fibrinolysis in these patients. In the patients with APA who did not have SLE the fibrinolytic response to venous occlusion was reduced due to raised levels of PAI; similar changes have, however, been reported in some patients with idiopathic thrombosis.
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Affiliation(s)
- D M Keeling
- Department of Haematology, University College and Middlesex School of Medicine, London
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