Antiphospholipid antibodies permeabilize and depolarize brain synaptoneurosomes

Movement disorders in systemic lupus erythematosus and the antiphospholipid syndrome

Movement disorders (MDs), particularly chorea, may be the presenting neurological complication of systemic lupus erythematosus (SLE) and the antiphospholipid syndrome (APS), but the association is not often initially recognized. Current evidence suggests an autoimmune mechanism related to antiphospholipid antibodies in these two conditions, although the antigenic target within the central nervous system has not yet been identified. Based on a comprehensive review of the literature, this article summarizes the current knowledge on MDs in SLE and APS. A high index of suspicion is required to make an early diagnosis and initiate appropriate treatment to provide symptomatic relief and to prevent other systemic complications related to the autoimmune process.

Antiphospholipid-related chorea

Chorea is a movement disorder which may be associated with immunologic diseases, in particular in the presence of antiphospholipid antibodies (aPL). Choreic movements have been linked to the isolated presence of plasmatic aPL, or to primary, or secondary antiphospholipid syndrome. The highest incidence of aPL-related chorea is detected in children and females. The presentation of chorea is usually subacute and the course monophasic. Choreic movements can be focal, unilateral, or generalized. High plasmatic titers of aPL in a choreic patient can suggest the diagnosis of aPL-related chorea; neuroimaging investigation does not provide much additional diagnostic information. The most relevant target of aPL is β2-glycoprotein I, probably responsible for the thrombotic manifestations of antiphospholipid syndrome. Etiology of the movement disorder is not well understood but a neurotoxic effect of aPL has been hypothesized, leading to impaired basal ganglia cell function and development of neuroinflammation. Patients affected by aPL-related chorea have an increased risk of thrombosis and should receive antiplatelet or anticoagulant treatment.

Neurological impairment in experimental antiphospholipid syndrome is associated with increased ligand binding to hippocampal and cortical serotonergic 5-HT1A receptors

The antiphospholipid syndrome (APS) is an autoimmune disease where the presence of high titers of circulating autoantibodies causes thrombosis with consecutive infarcts. In experimental APS (eAPS), a mouse model of APS, behavioral abnormalities develop in the absence of vessel occlusion or infarcts. Using brain hemispheres of control and eAPS mice with documented neurological and cognitive deficits, we checked for lymphocytic infiltration, activation of glia and macrophages, as well as alterations of ligand binding densities of various neurotransmitter receptors to unravel the molecular basis of this abnormal behavior. Lymphocytic infiltrates were immunohistochemically characterized using antibodies against CD3, CD4, CD8 and forkhead box P3 (Foxp3), respectively. GFAP, Iba1 and CD68-immunohistochemistry was performed, to check for activation of astrocytes, microglia and macrophages. Ligand binding densities of NMDA, AMPA, GABAA and 5-HT1A receptors were analyzed by in vitro receptor autoradiography. No significant inflammatory reaction occurred in eAPS mice. There was neither activation of astrocytes or microglia nor accumulation of macrophages. Binding values of excitatory and inhibitory neurotransmitter receptors were largely unchanged. However, ligand binding densities of the modulatory serotonergic 5-HT1A receptors in the hippocampus and in the primary somatosensory cortex of eAPS mice were significantly upregulated which is suggested to induce the behavioral abnormalities observed.

Seizures in primary antiphospholipid syndrome: the relevance of smoking to stroke

Objectives. To evaluate the frequency of seizures in primary antiphospholipid syndrome (PAPS) and their possible clinical and laboratory associations. Methods. Eighty-eight PAPS patients (Sydney's criteria) were analyzed by a standard interview, physical examination and review of medical charts. Risk factors for seizures, clinical manifestations, associated comorbidities, and antiphospholipid antibodies were evaluated. Results. Nine (10.2%) patients with seizures were identified, 77.8% had convulsions onset after PAPS diagnosis. Mean age, gender, and race were comparable in groups with or without seizures. Interestingly, a higher frequency of current smoking (44.4 versus 10.1%, P = 0.019) was observed in the first group. Stroke, Sneddon's syndrome, and livedo reticularis were more frequent in PAPS patients with seizures than those without seizures, although not statistically significant (P > 0.05). Comparison between patients with seizures onset after PAPS diagnosis (n = 7) and those without convulsions (n = 79) demonstrated a higher frequency of current smoking (42.9 versus 10%, P = 0.042) and stroke in the first group (71.4 versus 30.4%, P = 0.041). Regression analysis confirmed that smoking (P = 0.030) and stroke (P = 0.042) were independently associated to seizures. Conclusion. About 10.2% of PAPS patients had convulsions, predominantly after PAPS diagnosis, and seizures were associated to current smoking and stroke.

A patient with bipolar disorder and antiphospholipid syndrome

Antiphospholipidsyndrome (APS) is an autoimmune disorder which causes a hyper-coagulable state characterized by recurrent thrombosis. It has a diverse range of central nervous system manifestations. We describe a case of a 61 year old man with bipolar disorder and APS, and we compare this to a previously reported case. Additionally, we reviewed literature regarding APS-related markers and the relationship of APS to other psychiatric and neurologic illnesses. We discuss possible mechanisms for an association between APS and bipolar disorder. We encourage clinicians to be aware of this possible relationship and have proposed research strategies.

Cognitive impairment in antiphospholipid syndrome: evidence from animal models

Although antiphospholipid syndrome (APS) is a multisystem prothrombotic condition, its inflammatory nature has been increasingly recognized in recent years. Stroke and transitory ischemic attacks are the neurological manifestations included in APS criteria, however many other neurological involvements have been attributed to antiphospholipid antibodies (aPL), such as seizures, transverse myelitis, and cognitive impairment. In this article we will review evidence from animal model that explain the role of aPL in cognition.

Autoantibodies as biomarkers for the prediction of neuropsychiatric events in systemic lupus erythematosus

OBJECTIVE

Neuropsychiatric events occur unpredictably in systemic lupus erythematosus (SLE) and most biomarker associations remain to be prospectively validated. This study examined a disease inception cohort of 1047 SLE patients to determine which autoantibodies at enrolment predicted subsequent neuropsychiatric events.

METHODS

Patients with a recent SLE diagnosis were assessed prospectively for up to 10 years for neuropsychiatric events using the American College of Rheumatology case definitions. Decision rules of graded stringency determined whether neuropsychiatric events were attributable to SLE. Associations between the first neuropsychiatric event and baseline autoantibodies (lupus anticoagulant (LA), anticardiolipin, anti-β(2) glycoprotein-I, anti-ribosomal P and anti-NR2 glutamate receptor) were tested by Cox proportional hazards regression.

RESULTS

Disease duration at enrolment was 5.4 ± 4.2 months, follow-up was 3.6 ± 2.6 years. Patients were 89.1% female with mean (±SD) age 35.2 ± 13.7 years. 495/1047 (47.3%) developed one or more neuropsychiatric event (total 917 events). Neuropsychiatric events attributed to SLE were 15.4% (model A) and 28.2% (model B). At enrolment 21.9% of patients had LA, 13.4% anticardiolipin, 15.1% anti-β(2) glycoprotein-I, 9.2% anti-ribosomal P and 13.7% anti-NR2 antibodies. LA at baseline was associated with subsequent intracranial thrombosis (total n=22) attributed to SLE (model B) (HR 2.54, 95% CI 1.08 to 5.94). Anti-ribosomal P antibody was associated with subsequent psychosis (total n=14) attributed to SLE (model B) (HR 3.92, 95% CI 1.23 to 12.5, p=0.02). Other autoantibodies did not predict neuropsychiatric events.

CONCLUSION

In a prospective study of 1047 recently diagnosed SLE patients, LA and anti-ribosomal P antibodies are associated with an increased future risk of intracranial thrombosis and lupus psychosis, respectively.

Chorea in primary antiphospholipid syndrome is associated with rheumatic fever

The aim of the study is to evaluate the frequency of chorea in a cohort of primary antiphospholipid syndrome (PAPS) patients and their possible clinical and laboratory associations. The records of 88 PAPS patients, fulfilling Sapporo criteria, followed up at the rheumatology outpatient clinic, were analyzed in order to determine the frequency of chorea. Risk factors for chorea, clinical manifestations, associated comorbidities, serologic features and treatment strategies were analyzed. Eighty-eight PAPS patients were evaluated. Mean age was 40.6 ± 11.1 years, and 91% of them were Caucasian and 91% women. Four (4.5%) patients with chorea were identified: 2 of them (50%) had only one chorea episode and 2 (50%) had recurrent chorea. All patients had chorea onset before PAPS diagnosis. Mean age, gender and ethnical distribution were comparable in groups with or without seizures (P > 0.05). Interestingly, the comparison of the 4 PAPS patients with chorea with those without this abnormality (n = 84) demonstrated a lower BMI [21.1 (18-24.2) vs. 27.5 (17.5-40.9) kg/m(2), P = 0.049] and frequency of venous events (0 vs. 63.1%, P = 0.023) in the first group. A higher frequency of rheumatic fever (75% vs. 0, P < 0.001) and thrombocytopenia (75 vs. 21.4%, P = 0.041) was observed in PAPS individuals with chorea. Both groups were alike regarding the other clinical APS manifestations, disease duration, risk factors for cerebrovascular diseases, use of drugs and antiphospholipid antibodies (P > 0.05). This study demonstrated that 4.5% of PAPS patients had chorea, predominately before PAPS diagnosis, and this neurological abnormality was associated with rheumatic fever and thrombocytopenia. These data reinforce the need for RF diagnosis in those PAPS patients with chorea.

Movement disorders in paraneoplastic and autoimmune disease

PURPOSE OF REVIEW

The most relevant advances in immune-mediated movement disorders are described, with emphasis on the clinical--immunological associations, novel antigens, and treatment.

RECENT FINDINGS

Many movement disorders previously considered idiopathic or degenerative are now recognized as immune-mediated. Some disorders are paraneoplastic, such as anti-CRMP5-associated chorea, anti-Ma2 hypokinesis and rigidity, anti-Yo cerebellar ataxia and tremor, and anti-Hu ataxia and pesudoathetosis. Other disorders such as Sydenham's chorea, or chorea related to systemic lupus erythematosus and antiphospholipid syndrome occur in association with multiple antibodies, are not paraneoplastic, and are triggered by molecular mimicry or unknown mechanisms. Recent studies have revealed a new category of disorders that can be paraneoplastic or not, and associate with antibodies against cell-surface or synaptic proteins. They include anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis, which may cause dyskinesias, chorea, ballismus or dystonia (NMDAR antibodies), the spectrum of Stiff-person syndrome/muscle rigidity (glutamic acid decarboxylase, amphiphysin, GABA(A)-receptor-associated protein, or glycine receptor antibodies), neuromyotonia (Caspr2 antibodies), and opsoclonus--myoclonus--ataxia (unknown antigens).

SUMMARY

Neurologists should be aware that many movement disorders are immune-mediated. Recognition of these disorders is important because it may lead to the diagnosis of an occult cancer, and a substantial number of patients, mainly those with antibodies to cell-surface or synaptic proteins, respond to immunotherapy.

Antiphospholipid antibodies and the brain: a consensus report

This report discusses the difference between antiphospholipid antibodies (aPL) as a predictor for first and recurrent ischemic stroke, whether or not concomitant systemic lupus erythematosus (SLE) increases aPL-associated risk, and the association of aPL with other neurological manifestations. The neurological manifestations covered in this report were selected because they are among the most common, including cognitive dysfunction, headache, multiple sclerosis and seizures/epilepsy. Recommendations are made regarding further research that is needed to clarify remaining uncertainties.

Antibody binding to neuronal surface in movement disorders associated with lupus and antiphospholipid antibodies

AIM

Systemic lupus erythematosus is a multi-organ autoimmune disorder associated with autoantibodies of complex diversity. Antiphospholipid antibodies (aPL), which are commonly associated with lupus, create a pro-thrombotic tendency, but are also associated with non-thrombotic neurological features. Movement disorders are rare neuropsychiatric complications of lupus and antiphospholipid syndrome, and autoimmune and thromboembolic disease mechanisms have been proposed.

METHOD

We describe the clinical features, investigation findings, treatment, and outcome of six paediatric participants with movement disorders associated with lupus and/or aPL (six females, median age 13 y, range 8-15). To examine the autoantibody hypothesis, we used a neuronal cell line with dopaminergic characteristics and measured serum antibody binding to neuronal cell-surface antigens using flow cytometry. For comparison with the six participants, we used serum from healthy individuals (n=12, six females, median age 11 y, range 9-13) and children with other neurological diseases (n=13, seven females, median age 7 y, range 2-15).

RESULTS

Of the six participants, two had lupus only, two had lupus with aPL, and two had aPL only. The movement disorder was chorea in four and parkinsonism in two. All four participants with chorea had aPL and movement disorder relapses. The two participants with parkinsonism did not have aPL, but had a progressive course until rituximab or plasma exchange resulted in neuropsychiatric remission. All six participants demonstrated elevated serum antibody binding to neuronal cell-surface antigens compared with healthy individuals and those with other neurological diseases.

INTERPRETATION

This report supports the association of chorea with aPL, but suggests a different autoimmune mechanism operates in lupus parkinsonism. The presence of antibody binding to neuronal cell-surface antigens supports a possible direct action of autoantibodies on neurons in patients with movement disorders associated with lupus and aPL.

Pathophysiology of the antiphospholipid antibody syndrome

Antiphospholipid antibodies (aPL) are associated with the recurrent pregnancy loss and thrombosis that characterizes the antiphospholipid antibody syndrome (APS). Although the ontogeny of these pathogenic antibodies has not been fully elucidated, there is evidence that indicates the involvement of both genetic and environmental factors. The ability of aPL to induce a procoagulant phenotype in APS patients plays a central role in the development of arterial and venous thrombotic manifestations typical of the disease. Inflammation serves as a necessary link between this procoagulant phenotype and actual thrombus development and is an important mediator of the placental injury seen in APS patients with obstetric complications. Recent evidence has indicated a role for abnormal cellular proliferation and differentiation in the pathophysiology of APS, especially in those patients with pregnancy morbidity and other more atypical manifestations that have no identifiable thrombotic cause. The interplay of genetic and environmental factors responsible for aPL development and the mechanisms by which these antibodies produce disease in APS patients is the focus of this review.

Antiphospholipid syndrome and the brain in pediatric and adult patients

The most common neurological manifestations of antiphospholipid syndrome (APS) in all age-groups include stroke and transient ischemic attacks due to arterial thromboses and cerebral ischemia. Antiphospholipid antibodies may cause additional non-criteria neurological impairments through vascular, neuroinflammatory and direct neuronal effects. Anti-aggregant or anticoagulant therapies are indicated for APS-related ischemic strokes. Treatment regimens for asymptomatic antibody-positive patients and those with refractory or recurrent disease remain controversial. There is scant literature on the epidemiology and therapy of neurological APS manifestations in pediatric patients. Assessments of modifiable cardiovascular and inherited thrombophilia risk factors are essential in patients with APS. There may be a role for novel neuroimaging modalities in quantifying APS-related microstructural brain damage. The clinical utility of statins, antimalarials, angiotensin-converting enzyme inhibitors, and thrombin inhibitors warrant further research.

Neuroprotective effect of Fn14 deficiency is associated with induction of the granulocyte-colony stimulating factor (G-CSF) pathway in experimental stroke and enhanced by a pathogenic human antiphospholipid antibody

Using a transgenic mouse model of ischemic stroke we checked for a possible interaction of antiphospholipid antibodies (aPL) which often cause thromboses as well as central nervous system (CNS) involvement under non-thrombotic conditions and the TWEAK/Fn14 pathway known to be adversely involved in inflammatory and ischemic brain disease. After 7 days, infarct volumes were reduced in Fn14 deficient mice and were further decreased by aPL treatment. This was associated with strongest increase of the endogenous neuroprotective G-CSF/G-CSF receptor system. This unexpected beneficial action of aPL is an example for a non-thrombogenic action and the double-edged nature of aPL.

Cognitive dysfunction and white matter abnormalities in antiphospholipid syndrome

Diagnosis of the antiphospholipid syndrome (APS) requires that a patient have both a clinical event (thrombosis or pregnancy loss) and persistently positive antiphospholipid antibodies (aPL). Although stroke and transient ischemic attack are the most common neurologic manifestations of APS, both cognitive dysfunction and magnetic resonance imaging (MRI) white matter hyperintensities can occur in aPL-positive patients (with or without APS). Relatively little is known about the cognitive pattern in aPL-positive patients; MRI white matter hyperintensities may be related to underlying attentional and executive cognitive impairment. Studies with sophisticated neuroimaging techniques aimed to better understand MRI white matter hyperintensities may eventually facilitate our understanding of cognitive dysfunction in aPL-positive patients.

Antiphospholipid syndrome and central nervous system

Classification criteria, etiology, pathogenesis, major central nervous system (CNS) manifestations of the antiphospholipid syndrome (APS), as well as diagnostic and therapeutic approach are discussed in the article, supported by several MRI findings to illustrate differential complexity of selected topics. Close interplay of inflammation, autoimmunity, coagulation cascade, vasculature bed, neuron physiology and demyelinization in APS is elaborated. Cerebrovascular disease, multiple sclerosis-like syndrome, seizures, cognitive disfunction, headache and migraine, chorea and catastrophic antiphospholipid syndrome (CAPS) are discussed as the most prominent CNS manifestations of the APS.

Neurological manifestations of antiphospholipid syndrome

BACKGROUND

Neurologic disorders are among the most common and important clinical manifestations associated with the antiphospholipid syndrome (APS). It is characterized by diverse neurological manifestations. These include stroke, transient ischaemic attack, Sneddon's syndrome, convulsions/epilepsy, dementia, cognitive deficits, headaches/migraine, chorea, multiple sclerosis-like, transverse myelitis, ocular symptoms and Guillain-Barré syndrome.

MATERIAL AND METHODS

We review the latest data about neurologic disorders and APS.

RESULTS

In patients under 45 years of age, 20% of strokes are potentially associated with APS. Our study group recently reported a correlation between primary APS and peripheral neuropathy. Only one study investigated the occurrence of peripheral neuropathy in patients diagnosed with PAPS through electrophysiological study and showed alterations in 35% of patients. The mechanism of nervous system involvement in APS is considered to be primarily thrombotic. However, other mechanisms have been described, such as antiphospholipid antibodies that bind to the neural tissue, deregulating their functions and having an immediate pathogenic effect.

CONCLUSIONS

This review summarizes the latest data regarding the clinical aspects, radiological and therapeutic of major neurologic manifestations associated with antiphospholipid antibodies.

Non-criteria manifestations of antiphospholipid syndrome

Only few studies have addressed the pathogenesis and treatment of the non-criteria manifestations of antiphospholipid antibodies (aPL) such as thrombocytopenia, nephropathy, cardiac valve disease, cognitive dysfunction, skin ulcers, or diffuse pulmonary hemorrhage. There is no consensus on the management of these manifestations; they may occur despite full-dose anticoagulation or may not improve if anticoagulation is initiated after their discovery. This brief review may help physicians in the management of the non-criteria manifestations of aPL.

Moderate versus high-titer persistently anticardiolipin antibody positive patients: are they clinically different and does high-titer anti-beta 2-glycoprotein-I antibody positivity offer additional predictive information?

The association between antiphospholipid antibodies (aPL) and clinical events is stronger with a positive lupus anticoagulant (LA) test, higher anticardiolipin antibody (aCL) titers, and/or higher anti-beta(2)-glycoprotein-I antibody (abeta( 2)GPI) titers. The objective of this study was to determine the clinical characteristics of persistently high-titer (> or =80 U) aCL-positive patients compared with those with persistent moderate aCL titers (40-79 U). Second, we analyzed whether high-titer abeta(2)GPI test adds predictive information in persistently moderate-to-high titer aCL-positive patients. In this cross-sectional study, the primary analysis compared the clinical and aPL characteristics of 58 patients with at least two moderate-titer aCL results to another 85 patients with at least two high-titer aCL results. In the secondary analysis of patients with at least two abeta(2)GPI test results, we compared 29 patients with 'aCL 40-79 U and abeta( 2)GPI < 80 U' profiles with 8 patients with 'aCL 40-79U and abeta(2)GPI > or = 80 U', and also compared 27 patients with 'aCL > 80 U and abeta(2)GPI < 80 U' with 32 patients with 'aCL > 80 U and abeta(2)GPI > or = 80 U'. Although aPL-related vascular and pregnancy events were similar between the moderate- and high-titer aCL groups, the number of patients with positive LA tests (RR 2.06, CI 1.38-3.08, p < 0.01) and with at least one non-criteria aPL manifestation (RR 1.66, CI 1.20-2.30, p = 0.0005) were significantly higher in the high-titer aCL group. While magnetic resonance imaging (MRI) white matter changes were statistically more common in the high-titer aCL group (RR 2.03, CI 1.04-3.94, p = 0.02), there was a trend towards increased prevalence of livedo reticularis, cardiac valve disease, and cognitive dysfunction occurring in the high-titer aCL group. The secondary analysis showed that MRI white matter changes, cardiac valve disease, and cognitive dysfunction were proportionally more common in the high-titer abeta( 2)GPI groups, suggesting a linear relationship between non-criteria aPL manifestations and aPL titers. Our results suggest that patients with high aCL titers, compared with those with moderate titers, are more likely to have a positive LA test and a higher prevalence of non-criteria aPL manifestations. Furthermore, high-titer abeta(2)GPI positivity may further increase the prevalence of non-criteria aPL manifestations in moderate- or high-titer aCL-positive patients.

Hyperactivity induced by antiphospholipid syndrome serum

Antiphospholipid syndrome (APS) is a multisystem disorder characterized by arterial and venous thrombosis, pregnancy morbidity, and neuropsychiatric manifestations. Antiphospholipid IgG injected intracerebroventricularly (i.c.v.) cause behavioral hyperactivity in mice. In the present study we investigated the effects of APS whole-serum i.c.v. administration in female Balb/C mice. Control mice were injected with serum derived from healthy subjects or saline solution. Behavior was assessed by the staircase apparatus which combines locomotor (stair-climbing) exploratory activities and rearing as a measure of anxiety. Mice injected with serum from APS patients or serum from normal subjects showed a trend to an increase in the number of stairs climbed in the APS group. The results suggest a differential effect of specific IgG and other serum components in the CNS manifestations of APS.

Redox-reactive autoantibodies in Alzheimer's patients' cerebrospinal fluids: Preliminary studies

Oxidation of cerebrospinal fluid (CSF) causes differential unmasking of autoantibodies in control CSF vs. that obtained from postmortem CSF samples from autopsy confirmed Alzheimer's disease (AD) cases. This study demonstrates that normal CSF from both living patients and from non-demented autopsy cases contains redox-reactive autoantibodies with specificities that include antiphospholipid antibodies (aPL). In contrast, CSF from autopsy confirmed AD subjects contained little or no redox-reactive aPL autoantibodies. Tests using an in vitro rat synaptosome model showed that the oxidized CSF autoantibodies from a normal individual can cause ERK1/2 phosphorylation at a level consistent with reports of pathogenic changes found in brain tissues from AD patients. The decrease or absence of redox-reactive antibodies in CSF from Alzheimer's patients suggests that these antibodies may have been previously unmasked by the oxidative conditions that exist in the CNS in AD patients. These unmasked autoantibodies could then bind to neuronal tissues and possibly participate in the initial cascade leading to the dementia in Alzheimer's. To our knowledge, this is the first description of resident autoantibodies with the potential to cause brain cell damage documented in CSF without a breech in the blood-brain barrier. The untimely and inappropriate physiological unmasking of these redox-reactive autoantibodies in AD patients CSF may represent a valuable biomarker for diagnosis and progression of this and perhaps other neurodegenerative diseases which also have oxidative stress components. These novel autoantibody observations may stimulate thoughts about additional therapeutic approaches and warrant similar studies for other neurodegenerative diseases.

Antibodies to glutamate receptor subtype 3 (GluR3) are found in some patients suffering from epilepsy as the main disease, but not in patients whose epilepsy accompanies antiphospholipid syndrome or Sneddon's syndrome

Autoantibodies (Ab's) to the "B" peptide (amino acids 372-395) of glutamate/AMPA receptor subtype 3 (GluR3) are found in serum and cerebrospinal fluid of some patients with different types of epilepsy. Since such anti-GluR3B Ab's can activate and/or kill neurons in vitro and in vivo, they may contribute to epilepsy. To investigate whether anti-GluR3B Ab's may also be relevant to epilepsy when it accompanies some autoimmune-diseases, we tested for these Ab's in patients suffering from epilepsy that accompanies anti-phospholipid syndrome (APS) or Sneddon's syndrome (SNS), both being autoimmune-diseases with frequent neurological complications. We tested 77 pediatric patients whose epilepsy is their main disease; 31 adult patients whose epilepsy accompanies APS (primary or SLE-associated) or SNS; 45 epilepsy-free APS and SNS patients; and 90 healthy controls. Compared to the controls, significantly elevated anti-GluR3B Ab's were found in 22/77 (29%) patients whose epilepsy is their main disease, but in none of the patients whose seizures accompany APS or SNS. Yet, all the APS and SNS patients harbored the characteristic anti-phospholipid Ab's (aPL), directed against cardiolipin and beta2-glycoprotein I, and had lupus anti-coagulant. Thus, anti-GluR3B Ab's are not crossreactive with aPL, and not produced as a non-specific consequence of seizures on the one hand, or autoimmune-diseases on the other. Taken together with new findings accumulated recently in our lab, we suggest that anti-GluR3B Ab's are produced primarily in the periphery due to specific/non-specific "irritation" of the immune system, and that once they reach the brain via a leaky blood-brain barrier they may cause neuronal/glial damage and facilitate the outburst of epilepsy and additional neurological abnormalities. In contrast, the presence of anti-GluR3B Ab's does not seem to increase the probability of developing APS, SNS or the seizures that often accompany these autoimmune-diseases. These findings may have important diagnostic and therapeutic implications.

Autoantibodies involved in neuropsychiatric manifestations associated with systemic lupus erythematosus

In the course of Systemic Lupus Erythematosus (SLE), a variety of neuropsychiatric disturbances is reported with a prevalence ranging from 17% to 75%. The diagnosis of these syndromes is difficult and requires a careful psychiatric evaluation. Distinct autoantibodies detectable in serum or cerebrospinal fluid of patients with SLE are associated with the presence of neuropsychiatric disorders. These autoantibodies may have a pathogenic relevance in neuropsychiatric SLE or they may be merely an epiphenomenon. This review describes the various autoantibodies reported to be associated with neuropsychiatric manifestations in SLE and discusses their possible role.

Antiphospholipid syndrome induction exacerbates a transgenic Alzheimer disease model on a female background

The antiphospholipid syndrome (APS) is characterized by antiphospholipid antibodies (aPL) and vascular brain disease which is often associated with dementia. We examined the neurodegenerative pathological processes underlying APS by inducing APS in a transgenic animal model of Alzheimer's disease. Female C57B6/SJL mice carrying the APP(695)SWE mutation (Tg2576) and wild-type (wt) controls were immunized with β₂-glycoprotein-I (APS mice) or adjuvant alone (controls) at 4 months of age. At the age of 8 months the APP-APS mice developed high levels of aPL associated with motor hypoactivity in a staircase test (p<0.03 by t-test) and impaired performance in the cognitive T-maze (p<0.02 for main effect of treatment by repeated measures ANOVA) relative to APP-CFA mice and controls. wt-APS and wt-control did not differ significantly in their behavior or cognition. Histological studies revealed mature plaques only in the APP-APS group which also had higher amyloid load and number of activated microglia compared to all other groups. The results indicate a significant interaction between APP genotype and the induction of APS on a female background. The mechanisms involved may also be important in human APS-AD co-morbidity.

Neuropsychiatric lupus and infectious triggers

Infections can act as environmental triggers inducing or promoting systemic lupus erythematosus (SLE) in genetically predisposed individuals. The aim of the present study was to compare the titres of antibodies (Abs) to infectious agents with neuropsychiatric (NPSLE) clinical manifestations. The sera of 260 individuals (120 patients with SLE and 140 geographic controls) were evaluated for the titres of Epstein bar virus (EBV), cytomegalovirus (CMV), toxoplasma, rubella and syphilis Abs using the BioPlex 2200 Multiplexed Immunoassay method (BioRad) and by the ELISA method for Helicobacter pylori and Hepatitis B core Ag. All BioPlex 2200 kits used were in developmental stages. Data analysis was performed using SPSS 9.0 statistical analysis software (SPSS Inc., Chicago, IL, USA, 1999). Correlation analysis indicated that rubella IgM Ab titres were marginally, positively associated with psychosis ( P = 0.09). No other associations were detected between the 17 infectious Abs and five NP manifestations. When the positivity cut-off for anti-rubella IgM Abs was set at three standard deviations above normal, three positive subjects were identified: one patient with psychosis and one with depression, for a total NPSLE prevalence of 33.3%. On the contrary, the prevalence of NPSLE in the remaining subjects was 6.5%. Marginally significant correlations between elevated titres of rubella IgM Ab with psychosis and depression were found. Although this nearly 5-fold increase is not statistically significant, it appears that in a larger sample size, significance would be reached. This is the first study reported that examined the correlation of NPSLE manifestations with anti-infectious Abs.

Autoantibodies and neuropsychiatric events at the time of systemic lupus erythematosus diagnosis: results from an international inception cohort study

OBJECTIVE

To examine, in an inception cohort of systemic lupus erythematosus (SLE) patients, the association between neuropsychiatric (NP) events and anti-ribosomal P (anti-P), antiphospholipid (lupus anticoagulant [LAC], anticardiolipin), anti-beta2-glycoprotein I, and anti-NR2 glutamate receptor antibodies.

METHODS

NP events were identified using the American College of Rheumatology case definitions and clustered into central/peripheral and diffuse/focal events. Attribution of NP events to SLE was determined using decision rules of differing stringency. Autoantibodies were measured without knowledge of NP events or their attribution.

RESULTS

Four hundred twelve patients were studied (87.4% female; mean +/- SD age 34.9 +/- 13.5 years, mean +/- SD disease duration 5.0 +/- 4.2 months). There were 214 NP events in 133 patients (32.3%). The proportion of NP events attributed to SLE varied from 15% to 36%. There was no association between autoantibodies and NP events overall. However, the frequency of anti-P antibodies in patients with central NP events attributed to SLE was 4 of 20 (20%), versus 3 of 107 (2.8%) in patients with other NP events and 24 of 279 (8.6%) in those with no NP events (P = 0.04). Among patients with diffuse NP events, 3 of 11 had anti-P antibodies (27%), compared with 4 of 111 patients with other NP events (3.6%) and 24 of 279 of those with no NP events (8.6%) (P = 0.02). Specific clinical-serologic associations were found between anti-P and psychosis attributed to SLE (P = 0.02) and between LAC and cerebrovascular disease attributed to SLE (P = 0.038). There was no significant association between other autoantibodies and NP events.

CONCLUSION

Clinically distinct NP events attributed to SLE and occurring around the time of diagnosis were found to be associated with anti-P antibodies and LAC. This suggests that there are different autoimmune pathogenetic mechanisms, although low sensitivity limits the clinical application of testing for these antibodies.

Antiphospholipid antibodies in blood and cerebrospinal fluids of patients with psychosis

Antiphospholipid antibodies (aPL) have been reported in the cerebrospinal fluids (CSF) of neurology patients but no CSF studies with psychiatric patients exist. We tested serum from 100 hospitalized psychotic patients having hallucinations and/or delusions for aPL. Patients with positive serum aPL findings were asked to submit CSF for aPL testing. Five CSF samples had aPL specificities not found in the patient's serum suggesting the possibility of intrathecal synthesis. Specificity and isotype discordance between CSF and blood aPL in these psychiatric patients implicates a central nervous system independent autoimmune process that may have an underlying association with the pathophysiology of their diseases.

Seizures in patients with systemic lupus erythematosus: data from LUMINA, a multiethnic cohort (LUMINA LIV)

OBJECTIVE

To examine the predictors of time-to-seizure occurrence and their impact on damage accrual and mortality in LUMINA, a multiethnic (Hispanic, African American and Caucasian) cohort of patients with systemic lupus erythematosus.

METHODS

Seizures were defined as per the American College of Rheumatology (ARC) nomenclature and case definitions for neuropsychiatric lupus syndromes. Factors associated with time-to-seizure occurrence occurring at or after diagnosis (TD) of systemic lupus erythematosus were examined by univariable and multivariable Cox proportional hazard regression analyses. The impact of seizures on damage accrual and mortality was also examined by multivariable analyses after adjusting for variables known to affect these outcomes.

RESULTS

A total of 600 patients were included in these analyses. Of them, 40 (6.7%) developed seizures at or after TD; by multivariable analyses, disease activity and younger age were independent predictors of a shorter time-to-seizure occurrence (HR = 1.10 and 1.04; 95% CI 1.04 to 1.15 and 1.00 to 1.08, p = 0.0004 and 0.0304, respectively) whereas mucocutaneous involvement (HR = 0.34, 95% CI 0.16 to 0.41, p = 0.0039) and hydroxychloroquine use (HR = 0.35, 95% CI 0.15 to 0.80, p = 0.0131) were independent predictors of a longer time-to-seizure occurrence. Seizures were an independent contributor to damage accrual but not to mortality.

CONCLUSIONS

Seizures tend to occur early in the course of systemic lupus erythematosus, and contribute to damage accrual. Younger age and disease activity are independent predictors of a shorter time-to-seizure occurrence; antimalarials appear to have a protective role in seizure occurrence.

Clinical and positron emission tomography findings of chorea associated with primary antiphospholipid antibody syndrome

A fourteen-year-old right-handed male with a history of attention deficit hyperactivity disorder (ADHD) presented with alternating hemichorea. Laboratory findings included elevated anticardiolipin IgG and anti-beta(2)-glycoprotein I IgG, which were consistent with primary antiphospholipid antibody syndrome. Positron emission tomography (PET) imaging revealed altered striatal metabolism in his left putamen while he was exhibiting right-sided hemichorea. His symptoms resolved on prednisone; however, his antiphospholipid antibody profile remained markedly abnormal despite being symptom-free for 26 months.

Neurological manifestations of the antiphospholipid syndrome: risk assessments and evidence-based medicine

The antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterised by autoantibody production and vascular thrombosis or pregnancy morbidity. Autoantibodies generated against phospholipid and phospholipid-binding proteins often impair phospholipid-dependent clotting assays (lupus anticoagulants). These autoantibodies activate endothelial cells, platelets and biochemical cascades and can exist in autoimmune disorders such as lupus. Consistently positive antibodies may worsen the severity of thrombo-occlusive disease. The most common neurological manifestations of APS include stroke and transient ischaemic attacks due to arterial thromboses. Antiphospholipid antibodies may cause additional neurological impairments through both vascular and immune mechanisms. Antiaggregant or anticoagulant therapies are indicated for APS-related ischaemic strokes. Treatment regimens for asymptomatic antibody-positive patients and those with refractory disease remain controversial. There is scant literature on neurological APS manifestations in paediatric patients. Assessment of traditional cardiovascular and inherited thrombophilia risk factors is essential in patients with APS. Modifiable risk factors and valvular heart disease may worsen thrombotic and cerebrovascular outcomes. Alternative therapies such as statins, anti-malarials, angiotensin-converting enzyme inhibitors and thrombin inhibitors warrant further research.

Autoantibodies Involved in Neuropsychiatric SLE and Antiphospholipid Syndrome

OBJECTIVE

We sought (1) to identify and (2) to define the association of all reported antibodies (Abs) with neuropsychiatric lupus (NPSLE), (3) to search for possible mechanisms that are involved in NPSLE, and (4) to determine whether we can recognize a panel of Abs associated with specific neuropsychiatric (NP) manifestations.

METHODS

A MEDLINE search (1975 to 2005) was performed utilizing the following terms: neuropsychiatric lupus, antiphospholipid syndrome, or central nervous system systemic lupus erythematosus matched with the term antibodies.

RESULTS

Twenty Abs (11 brain-specific and 9 systemic) were described in NPSLE patients. These include Abs that target brain-specific antigens (neuronal, ganglioside, synaptosomes, glia, methyl-d-aspartate receptors, lymphocytotoxic) and systemic antigens (nuclear, cytoplasmic, phospholipid, endothelial cells). Cognitive impairment, psychosis, and depression were associated with many Abs. Elevated titers of anticardiolipin Abs (aCL) were reported most often and found in patients with cognitive impairment, psychosis, depression, seizures, chorea, and migraine. No specificity was encountered among brain-specific or systemic Abs for any single NP manifestation. No studies evaluated a specific NP manifestation with the full panel of 20 Abs. A panel of brain-specific and systemic Abs may be helpful in establishing the diagnosis of NPSLE. Postulated mechanisms in experimental models included vascular occlusion and injury by pathogenic Abs in a disrupted blood brain barrier.

CONCLUSIONS

NPSLE is associated with brain-specific and systemic Abs. Cognitive impairment, psychosis, and depression were associated with many Abs, including aCL Abs. Possible mechanisms include vascular occlusion and injury by pathogenic Abs in a disrupted blood brain barrier.

Fine specificity of antibodies against phospholipids and beta-2-glycoprotein I in monoclonal gammopathy associated neuropathies

Phospholipids are abundantly represented within the nervous system. Aim of our study was to evaluate the presence and fine specificity of anti phospholipid antibodies (aPLAb) among patients with monoclonal gammopathy associated neuropathy. Thirty nine percent of these patients had high titers of aPLAb, mostly associated with low levels of anti beta2 glycoprotein I, which suggests different antibody specificity compared to patients with anti phospholipid syndrome. Further 6/48 patients with dysimmune neuropathy without monoclonal gammopathy had positive aPLAb titers. APLAb strongly cross-reacted with sulfatide. These findings suggest an adjuntive role of aPLAb on nerve damage and may help to better understand the nerve binding properties of anti-sulfatide antibodies.

G protein-coupled receptor systems and their lipid environment in health disorders during aging

Cells, tissues and organs undergo phenotypic changes and deteriorate as they age. Cell growth arrest and hyporesponsiveness to extrinsic stimuli are all hallmarks of senescent cells. Most such external stimuli received by a cell are processed by two different cell membrane systems: receptor tyrosine kinases (RTKs) and G protein-coupled receptors (GPCRs). GPCRs form the largest gene family in the human genome and they are involved in most relevant physiological functions. Given the changes observed in the expression and activity of GPCRs during aging, it is possible that these receptors are directly involved in aging and certain age-related pathologies. On the other hand, both GPCRs and G proteins are associated with the plasma membrane and since lipid-protein interactions regulate their activity, they can both be considered to be sensitive to the lipid environment. Changes in membrane lipid composition and structure have been described in aged cells and furthermore, these membrane changes have been associated with alterations in GPCR mediated signaling in some of the main health disorders in elderly subjects. Although senescence could be considered a physiologic process, not all aging humans develop the same health disorders. Here, we review the involvement of GPCRs and their lipid environment in the development of the major human pathologies associated with aging such as cancer, neurodegenerative disorders and cardiovascular pathologies.

Cerebral Manifestations in the Antiphospholipid (Hughes) Syndrome

The importance of cerebral disease in patients with the Hughes syndrome is now becoming more widely recognized. The range of neuropsychiatric manifestations of APS is comprehensive, and includes focal symptoms attributable to lesions in a specific area of the brain as well as diffuse or global dysfunction. Patients with APS frequently present with strokes and TIA, but a wide spectrum of other neurologic features-also including non thrombotic neurologic syndromes-has been described in association with the presence of aPL. The recognition of APS has had a profound impact on the understanding and management of the treatment of CNS manifestations associated with connective tissue diseases, in particular, SLE. Many patients with focal neurologic manifestations and aPL, who a few years ago would have received high-dose corticosteroids or immunosuppression, are often successfully treated with anticoagulation. In our opinion, testing for aPL may have a major diagnostic and therapeutic impact not only in patients with autoimmune diseases and neuropsychiatric manifestations, but also in young individuals who develop cerebral ischemia, in those with atypical multiple sclerosis, transverse myelitis, and atypical seizures. We would also recommend testing for aPL for young individuals found with multiple hyperintensity lesions on brain MRI in the absence of other possible causes,especially when under the age of 40 years. It is our practice to anticoagulate patients with aPL suffering from cerebral ischemia with a target INR of 3.0 to prevent recurrences. Low-dose aspirin alone (with occasional exceptions)does not seem helpful to prevent recurrent thrombosis in these patients. Our recommendation, once the patient has had a proven thrombosis associated with aPL, is long-term (possibly life-long) warfarin therapy. Oral anti coagulation carries a risk of hemorrhage, but in our experience the risk of serious bleeding in patients with APS and previous thrombosis treated with oral anticoagulation to a target INR of 3.5 was similar to that in groups of patients treated with lower target ratios. Although a double-blind crossover trial comparing low molecular weight heparin with placebo in patients with aPL and chronic headaches did not show a significant difference in the beneficial effect of low molecular weight heparin versus placebo, in our experience selected patients with aPL and neuropsychiatric manifestations such as seizures, severe cognitive dys-function, and intractable headaches unresponsive to conventional treatment may respond to anticoagulant treatment. The neurologic ramifications of Hughes syndrome are extensive, and it behoves clinicians in all specialties to be aware of this syndrome because treatment with anticoagulation may profoundly change the outlook for these patients.

Hughes syndrome, the antiphospholipid syndrome: a new chapter in neurology

The importance of cerebral disease in patients with the antiphospholipid (Hughes) syndrome (APS) is now becoming more widely recognized. The range of neuropsychiatric manifestations of APS is comprehensive and includes focal symptoms attributable to lesions in a specific area of the brain as well as diffuse or global dysfunction. Patients with APS frequently present with strokes and transient ischemic attacks, but a wide spectrum of other neurologic features, also including nonthrombotic neurological syndromes, has been described in association with the presence of antiphospholipid antibodies. In this review, we attempt to highlight the large variety of the neurological features of APS.