Neurofilament light in plasma is a potential biomarker of central nervous system involvement in systemic lupus erythematosus

BACKGROUND: Neuropsychiatric manifestations (NP) are common in systemic lupus erythematosus (SLE). However, the pathophysiological mechanisms are not completely understood. Neurofilament light protein (NfL) is part of the neuronal cytoskeleton. Increased NfL concentrations, reflecting neurodegeneration, is observed in cerebrospinal fluid (CSF) in several neurodegenerative and neuroinflammatory conditions. We aimed to explore if plasma NfL could serve as a biomarker for central nervous system (CNS) involvement in SLE. METHODS: Sixty-seven patients with SLE underwent neurological examination; 52 underwent lumbar puncture, while 62 underwent cerebral magnetic resonance imaging (MRI). We measured selected auto-antibodies and other laboratory variables postulated to have roles in NP pathophysiology in the blood and/or CSF. We used SPM12 software for MRI voxel-based morphometry. RESULTS: Age-adjusted linear regression analyses revealed increased plasma NfL concentrations with increasing creatinine (β = 0.01, p < 0.001) and Q-albumin (β = 0.07, p = 0.008). We observed higher plasma NfL concentrations in patients with a history of seizures (β = 0.57, p = 0.014), impaired motor function (β = 0.36, p = 0.008), increasing disease activity (β = 0.04, p = 0.008), and organ damage (β = 0.10, p = 0.002). Voxel-based morphometry suggested an association between increasing plasma NfL concentrations and the loss of cerebral white matter in the corpus callosum and hippocampal gray matter. CONCLUSION: Increased plasma NfL concentrations were associated with some abnormal neurological, cognitive, and neuroimaging findings. However, plasma NfL was also influenced by other factors, such as damage accrual, creatinine, and Q-albumin, thereby obscuring the interpretation of how plasma NfL reflects CNS involvement. Taken together, NfL in CSF seems a better marker of neuronal injury than plasma NfL in patients with SLE

Neurofilament light is a biomarker of brain involvement in lupus and primary Sjögren's syndrome

Background: To test the hypothesis that neuroflament 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. Methods: In 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. Results: A 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 signifcantly in the model (B 0.04, 95% CI 0.03–0.05, p<0.001). Similar fndings 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. Conclusions: Increased 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 domain

Nitrated nucleosome levels and neuropsychiatric events in systemic lupus erythematosus; a multi-center retrospective case-control study

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesBACKGROUND: In patients with systemic lupus erythematosus (SLE) there is no serological test that will reliably distinguish neuropsychiatric (NP) events due to active SLE from those due to other causes. Previously we showed that serum levels of nitrated nucleosomes (NN) were elevated in a small number of patients with NPSLE. Here we measured serum NN in samples from a larger population of patients with SLE and NP events to see whether elevated serum NN could be a marker for NPSLE. METHODS: We obtained serum samples from patients in the Systemic Lupus International Collaborative Clinics (SLICC) inception cohort. This included 216 patients with NP events and two matched controls with SLE but no NP events for each of these patients. For the NP patients we tested samples taken before, during and after the NP event. RESULTS: Twenty-six patients had events attributed to SLE according to the most stringent SLICC attribution rule. In these patients there was no association between onset of event and elevated serum NN. In 190 patients in whom events were not attributed to SLE by the SLICC rules, median serum NN was elevated at the onset of event (P = 0.006). The predominant clinical features in this group of 190 patients were headache, mood disorders and anxiety. CONCLUSIONS: Serum NN levels rise at the time of an NP event in a proportion of patients with SLE. Further studies are needed to determine the value of serum NN as a biomarker for NPSLE.LUPUS UK Rosetrees Trust Arthritis Research UK Programme Grant National Institute for Health Research (NIHR) University College London Hospitals Biomedical Research Centre Canadian Institutes of Health Research Hanyang University Sandwell and West Birmingham Hospitals National Health Service (NHS) Trust IHR/Wellcome Trust Clinical Research Facility in Birmingham National Institutes of Health (NIH) Singer Family Fund for Lupus Research Arthritis Research UK National Institute for Health Research Manchester Biomedical Research Unit NIHR/Wellcome Trust Manchester Clinical Research Facility Danish Rheumatism Association Novo Nordisk Foundation NIH Department of Education, Universities and Research of the Basque Government Arthritis Research U

Memory Dysfunction in Primary Sjogren's Syndrome Is Associated With Anti-NR2 Antibodies

ObjectiveOur understanding of the etiology and pathogenesis of neuropsychiatric involvement in primary Sjogren'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. MethodsSixty-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. ResultsPatients 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. ConclusionResults 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.651232093217Western Norway Regional Health Authorit