Pathophysiological insights into the antiphospholipid syndrome

2017 ◽  
Vol 37 (03) ◽  
pp. 202-207 ◽  
Author(s):  
Davit Manukyan ◽  
Nadine Müller-Calleja ◽  
Karl Lackner

SummaryThe antiphospholipid syndrome (APS) is characterized by venous and/or arterial thrombosis and severe pregnancy morbidity in presence of antiphospholipid antibodies (aPL). While there is compelling evidence that aPL cause the clinical manifestations of APS, the underlying mechanisms are still a matter of scientific debate. This is mainly related to the broad heterogeneity of aPL. There are three major types of aPL: The first one binds to (anionic) phospholipids, e.g. cardiolipin, in absence of other factors (cofactor independent aPL). The second type binds to phospholipids only in presence of protein cofactors, e.g. ß2-glycoprotein I (ß2GPI) (cofactor dependent aPL). The third type binds to cofactor proteins directly without need for phospholipids. It is widely believed that cofactor independent aPL (type 1) are associated with infections and, more importantly, non-pathogenic, while pathogenic aPL belong to the second and in particular to the third type. This view, in particular with regard to type 1 aPL, has not been undisputed and novel research data have shown that it is in fact untenable. We summarize the available data on the pathogenetic role of aPL and the implications for diagnosis of APS and future research.

2020 ◽  
Vol 120 (11) ◽  
pp. 1557-1568
Author(s):  
Walid Chayoua ◽  
Dong-mei Yin ◽  
Hilde Kelchtermans ◽  
Gary W. Moore ◽  
Jean-Christophe Gris ◽  
...  

Abstract Background Anticardiolipin (aCL) and anti-β2 glycoprotein I (aβ2GPI) immunoglobulin A (IgA) antiphospholipid antibodies (aPL) have shown to associate with thrombosis and pregnancy morbidity. However, inclusion of IgA aPL in the classification criteria of the antiphospholipid syndrome (APS) has been debated. We investigated the value of aCL and aβ2GPI IgA aPL in the detection of thrombosis and pregnancy morbidity in addition to the current aPL panel for APS. Methods We included 1,068 patients from eight European medical centers: 259 thrombotic APS patients, 122 obstetric APS patients, 204 non-APS thrombosis patients, 33 non-APS obstetric patients, 60 APS patients with unspecified clinical manifestations, 196 patients with autoimmune diseases, and 194 controls. aCL and aβ2GPI IgG/M/A were detected with four commercial assays and lupus anticoagulant was determined by the local center. Results Positivity for IgA aPL was found in 17 to 26% of the patients with clinical manifestations of APS and in 6 to 13% of the control population. Both aCL and aβ2GPI IgA were significantly associated with thrombosis and pregnancy morbidity. Isolated IgA positivity was rare in patients with clinical manifestations of APS (0.3–5%) and not associated with thrombosis and/or pregnancy morbidity. Addition of IgA to the current criterion panel did not increase odds ratios for thrombosis nor pregnancy morbidity. Conclusion aCL and aβ2GPI IgA are associated with clinical manifestations of APS. However, isolated IgA positivity was rare and not associated with thrombosis or pregnancy morbidity. These data do not support testing for aCL and aβ2GPI IgA subsequent to conventional aPL assays in identifying patients with thrombosis or pregnancy morbidity.


2003 ◽  
Vol 10 (2-4) ◽  
pp. 203-211 ◽  
Author(s):  
Daniel Lopez ◽  
Kazuko Kobayashi ◽  
Joan T. Merrill ◽  
E. Matsuura ◽  
Luis R. Lopez

We recently reported [J. Lipid Res.42(2001), 697;43(2002), 1486;44(2003), 716] thatβ2-glycoprotein I (β2GPI) forms complexes with oxidized LDL (oxLDL) and autoantibodies against these complexes are present in patients with SLE and antiphospholipid syndrome (APS). The relationship ofβ2GPI/oxLDL complexes and IgG autoantibodies againstβ2GPI complexed with oxLig-1 (an oxLDL-derived ligand) with clinical manifestations of APS was studied in 150 APS and SLE patients. Theβ2GPI/oxLDL levels of APS patients were similar to those of SLE patients without APS, but they were significantly higher than healthy individuals. There was no difference in the complex levels among the patients with arterial, venous thrombosis, or pregnancy morbidity. IgG anti-β2GPI/oxLig-1 levels of APS were significantly higher than those of SLE without APS and healthy individuals. Further, antibody levels of APS patients with arterial thrombosis were significantly higher than those patients with venous thrombosis and pregnancy morbidity. Thus, oxidation of LDL leads the complex formation withβ2GPI in SLE and APS patients. In contrast, anti-β2GPI/oxLig-1 autoantibodies were generated only in APS and were strongly associated with arterial thrombosis. These results suggest that autoantibodies againstβ2GPI/oxLDL complexes are etiologically important in the development of atherosclerosis in APS.


2017 ◽  
Vol 44 (05) ◽  
pp. 458-465 ◽  
Author(s):  
Walid Chayouâ ◽  
Hilde Kelchtermans ◽  
Bas Laat

AbstractThe antiphospholipid syndrome (APS) is characterized by vascular thrombosis and/or pregnancy morbidity with the persistent presence of antiphospholipid antibodies (aPLs). Progress is being made in understanding the pathogenesis of the syndrome, but difficulties persist in the identification of patients at risk for thrombosis and/or pregnancy morbidity. Beta-2 glycoprotein I (β2GPI), a plasma protein consisting of five sushi domains, is thought to be the main antigenic target of aPLs. Antibodies recognizing domain I of β2GPI are predominantly present in patients with an elevated risk of thrombosis, whereas antidomain IV/V antibodies are found in nonthrombotic autoimmune diseases. Indeed, domain I antibodies proved to be pathogenic in multiple studies. Retrospective studies have provided evidence for an added clinical value of antidomain I antibodies in the risk stratification of patients with APS. Still, wide ranges of odds ratio exist between studies, probably due to differences in the study and control population, and detection methods used. Despite the proven pathogenicity of antidomain I antibodies and their correlations with clinical manifestations of APS, heterogeneity of the current studies has prohibited their acceptance in the official diagnostic criteria. Well-designed large longitudinal prospective studies with available and new, preferentially functional, assays for the risk stratification of patients with APS are required.


2010 ◽  
Vol 56 (6) ◽  
pp. 930-940 ◽  
Author(s):  
Katrien Devreese ◽  
Marc F Hoylaerts

Abstract Background: The antiphospholipid syndrome (APS) is an important cause of acquired thromboembolic complications and pregnancy morbidity. Its diagnosis is based on clinical and laboratory criteria, defined by strict guidelines. The original clinical and laboratory criteria for the identification of APS patients were published in 1999, in the so-called Sapporo criteria. In 2006 these criteria were revised, and recently more precise guidelines for analysis of the lupus anticoagulant have been provided. However, several questions related to the diagnosis of APS remain unanswered. Content: In addition to providing a historical perspective, this review covers several challenges in the diagnosis of APS with respect to clinical and laboratory features, while highlighting pathogenic pathways of the syndrome. We discuss ongoing dilemmas in the diagnosis of this complex disease. Although antiphospholipid antibodies are found in association with various clinical manifestations, the older established clinical criteria were not substantively altered in the 2006 update. Several laboratory tests recommended in the latest criteria, including phospholipid-dependent coagulation tests for the detection of the lupus anticoagulant and ELISAs for measuring anticardiolipin and β2-glycoprotein I antibodies, still show methodological and diagnostic shortcomings. In addition, antiphospholipid antibodies have been described against other antigens, but their clinical role remains uncertain. Conclusions: Despite updated APS criteria, diagnosis of this syndrome remains challenging. Further research on clinically relevant antibodies and standardization of their detection are needed to improve clinical risk assessment in APS.


2000 ◽  
Vol 7 (2) ◽  
pp. 241-244 ◽  
Author(s):  
Josep Ordi-Ros ◽  
Julieta Villarreal ◽  
Francesc Monegal ◽  
Silvia Sauleda ◽  
Ignacio Esteban ◽  
...  

ABSTRACT The antiphospholipid syndrome (APS) is usually defined by the association of clinical manifestations that comprise venous and/or arterial thrombosis, recurrent fetal losses, and thrombocytopenia, along with the presence of anticardiolipin (aCL) antibodies and/or lupus anticoagulant. Various infectious diseases can induce aCL; however, these antibodies are not usually associated with thrombotic events, as happens with autoimmune diseases, in which these antibodies need the presence of β2-glycoprotein I. Levels of immunoglobulin G (IgG) and IgM aCL antibodies were determined by enzyme-linked immunosorbent assay for 243 patients with chronic hepatitis C virus (HCV) infection and 100 healthy controls. Clinical events of APS, the level of β2-glycoprotein dependence of aCL, the presence of cryoglobulins and other autoantibodies, and cross-reactivity between purified aCL and HCV were evaluated. Positive results for aCL antibodies were found more frequently (3.3%) for the patients with HCV infection than for healthy controls (0%). All positive aCL antibodies were β2-glycoprotein I independent. No significant association was found between aCL antibodies and clinical manifestations of APS, neither was one found between the presence of other autoantibodies or cryoglobulins and that of aCL. Finally, no cross-reactivity between aCL antibodies and HCV antigens was observed. As previously reported, aCL antibodies seem to be an epiphenomenon, and they do not have clinical or laboratory significance in HCV patients.


Lupus ◽  
1998 ◽  
Vol 7 (2_suppl) ◽  
pp. 140-143 ◽  
Author(s):  
Y Shoenfeld ◽  
D Harats ◽  
J George

Atherosclerosis is a multifactorial disease that involves the arterial system. Recent data suggest that immune and autoimmune factors play a dominant role in mediating the progression of atherosclerosis. Among these factors, humoral response to modified forms of LDL and heat-shock proteins has been shown to be influential. The antiphospholipid syndrome (APS) entails clinical manifestations that result from a hypercoagulable state. Antibodies to phospholipids and to β2-glycoprotein I have been suggested to confer the tendency to thrombosis. In a set of recent studies, we have been able to show that generation of antiphospholipid antibodies in mice is associated with enhanced atherosclerosis. These findings imply that APS and atherosclerosis may share a common etiologic background, which may have direct implications for the management of both conditions.


Author(s):  
Meghan E. G. Moore ◽  
Geisa Paulin-Curlee ◽  
Brian D. Johnston ◽  
Connie Clabots ◽  
Chitrita DebRoy ◽  
...  

Hemorrhagic pneumonia (HP) is a rare but highly lethal disease, mainly of dogs and cats, caused by hemolytic Escherichia coli strains that contain cnf1 (encoding cytotoxic necrotizing factor 1). After encountering fatal HP in two dogs, we used contemporary molecular methods, including multi-locus sequence typing and whole genome sequencing, to compare the corresponding case isolates with published HP clinical isolates and newly-obtained fecal E. coli isolates from 20 humans and animals in the index HP case household. We also compared the aggregated HP clinical isolates, which represented 13 discrete strains, by pulsotype with a large, private pulsotype library of diverse-source E. coli . The HP clinical isolates represented a narrow range of phylogenetic group B2 lineages (mainly sequence types 12 and 127), O types (mainly O4 and O6), and H types (mainly H5 and H31), but diverse fimH alleles (type-1 fimbriae adhesin). Their extensive, highly conserved virulence genotypes, which qualified as extraintestinal pathogenic E. coli (ExPEC), encoded diverse adhesins, toxins, iron uptake systems, and protectins. Household surveillance identified multiple HP-like fecal strains, plus abundant between-host strain sharing, including of the household's index HP strain. The pulsotype library search identified, for five HP clinical strains, same-pulsotype human and animal fecal and clinical (predominantly urine) isolates, from diverse locales and time periods. Thus, E. coli strains that cause HP derive from a narrow range of ExPEC lineages within phylogroup B2, contain multiple virulence genes other than cnf1 , are shared extensively between hosts, and likely function in nature mainly as intestinal colonizers and uropathogens. Importance This study clarifies the clonal background and extensive virulence genotypes of the E. coli strains that cause hemorrhagic pneumonia in domestic animals (mainly dogs and cats), shows that such strains circulate among animals and humans, identifies a substantial intestinal colonization component to their lifestyle, and extends their known clinical manifestations to include bacteremia and urinary tract infection. The findings place these strains better into context vis-a-vis current understandings of E. coli phylogeny, ecology, and pathogenesis; identify questions for future research; and may prove relevant for surveillance and prevention efforts.


2015 ◽  
Vol 2015 ◽  
pp. 1-20 ◽  
Author(s):  
Cecilia Beatrice Chighizola ◽  
Tania Ubiali ◽  
Pier Luigi Meroni

Vascular thrombosis and pregnancy morbidity represent the clinical manifestations of antiphospholipid syndrome (APS), which is serologically characterized by the persistent positivity of antiphospholipid antibodies (aPL). Antiplatelet and anticoagulant agents currently provide the mainstay of APS treatment. However, the debate is still open: controversies involve the intensity and the duration of anticoagulation and the treatment of stroke and refractory cases. Unfortunately, the literature cannot provide definite answers to these controversial issues as it is flawed by many limitations, mainly due to the recruitment of patients not fulfilling laboratory and clinical criteria for APS. The recommended therapeutic management of different aPL-related clinical manifestations is hereby presented, with a critical appraisal of the evidence supporting such approaches. Cutting edge therapeutic strategies are also discussed, presenting the pioneer reports about the efficacy of novel pharmacological agents in APS. Thanks to a better understanding of aPL pathogenic mechanisms, new therapeutic targets will soon be explored. Much work is still to be done to unravel the most controversial issues about APS management: future studies are warranted to define the optimal management according to aPL risk profile and to assess the impact of a strict control of cardiovascular risk factors on disease control.


2012 ◽  
Vol 39 (3) ◽  
pp. 516-523 ◽  
Author(s):  
ELEFTHERIA P. GRIKA ◽  
PANAYIOTIS D. ZIAKAS ◽  
ELIAS ZINTZARAS ◽  
HARALAMPOS M. MOUTSOPOULOS ◽  
PANAYIOTIS G. VLACHOYIANNOPOULOS

Objective.To describe morbidity, organ damage, mortality, and cause of death in patients with antiphospholipid syndrome (APS).Methods.Descriptive analysis of 135 patients. Patients were clustered according to initial event: arterial thrombosis including stroke (AT; n = 46), venous thrombosis including pulmonary emboli (VT; n = 53), or pregnancy morbidity (PM; n = 36). Disease progression according to initial event and prevalence of organ damage was observed.Results.APS occurs among young individuals (mean age 33.3 ± 11.9 yrs). One-third of the patients have APS secondary to systemic lupus erythematosus (SLE) or SLE-like disease. A broad spectrum of clinical manifestations mark the disease onset even before diagnosis. The pattern of initial presentation is preserved with regard to second event; VT is followed by VT (84%), AT is followed by AT (95%), and PM is followed by PM (88.9%). The highest morbidity is attributed to neurologic damage. PM is more likely to be followed by a second event, yet is associated with less organ damage than AT and VT. After a mean followup of 7.55 years, 29% of patients experienced organ damage and 5 died, with Systemic Lupus International Collaborating Clinics score associated with increased mortality (HR 1.31, 95% CI 1.07–1.60, p = 0.01, per 1-unit increase); hematological malignancies occurred in 2 patients after a cumulative followup of 1020 person-years. Coexistent SLE adds significant damage in patients with APS.Conclusion.APS is a disease of young individuals, who experience increased morbidity. Neurologic damage is the most common cause of morbidity. AT at presentation as well as coexistent SLE are associated with poor outcome.


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