anti-NR2 Antibodies Research Articles

Serum Reactive Antibodies against the N-Methyl-D-Aspartate Receptor NR2 Subunit-Could They Act as Potential Biomarkers?

Synaptic dysfunction and disrupted communication between neuronal and glial cells play an essential role in the underlying mechanisms of multiple sclerosis (MS). Earlier studies have revealed the importance of glutamate receptors, particularly the N-methyl-D-aspartate (NMDA) receptor, in excitotoxicity, leading to abnormal synaptic transmission and damage of neurons. Our study aimed to determine whether antibodies to the NR2 subunit of NMDAR are detected in MS patients and evaluate the correlation between antibody presence and clinical outcome. Furthermore, our focus extended to examine a possible link between NR2 reactivity and anti-coagulant antibody levels as pro-inflammatory molecules associated with MS. A cross-sectional study was carried out, including 95 patients with MS and 61 age- and gender-matched healthy controls (HCs). The enzyme-linked immunosorbent assay was used to detect anti-NR2 antibodies in serum samples of participants along with IgG antibodies against factor (F)VIIa, thrombin, prothrombin, FXa, and plasmin. According to our results, significantly elevated levels of anti-NR2 antibodies were detected in MS patients compared to HCs (p < 0.05), and this holds true when we compared the Relapsing-Remitting MS course with HCs (p < 0.05). A monotonically increasing correlation was found between NR2 seropositivity and advanced disability (rs = 0.30; p < 0.01), anti-NR2 antibodies and disease worsening (rs = 0.24; p < 0.05), as well as between antibody activity against NR2 and thrombin (rs = 0.33; p < 0.01). The presence of anti-NR2 antibodies in MS patients was less associated with anti-plasmin IgG antibodies [OR:0.96 (95%CI: 0.92-0.99); p < 0.05]; however, such an association was not demonstrated when analyzing only RRMS patients. In view of our findings, NR2-reactive antibodies may play, paving the way for further research into their potential as biomarkers and therapeutic targets in MS.

Effect of anti-P ribosomal and anti-NR2 antibodies on depression and cognitive processes in SLE: an integrated clinical and functional MRI study

ObjectivesTo explore the effects of anti-ribosomal P protein (anti-P) and anti-N-methyl-D-aspartic acid receptor subunit 2 (anti-NR2) autoantibodies on depression and cognitive dysfunction and their relationships with functional brain connectivity in...

NMDA Receptors in Health and Diseases: New Roles and Signaling Pathways-Anti-N-Methyl-D-Aspartate Receptor (NMDAR) Autoantibodies as Potential Biomarkers of Fatigue in Patients with Rheumatic Diseases.

Fatigue is a widespread and complex symptom with motor and cognitive components; it is diagnosed predominantly by questionnaire. We recently published a correlation between anti-N-methyl-D-aspartate receptor (NMDAR) antibodies and fatigue in patients with SLE (systemic lupus erythematosus). In the present study, we examined whether this association also applies to patients with other rheumatic diseases. Serum samples of 88 patients with different rheumatic diseases were analyzed for the presence of anti-NR2 antibodies and Neurofilament light chain (NfL) protein. The severity of fatigue was determined according to the FSMC questionnaire (Fatigue Scale for Motor and Cognitive Functions) and correlated with the circulating antibody titer and NfL level accordingly. Positive titers of anti-NR2 antibodies were detected in patients with both autoimmune and non-autoimmune rheumatic diseases. These patients suffer predominantly from severe fatigue. The circulating NfL level did not correlate with the anti-NR2 titer and the fatigue severity in all patient groups. The association of severe fatigue with circulating anti-NR2 antibodies in patients with rheumatic diseases, independently from the main disease, suggests an individual role of these autoantibodies in fatigue pathophysiology. Thus, the detection of these autoantibodies might be a helpful diagnostic tool in rheumatic patients with fatigue.

Levels of Neurospecific Peptides, Neurotransmitters and Neuroreceptor Markers in the Serum of Children with Various Sensory Disorders, Mild Cognitive Impairments and Other Neuropathology

Background. The role of recently discovered neurospecific peptides in the pathogenesis of acute and progressive neurologic disorders, their neuroprotective features, and possibilities to use them as markers for the course and prognosis of certain diseases have been actively studied in recent decades. However, neurospecific peptides are almost not studied in chronic residual diseases. In our study we measured the levels of neurospecific peptides and some other markers to achieve understanding of general neurophysiological trends in congenital and acquired chronic non-progressive brain pathology with reference to the selection of relevant groups — study objects. Objective. The aim of the study is to study patterns of neurospecific peptides, neurotransmitters and neuroreceptor markers distribution in the serum of children with various pathogenetic variants of chronic neuropathology. Methods. The study included children from 3 to 16 years old with different pathologies. The sample was divided into groups by pathology type: no sensory and neurological disorders, congenital sensory deficit due to mutation of genes expressed and not expressed in the brain, early acquired sensory deficit of multifactorial nature, congenital mild and severe organic disorders of central nervous system (CNS) in residual stage without baseline sensory deficit, acquired functional CNS disorders without baseline organic defect and sensory deficit. The following laboratory data (neurophysiological components) was studied: nerve growth factor, brain-derived neurotropic factor, neurotrophin-3, neurotrophin-4, neuregulin-1-beta-1, beta-secretase, sirtuin-1, synaptophysin, neuronal nitric oxide synthase, and anti-NR2 glutamate receptor antibodies. The parameters of cognitive activity, sense of vision, sense of smell, and acoustic sense were also evaluated. Results. The study included 274 participants. Neuropeptides and markers have shown a variable degree and range in the group spectrum of differences from normal levels. The most variable in the examined sample was NO-synthase, as well as levels of both neurotrophins, beta-secretase, and glutamate receptor marker. All visual deficits were associated with increased NO-synthase levels (p &lt; 0.001). Neuroplasticity peptides (beta-secretase, neurotrophin-3 and 4) have been activated in all pathological conditions. Nerve growth factor and brain-derived neurotropic factor were specifically activated in mild organic CNS lesions (mild cognitive impairments), while neuregulin — in congenital genetically determined visual deficits. There was no specific activation of neuropeptides and NO-synthase level tended to decrease in cases of severe CNS lesions. Conclusion. The study results suggest that all types of early visual impairment are associated with increased physiological neuronal activity, and non-organic neurological functional disorders — mainly with increased physiological synaptic activity. General neuroplasticity processes were activated in all cases of visual deficits but more specific. However, more specific and well-studied processes were activated in mild organic CNS lesions, and neuroplasticity processes did not activate adequately in severe organic CNS lesions probably due to the limited neuronal and synaptic resources.

Neurofilament light is a biomarker of brain involvement in lupus and primary Sj\xf6gren\u2019s syndrome

BackgroundTo test the hypothesis that neurofilament light (NfL) in CSF is a biomarker of CNS involvement in patients with systemic lupus erythematosus (SLE) and primary Sjögren’s syndrome (pSS), we measured NfL in CSF from 52 patients with lupus and 54 with pSS and explored associations with clinical, structural, immunological and biochemical abnormalities.MethodsIn CSF, we measured NfL, anti-P antibodies, protein S100B and TWEAK by ELISA and anti-NR2 antibodies by electrochemiluminescence. Anti-phospholipid antibodies and routine immunological tests were performed in blood. IgG and albumin were measured in CSF and serum for assessment of the blood–brain barrier function (Q-albumin) and intrathecal IgG production (IgG index). Cerebral MRI and neuropsychological testing were performed.ResultsA multivariable regression model showed that increasing CSF anti-NR2 antibody levels were associated with increasing NfL levels in patients with SLE (B 1.27, 95% CI 0.88–1.65, p < 0.001). Age contributed significantly in the model (B 0.04, 95% CI 0.03–0.05, p < 0.001). Similar findings were observed in the pSS group. Adjusted for age and sex, no associations were found between NfL levels and any MRI data. In SLE patients, higher NfL concentrations were associated with impairments in psychomotor speed and motor function, and in pSS with motor dysfunction. These associations remained in multivariable regression models.ConclusionsIncreased concentration of NfL in CSF is a marker of cerebral involvement in patients with SLE and pSS, is strongly associated with the presence of anti-NR2 antibodies, and correlates with cognitive impairment in several domains.

Association of anti-NR2 and U1RNP antibodies with neurotoxic inflammatory mediators in cerebrospinal fluid from patients with neuropsychiatric systemic lupus erythematosus

Autoantibodies (auto Abs) and inflammatory mediators (IMs) in cerebrospinal fluid (CSF) may be involved in the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE). It is suggested that anti-N-methyl D-aspartate receptor NR2 subunit (NR2) Ab can develop NP manifestation after blood-brain barrier (BBB) abruption. We also reported the association between NPSLE and CSF anti-U1RNP Ab. In the present study, combined effects of CSF anti-NR2 and anti-U1RNP Abs on IMs in patients with NPSLE were examined. CSF samples were collected from 69 patients with NPSLE and 13 non-NPSLE controls. CSF anti-NR2 and anti-U1RNP Abs were determined using ELISA. Levels of IL-6, IL-8, and monokine induced by IFN-γ (MIG) in CSF were measured by quantitative multiplex cytokine analysis. CSF IL-6 levels were higher in CSF anti-NR2-positive than in CSF anti-NR2-negative patients (p = 0.003) and non-NPSLE controls (p = 0.015) and were positively correlated with anti-NR2 titer (r = 0.42). CSF IL-8 levels were higher in CSF anti-U1RNP-positive than in CSF anti-U1RNP-negative patients (p = 0.041). CSF MIG levels were more elevated in CSF anti-NR2-positive (p = 0.043) and anti-U1RNP-positive patients (p = 0.029) than in non-NPSLE controls. Additionally, in double positive (DP; both anti-NR2 and U1RNP Ab positive) group, CSF IL-6 and MIG levels were significantly higher than in the double negative (DN; both anti-NR2 and U1RNP Ab negative) group. However, combined effect of both Abs on IM elevation and clinical manifestation was not clear. CSF anti-NR2 and anti-U1RNP Abs have different effects on the elevation of CSF IM levels in patients with NPSLE. Additional effect of anti-U1RNP Abs on anti-NR2 Ab-mediated NP manifestation, however, was not recognized in our study.

Differential expression of antibodies to NMDA receptor in anti-NMDA receptor encephalitis and in neuropsychiatric systemic lupus erythematosus

ObjectiveAnti-NMDA receptor encephalitis is the most prevalent autoimmune encephalitis having characteristic clinical features with autoantibodies against tetrameric transmembrane channels composed of combinations of NR1 subunits of NMDA receptors with NR2...

Fatigue in SLE: diagnostic and pathogenic impact of anti-N-methyl-D-aspartate receptor (NMDAR) autoantibodies

ObjectivesWe explored the impact of circulating anti-N-methyl-D-aspartate receptor (NMDAR) antibodies on the severity of fatigue in patients with systemic lupus erythematosus (SLE).MethodsSerum samples of 426 patients with SLE were analysed...

Anti-N-Methyl-D-Aspartic Acid Receptor 2 (Anti-NR2) Antibody in Neuropsychiatric Lupus Serum Damages the Blood-Brain Barrier and Enters the Brain.

BackgroundBrain microvessel endothelial cells constitute an important component in the blood-brain barrier. Cell-culture-based models of the blood-brain barrier (BBB) have been extensively applied in pharmacology, pathology and physiology. This study investigated effects of anti-N-methyl-D-aspartic acid receptor 2 (anti-NR2), N-methyl-D-aspartic acid (NMDA) receptor antibodies, NMDA receptor antagonists, and NMDA receptor agonists on brain microvessel endothelial cell models, and verified the effect of anti-NR2 antibody on the BBB as a receptor agonist.Material/MethodsThe primary brain microvessel endothelial cells were isolated and cultured, and an in vitro BBB model was established based on microvessel endothelial cells. Anti-NR2 antibody, glutamic acid, ifenprodil, and memantine were added in the BBB model to analyze changes in transepithelial electrical resistance (TEER) and to examine the permeability of the brain microvessel endothelial cell model.ResultsThe results showed that TEER values were significantly decreased by the addition of anti-NR2 antibody and glutamate, but were significantly increased by the addition of ifenprodil and memantine. TEER values showed no changes when treated by anti-NR2 antibody and ifenprodil, as well as anti-NR2 antibody and memantine. When dexamethasone was added, the TEER values increased by 23.8%, 39.4%, and 29.6% by treating with anti-NR2 antibody, positive cerebrospinal fluid, and positive serum, respectively.ConclusionsOur findings show that anti-NR2 antibody in neuropsychiatric lupus serum can damage the BBB and enter the brain.

The blood–brain barrier, TWEAK, and neuropsychiatric involvement in human systemic lupus erythematosus and primary Sjögren’s syndrome

A prevailing hypothesis for neuropsychiatric involvement in systemic lupus erythematosus (SLE) and primary Sjögren's syndrome is that brain reactive autoantibodies enter the brain through a disrupted blood-brain barrier. Our aim was to investigate whether TNF-like weak inducer of apoptosis (TWEAK) plays a role in cerebral involvement in human SLE and primary Sjögren's syndrome, and whether an impaired blood-brain barrier is a prerequisite for neuropsychiatric manifestations. TWEAK was measured in the cerebrospinal fluid and serum and compared with markers of blood-brain barrier permeability (Q-albumin and MRI contrast-enhanced lesions) and S100B, an astrocyte activation marker in 50 SLE and 52 primary Sjögren's syndrome patients. Furthermore, we estimated the general intrathecal B-cell activation (IgG index), measured anti-NR2 antibodies in cerebrospinal fluid, and explored whether these variables were associated with neuropsychiatric manifestations. No associations were found between TWEAK in the cerebrospinal fluid or serum and neuropsychiatric manifestations in SLE nor in primary Sjögren's syndrome patients. Furthermore, no associations were found between neuropsychiatric manifestations and indicators of blood-brain barrier integrity or astroglial activity. Anti-NR2 antibodies were associated with impaired visuospatial processing (odds ratio 4.9, P = 0.03) and motor functioning (odds ratio 6.0, P = 0.006). No clinical neuropsychiatric manifestations could be attributed to impaired integrity of the blood-brain barrier, or to TWEAK levels in cerebrospinal fluid or serum in either patient group. The TWEAK concentration was considerably higher in the cerebrospinal fluid than in blood, which indicates intrathecal production. We hypothesize that increased TWEAK and S100B result from immunological stress caused by brain-reactive antibodies produced by brain residing immune cells.

Anti-NR2 antibodies, blood-brain barrier, and cognitive dysfunction.

Cognitive dysfunction (CD) is one of the most common neuropsychiatric manifestations of systemic lupus erythematosus (SLE). In animal models, antibodies to NR2 subunit of N-methyl D-aspartate receptor (anti-NR2) cause memory impairment, but only with blood-brain barrier (BBB) disruption or intrathecal administration. Several studies have failed to find association of aNR2 with CD, but none have assessed BBB integrity. S100B, an astrocyte-specific protein, has been used as biomarker of BBB disruption in traumatic brain injury and some neurodegenerative disorders. Antibodies to this immunologically privileged protein (anti-S100B) might indicate preceding BBB disruption. We hypothesized that aNR2 antibody is pathogenic in SLE patients only with BBB disruption. Demographic, clinical, and laboratory data was collected from patients with SLE. Total throughput score (TTS) of the Automated Neuropsychological Assessment Metrics (ANAM) was used as primary outcome measure. CD was defined as TTS < 1.5 SD below an age-, sex-, and race-matched RA population mean. Serum was analyzed by established ELISA techniques. Fifty-seven patients were evaluated and 12 had CD. Age, ethnicity, and family income were significantly different between the two groups (p < 0.05). In a multiple regression model adjusting for other variables, no significant effects of anti-NR2, S100B, or anti-S100B on TTS were found. Even at high levels of S100B and anti-S100B, no significant influence of anti-NR2 on TTS was found. The anti-NR2 was not associated with CD in SLE even in context of potential BBB disruption. This suggests that, if pathogenic, these antibodies may be produced intrathecally.

Abstract WP256: Serum Glutamate Level but Not NMDAR Antibody - A Potential Biomarker of Early Ischemia in Rat Stroke Model

Introduction: Identifying a biomarker for early detection of ischemia is indispensable as millions of stroke patients are in dire need of a screening tool that is fast in diagnosis whilst obviating the need of expensive neuroimages. Hypothesis: A key element in ischaemic cascade is the failure of energy dependent ion channels that leads to influx of calcium ions. This influx triggers multifold release of Glutamate - an Excitatory Neurotransmitter that activates NMDA receptor which further augments the spread of depolarization from ischaemic core to the viable penumbra. We assessed the hypothesis that Glutamate is a credible early biomarker of ischaemic insult to the brain. This proposition was trialed on an animal stroke model. Methods: The stroke model was created through permanent Middle Cerebral Artery Occlusion(pMCAO) on 39 male Wistar Albino rats (250-300g). The rats were divided into Stroke group(n 24) and Sham/Control group(n 15). The blood samples were collected 0 hour (before stroke induction/sham procedure) and also at 1, 3 or 6 hours post procedure. The serum was tested for Glutamate and anti-NR2 Antibody using ELISA assay. Results: Serum Glutamate increased 4-fold at 1 hour of stroke induction (from 0.24+0.3nmol to 3.7+0.8nmol(p&lt;0.0001))(Fig. 1A). No significant difference in Glutamate levels were observed between two groups at 3 or 6 hour(Fig. 1B &amp; 1C). Serum Glutamate of Stroke rats at 3 different time-point showed that it can be detected as early as 1 hour of stroke induction but plummets to pre-stroke level at 3 to 6 hours(Fig. 2). The levels of anti-NR2 antibody were below detectable limits in both Stroke and Sham Control rats throughout the experiments. Conclusions: Serum Glutamate level rose significantly within 1 hour of stroke in our rat pMCAO model, but no detectable antibody was obtained for NR2 subunit of NMDAR indicating delay in antibody formation. Translational research can validate Glutamate as marker of early ischaemia. ischaemia.

Migraine in patients with systemic lupus erythematosus is associated with reduced cerebral grey matter volume but not with measures of glial activation or anti-NR2 or anti-P antibodies.

Migraine is frequent in patients with systemic lupus erythematosus (SLE), but the pathogenesis and pathophysiology are poorly understood. Migraine is assumed to be a consequence of abnormal neuronal excitability. Based on the hypothesis that the threshold for migraine is lower in SLE patients due to cerebral disturbances, whether structural abnormalities of the brain or relevant biomarkers are associated with headaches in SLE was investigated. Sixty-seven SLE patients and age- and gender-matched healthy subjects participated. Volumes of grey matter (GM) and white matter (WM) were estimated from cerebral magnetic resonance images with SPM8 software. Anti-NR2 and anti-P antibodies and protein S100B were measured in cerebrospinal fluid. In regression analyses, larger GM volumes in SLE patients reduced the odds for headache in general [odds ratio (OR) 0.98, P = 0.048] and for migraine in particular (OR 0.95, P = 0.004). No localized loss of GM was observed. Larger WM volumes in patients increased the odds for migraine (OR 1.04, P = 0.007). These findings could not be confirmed in healthy subjects. Neither anti-NR2 and anti-P antibodies nor S100B were associated with headaches in SLE patients. Systemic lupus erythematosus patients with migraine have a diffuse reduction in GM compared to patients without migraine. This finding was not observed in healthy subjects with migraine, and selected biomarkers did not indicate specific pathophysiological processes in the brain. These findings indicate that unknown pathogenic processes are responsible for the increased frequency of migraine in SLE patients.

Pathogenesis of Neuropsychiatric Syndromes of Systemic Lupus Erythematosus

The pathogenesis of neuropsychiatric syndromes of systemic lupus erythematosus (NPSLE) is multifactorial and can involve various inflammatory cytokines, autoantibodies such as anti-neuronal antibodies, anti-ribosomal P antibodies, anti-NR2 glutamate receptor binding antibodies, anti-Sm antibodies, anti-U1-RNP antibodies and anti-phospholipid antibodies, and immune complexes (IC). Disruption of the blood-brain barrier (BBB) is integral to the neuropathology of SLE. Recently the possibility has been reported that aforementioned autoantibodies in the circulation may be strongly associated with disruption of the BBB. Each of these mechanisms might contribute to the pathogenesis of focal NPSLE (for example, cerebrovascular disease, movement disorders, myelopathy, seizures and cranial neuropathy) or diffuse NPSLE (for example, acute confusional state, psychosis and cognitive dysfunction) to varying degrees. In this review we focus on how the aforementioned autoantibodies, the BBB, IC and cytokines as well as chemokines are associated with the appearance of NPSLE.

Association of hippocampal atrophy with cerebrospinal fluid antibodies against the NR2 subtype of the N-methyl-D-aspartate receptor in patients with systemic lupus erythematosus and patients with primary Sjögren's syndrome.

Cognitive dysfunction is common in both systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (SS). Antibodies against the NR2 subtype of the N-methyl-D-aspartate receptor (anti-NR2 antibodies) cause hippocampal atrophy and cognitive impairment in mice and have been associated with memory impairment in both patients with SLE and patients with primary SS. In addition, a reduced volume of hippocampal gray matter has been demonstrated in both SLE and primary SS. This study was undertaken to investigate whether there is a connection between the presence of anti-NR2 antibodies and hippocampal atrophy in human diseases. Fifty patients with SLE and 50 patients with primary SS underwent clinical examination and cerebral magnetic resonance imaging. Anti-NR2 antibodies in cerebrospinal fluid (CSF) were measured, and hippocampal gray matter volumes were compared between patients who were positive for and those who were negative for anti-NR2 antibodies. Patients with anti-NR2 antibodies in CSF had less hippocampal gray matter than patients without these antibodies. No other differences regarding gray matter volumes in other parts of the brain were identified. The present findings indicate that anti-NR2 antibodies in patients with SLE and primary SS cause neuronal death manifested as reduced hippocampal gray matter, as has been previously demonstrated in mice with autoimmune disease.

FRI0397 Relationship between Igg Anti-Nr2 Glutamate Receptor Antibodies and Depressive/Anxiety Symptoms in Patients with Systemic Lupus Erythematosus

ObjectivesTo study the relationship between anti-NR2 glutamate receptor antibodies (anti-NR2) and depressive/anxiety symptoms in patients with systemic lupus erythematosus (SLE).MethodsConsecutive Chinese patients who fulfilled ≥4 ACR criteria for SLE were...

Impact analysis of autoantibody level and NR2 antibody level in neuropsychiatric SLE treated by methylprednisolone combined with MTX and DXM intrathecal injection.

The objective is to explore the clinical curative effects of methylprednisolone combined with MTX and DXM intrathecal injection in treating neuropsychiatric systemic lupus erythematosus (NPSLE) and its effects on autoantibody level and anti-N-methyl-D-aspartate receptor subtype NR2a/2b antibody (anti-NR2 antibody) level. Thirty six admitted NPSLE patients were treated by methylprednisolone combined with MTX and DXM intrathecal injection. Thirty six SLE patients without neuropsychiatric symptoms were selected as non-NPSLE group. Clinical indexes including SLE activity index, erythrocyte sedimentation rate (ESR), cerebrospinal fluid pressure (CSFP), cerebrospinal fluid protein were observed before and after treatment. Autoantibodies including anti-nuclear antibody (ANA), anti-double stranded DNA antibody (anti-dsDNA antibody), anti-extractable nuclear antigen antibody (ENA-Ab) were detected before and after treatment. Enzyme linked immunosorbent assay was used to detect NR2 antibody level before and after treatment in two groups. Upon treatment of methylprednisolone combined with MTX and DXM intrathecal injection, SLE activity index, ESR, CSFP, cerebrospinal fluid protein of 36 NPSLE patients were significantly decreased. Before treatment, positive rates of ANA, anti-dsDNA antibody, and anti-ENA antibody in both NPSLE group and non-NPSLE group had no significant difference. However, positive rate of anti-NR2 antibody in NPSLE group was significantly higher than that of non-NPSLE group. After treatment, positive rates of autoantibodies and anti-NR2 antibody in both NPSLE and non-NPSLE group were significantly decreased. Anti-NR2 antibody can be a screening index of NPSLE, and methylprednisolone combined with MTX and DXM intrathecal injection has significant curative effects and can effectively decrease autoantibody level and anti-NR2 antibody level.

Memory Dysfunction in Primary Sjögren's Syndrome Is Associated With Anti‐NR2 Antibodies

Our understanding of the etiology and pathogenesis of neuropsychiatric involvement in primary Sjögren's syndrome (SS) is incomplete. In systemic lupus erythematosus, it has been reported that antibodies directed against N-methyl-D-aspartate receptor subtype NR2 (anti-NR2) interfere with memory and learning function, as well as mood. This has not been investigated in primary SS; however, the present study was undertaken to advance our understanding of neuropsychiatric involvement in this disease. Sixty-six patients with primary SS and 66 age- and sex-matched healthy control subjects underwent clinical examination and neuropsychological evaluation. Anti-NR2 antibodies were measured in serum and cerebrospinal fluid. Hippocampus volume was estimated using software extensions to SPM5. Patients with primary SS had smaller hippocampi than healthy subjects (mean ± SD 8.15 ± 0.98 cm(3) versus 8.49 ± 0.88 cm(3); P = 0.01). In patients with primary SS, anti-NR2 antibodies in cerebrospinal fluid were associated with a worse performance in 8 of 10 memory and learning tests, and anti-NR2 antibodies in serum were associated with a worse performance in 6 of those same tests. In addition, a higher proportion of patients with depression than patients without depression had serum anti-NR2 antibody levels above the cutoff value. Results of this study indicate that anti-NR2 antibodies may represent one of the pathogenetic mechanisms for cognitive disturbances and mood disorders in patients with primary SS.

THU0291 Serum Anti-NR2 Alone is not an Ideal Marker of Subclinical Working Memory and Learning Deficits Assessed Based on Abnormal Real-Time Functional Brain Signals in Systemic Lupus Erythematosus

BackgroundSince the N-methyl-D-aspartate receptors (NMDARs) are most densely populated in the hippocampi and amygdala and are involved in mediating learning and working memory, the discordant activities in the hippocampus and...

OP0061 Seizures in systemic lupus erythematosus: A prospective study of predictors and outcomes in a large, international, disease inception cohort

BackgroundSeizures are a manifestation of neuropsychiatric (NP) SLE and occur in 6% to 51% of adult and pediatric patients.ObjectivesTo describe the frequency, attribution and outcome of seizure disorders and to...