Deterministic programming of human pluripotent stem cells into microglia facilitates studying their role in health and disease.

Microglia, the resident immune cells of the central nervous system (CNS), are derived from yolk-sac macrophages that populate the developing CNS during early embryonic development. Once established, the microglia population is self-maintained throughout life by local proliferation. As a scalable source of microglia-like cells (MGLs), we here present a forward programming protocol for their generation from human pluripotent stem cells (hPSCs). The transient overexpression of PU.1 and C/EBPß in hPSCs led to a homogenous population of mature microglia within 16 d. MGLs met microglia characteristics on a morphological, transcriptional, and functional level. MGLs facilitated the investigation of a human tauopathy model in cortical neuron-microglia cocultures, revealing a secondary dystrophic microglia phenotype. Single-cell RNA sequencing of microglia integrated into hPSC-derived cortical brain organoids demonstrated a shift of microglia signatures toward a more-developmental in vivo-like phenotype, inducing intercellular interactions promoting neurogenesis and arborization. Taken together, our microglia forward programming platform represents a tool for both reductionist studies in monocultures and complex coculture systems, including 3D brain organoids for the study of cellular interactions in healthy or diseased environments.

A genome-wide association study in autoimmune neurological syndromes with anti-GAD65 autoantibodies.

Autoimmune neurological syndromes (AINS) with autoantibodies against the 65 kDa isoform of the glutamic acid decarboxylase (GAD65) present with limbic encephalitis, including temporal lobe seizures or epilepsy, cerebellitis with ataxia, and stiff-person-syndrome or overlap forms. Anti-GAD65 autoantibodies are also detected in autoimmune diabetes mellitus, which has a strong genetic susceptibility conferred by human leukocyte antigen (HLA) and non-HLA genomic regions. We investigated the genetic predisposition in patients with anti-GAD65 AINS. We performed a genome-wide association study (GWAS) and an association analysis of the HLA region in a large German cohort of 1214 individuals. These included 167 patients with anti-GAD65 AINS, recruited by the German Network for Research on Autoimmune Encephalitis (GENERATE), and 1047 individuals without neurological or endocrine disease as population-based controls. Predictions of protein expression changes based on GWAS findings were further explored and validated in the CSF proteome of a virtually independent cohort of 10 patients with GAD65-AINS and 10 controls. Our GWAS identified 16 genome-wide significant (P < 5 × 10-8) loci for the susceptibility to anti-GAD65 AINS. The top variant, rs2535288 [P = 4.42 × 10-16, odds ratio (OR) = 0.26, 95% confidence interval (CI) = 0.187-0.358], localized to an intergenic segment in the middle of the HLA class I region. The great majority of variants in these loci (>90%) mapped to non-coding regions of the genome. Over 40% of the variants have known regulatory functions on the expression of 48 genes in disease relevant cells and tissues, mainly CD4+ T cells and the cerebral cortex. The annotation of epigenomic marks suggested specificity for neural and immune cells. A network analysis of the implicated protein-coding genes highlighted the role of protein kinase C beta (PRKCB) and identified an enrichment of numerous biological pathways participating in immunity and neural function. Analysis of the classical HLA alleles and haplotypes showed no genome-wide significant associations. The strongest associations were found for the DQA1*03:01-DQB1*03:02-DRB1*04:01HLA haplotype (P = 4.39 × 10-4, OR = 2.5, 95%CI = 1.499-4.157) and DRB1*04:01 allele (P = 8.3 × 10-5, OR = 2.4, 95%CI = 1.548-3.682) identified in our cohort. As predicted, the CSF proteome showed differential levels of five proteins (HLA-A/B, C4A, ATG4D and NEO1) of expression quantitative trait loci genes from our GWAS in the CSF proteome of anti-GAD65 AINS. These findings suggest a strong genetic predisposition with direct functional implications for immunity and neural function in anti-GAD65 AINS, mainly conferred by genomic regions outside the classical HLA alleles.

NOX4-derived ROS are neuroprotective by balancing intracellular calcium stores.

Hyperexcitability is associated with neuronal dysfunction, cellular death, and consequently neurodegeneration. Redox disbalance can contribute to hyperexcitation and increased reactive oxygen species (ROS) levels are observed in various neurological diseases. NOX4 is an NADPH oxidase known to produce ROS and might have a regulating function during oxidative stress. We, therefore, aimed to determine the role of NOX4 on neuronal firing, hyperexcitability, and hyperexcitability-induced changes in neural network function. Using a multidimensional approach of an in vivo model of hyperexcitability, proteomic analysis, and cellular function analysis of ROS, mitochondrial integrity, and calcium levels, we demonstrate that NOX4 is neuroprotective by regulating ROS and calcium homeostasis and thereby preventing hyperexcitability and consequently neuronal death. These results implicate NOX4 as a potential redox regulator that is beneficial in hyperexcitability and thereby might have an important role in neurodegeneration.

A novel NMDA receptor test model based on hiPSC-derived neural cells.

N-Methyl-D-aspartate receptors (NMDARs) are central for learning and information processing in the brain. Dysfunction of NMDARs can play a key role in the pathogenesis of neurodegeneration and drug addiction. The development of selective NMDAR modulators represents a promising strategy to target these diseases. Among such modulating compounds are ifenprodil and its 3-benzazepine derivatives. Classically, the effects of these NMDAR modulators have been tested by techniques like two-electrode voltage clamp (TEVC), patch clamp, or fluorescence-based assays. However, testing their functional effects in complex human systems requires more advanced approaches. Here, we established a human induced pluripotent stem cell-derived (hiPSC-derived) neural cell system and proved its eligibility as a test system for investigating NMDAR modulators and pharmaceutical effects on human neurons.

Supply problems of antiseizure medication are common among epilepsy patients in Germany.

OBJECTIVE: To evaluate the frequency of reported antiseizure medication (ASM) supply problems among patients with epilepsy (PWE) in Germany. METHODS: The Epi2020 study was a multicenter study focusing on different healthcare aspects of adult PWE in Germany. In addition to basic clinical and demographic characteristics, PWE were asked to answer a questionnaire regarding supply difficulties regarding their ASM, and if they had to discontinue ASM treatment due to supply problems. Generic switch of medication was recorded, and adverse effects were measured using the Liverpool Adverse Events Profile (LAEP) scale. Data were analyzed to detect predictors of supply problems. RESULTS: In total, 434 PWE with a mean age of 40 years (median 37 years, SD = 15.5, range: 18-83 years, 254 female) participated in this study. 53.7% of PWE (n = 233) reported that at least once in the past 12 months their ASM was not available at the pharmacy, and 24.9% (n = 108) reported having experienced ASM supply problems three times or more during the past 12 months. Patients with epilepsy treated with carbamazepine and zonisamide reported frequent problems with availability in 45.8% and 44.8% respectively, whereas those treated with lacosamide and valproate reported supply problems less frequently (17.0% and 16.4%, respectively). Nine patients (2.1%) were unable to take their ASM as prescribed at least once in the past 12 months due to supply problems. Forty-nine patients (11.3%) reported having to switch ASM due to supply difficulties with generic replacement occurring in 39.4% (n = 171) of patients. Those with supply problems were more likely to be treated with more ASMs and scored higher on the LAEP. CONCLUSION: Supply problems with ASM are frequent among PWE in Germany and are reported for older and newer ASMs. Supply problems contribute to ASM nonadherence and are positively correlated with the number of ASM taken and adverse events.

Unemployment and early retirement among patients with epilepsy - A study on predictors, resilience factors and occupational reintegration measures.

The primary aim of this study was to identify predictors and resilience factors for unemployment and early retirement in patients with epilepsy of working age based on data from a multicenter German cohort study performed in 2020 (n = 456) by using multivariate binary logistic regression analysis. A second aim was to assess the assumed working ability of patients as well as the use of occupational reintegration measures. The unemployment rate was 8.3%, and 18% of patients had retired early due to epilepsy. Multivariate binary logistic regression analysis identified the presence of a relevant disability and frequent seizures as significant predictors of unemployment and early retirement, while seizures in remission were the only resilience factor associated with job retention. Regarding occupational incapacity, at the time of the survey, most of the patients in early retirement or unemployment were fit for work in their original or extended occupational setting. The proportion of patients with recent epilepsy-related occupational retraining (0.4%) or job changes (0.9%) was low, and only 2.4% reported an epilepsy-related reduction in work time. These findings underline the persistent disadvantage of patients with epilepsy in the professional field and the urgent need for effective, comprehensive work reintegration measures that must be made accessible for all patients.

Activation of non-classical NMDA receptors by glycine impairs barrier function of brain endothelial cells.

Blood-brain barrier (BBB) integrity is necessary to maintain homeostasis of the central nervous system (CNS). NMDA receptor (NMDAR) function and expression have been implicated in BBB integrity. However, as evidenced in neuroinflammatory conditions, BBB disruption contributes to immune cell infiltration and propagation of inflammatory pathways. Currently, our understanding of the pathophysiological role of NMDAR signaling on endothelial cells remains incomplete. Thus, we investigated NMDAR function on primary mouse brain microvascular endothelial cells (MBMECs). We detected glycine-responsive NMDAR channels, composed of functional GluN1, GluN2A and GluN3A subunits. Importantly, application of glycine alone, but not glutamate, was sufficient to induce NMDAR-mediated currents and an increase in intracellular Ca2+ concentrations. Functionally, glycine-mediated NMDAR activation leads to loss of BBB integrity and changes in actin distribution. Treatment of oocytes that express NMDARs composed of different subunits, with GluN1 and GluN3A binding site inhibitors, resulted in abrogation of NMDAR signaling as measured by two-electrode voltage clamp (TEVC). This effect was only detected in the presence of the GluN2A subunits, suggesting the latter as prerequisite for pharmacological modulation of NMDARs on brain endothelial cells. Taken together, our findings argue for a novel role of glycine as NMDAR ligand on endothelial cells shaping BBB integrity.

Use of Health-Related Apps and Telehealth in Adults with Epilepsy in Germany: A Multicenter Cohort Study.

Background: Telehealth can improve the treatment of chronic disorders, such as epilepsy. Telehealth prevalence and use increased during the coronavirus disease 2019 (COVID-19) pandemic. However, familiarity with and use of telehealth and health-related mobile applications (apps) by persons with epilepsy remain unknown. Methods: We investigated telehealth use, demographics, and clinical variables within the multicenter Epi2020 cross-sectional study. Between October and December 2020, adults with epilepsy completed a validated questionnaire, including individual questions regarding knowledge and use of apps and telehealth. Results: Of 476 included individuals (58.2% women; mean age 40.2 ± 15.4 years), 41.6% reported using health-related apps. Health apps were used more frequently (pedometer 32.1%, exercise app 17.6%) than medical apps (health insurance 15.1%, menstrual apps 12.2%) or apps designed for epilepsy (medication reminders 10.3%, seizure calendars 4.6%). Few used seizure detectors (i.e., apps as medical devices 1.9%) or mobile health devices (fitness bracelet 11.3%). A majority (60.9%) had heard the term telehealth, 78.6% of whom had a positive view. However, only 28.6% had a concrete idea of telehealth, and only 16.6% reported personal experience with telehealth. A majority (55%) would attend a teleconsultation follow-up, and 41.2% would in a medical emergency. Data privacy and availability were considered equally important by 50.8%, 21.8% considered data privacy more important, and 20.2% considered data availability more important. Current health-related app use was independently associated with younger age (p = 0.003), higher education (p < 0.001), and subjective COVID-19-related challenges (p = 0.002). Persistent seizure occurrence (vs. seizure freedom ≥12 months) did not affect willingness to use teleconsultations on multivariable logistic regression analysis. Conclusions: Despite positive telehealth views, few persons with epilepsy in Germany are familiar with specific apps or services. Socioeconomic factors influence telehealth use more than baseline epilepsy characteristics. Telehealth education and services should target socioeconomically disadvantaged individuals to reduce the digital care gap. German Clinical Trials Register (DRKS00022024; Universal Trial Number: U1111-1252-5331).

A role for TASK2 channels in the human immunological synapse.

The immunological synapse is a transient junction that occurs when the plasma membrane of a T cell comes in close contact with an APC after recognizing a peptide from the antigen-MHC. The interaction starts when CRAC channels embedded in the T cell membrane open, flowing calcium ions into the cell. To counterbalance the ion influx and subsequent depolarization, Kv 1.3 and KCa3.1 channels are recruited to the immunological synapse, increasing the extracellular K+ concentration. These processes are crucial as they initiate gene expression that drives T cell activation and proliferation. The T cell-specific function of the K2P channel family member TASK2 channels and their role in autoimmune processes remains unclear. Using mass spectrometry analysis together with epifluorescence and super-resolution single-molecule localization microscopy, we identified TASK2 channels as novel players recruited to the immunological synapse upon stimulation. TASK2 localizes at the immunological synapse, upon stimulation with CD3 antibodies, likely interacting with these molecules. Our findings suggest that, together with Kv 1.3 and KCa3.1 channels, TASK2 channels contribute to the proper functioning of the immunological synapse, and represent an interesting treatment target for T cell-mediated autoimmune disorders.

Multicenter, cross-sectional study of the costs of illness and cost-driving factors in adult patients with epilepsy.

OBJECTIVE: This study was undertaken to quantify epilepsy-related costs of illness (COI) in Germany and identify cost-driving factors. METHODS: COI were calculated among adults with epilepsy of different etiologies and severities. Multiple regression analysis was applied to determine any epilepsy-related and sociodemographic factors that serve as cost-driving factors. RESULTS: In total, 486 patients were included, with a mean age of 40.5 ± 15.5 years (range = 18-83 years, 58.2% women). Mean 3-month COI were estimated at €4911, €2782, and €2598 for focal, genetic generalized, and unclassified epilepsy, respectively. The mean COI for patients with drug-refractory epilepsy (DRE; €7850) were higher than those for patients with non-DRE (€4720), patients with occasional seizures (€3596), or patients with seizures in remission for >1 year (€2409). Identified cost-driving factors for total COI included relevant disability (unstandardized regression coefficient b = €2218), poorer education (b = €2114), living alone (b = €2612), DRE (b = €1831), and frequent seizures (b = €2385). Younger age groups of 18-24 years (b = -€2945) and 25-34 years (b = -€1418) were found to have lower overall expenditures. A relevant disability (b = €441), DRE (b = €1253), frequent seizures (b = €735), and the need for specialized daycare (b = €749) were associated with higher direct COI, and poorer education (b = €1969), living alone (b = €2612), the presence of a relevant disability (b = €1809), DRE (b = €1831), and frequent seizures (b = €2385) were associated with higher indirect COI. SIGNIFICANCE: This analysis provides up-to-date COI data for use in further health economics analyses, highlighting the high economic impacts associated with disease severity, disability, and disease-related loss of productivity among adult patients with epilepsy. The identified cost drivers could be used as therapeutic and socioeconomic targets for future cost-containment strategies.

Trends in resource utilization and cost of illness in patients with active epilepsy in Germany from 2003 to 2020.

OBJECTIVE: This study was undertaken to calculate epilepsy-related direct, indirect, and total costs in adult patients with active epilepsy (ongoing unprovoked seizures) in Germany and to analyze cost components and dynamics compared to previous studies from 2003, 2008, and 2013. This analysis was part of the Epi2020 study. METHODS: Direct and indirect costs related to epilepsy were calculated with a multicenter survey using an established and validated questionnaire with a bottom-up design and human capital approach over a 3-month period in late 2020. Epilepsy-specific costs in the German health care sector from 2003, 2008, and 2013 were corrected for inflation to allow for a valid comparison. RESULTS: Data on the disease-specific costs for 253 patients in 2020 were analyzed. The mean total costs were calculated at €5551 (±€5805, median = €2611, range = €274-€21 667) per 3 months, comprising mean direct costs of €1861 (±€1905, median = €1276, range = €327-€13 158) and mean indirect costs of €3690 (±€5298, median = €0, range = €0-€11 925). The main direct cost components were hospitalization (42.4%), antiseizure medication (42.2%), and outpatient care (6.2%). Productivity losses due to early retirement (53.6%), part-time work or unemployment (30.8%), and seizure-related off-days (15.6%) were the main reasons for indirect costs. However, compared to 2013, there was no significant increase of direct costs (-10.0%), and indirect costs significantly increased (p < .028, +35.1%), resulting in a significant increase in total epilepsy-related costs (p < .047, +20.2%). Compared to the 2013 study population, a significant increase of cost of illness could be observed (p = .047). SIGNIFICANCE: The present study shows that disease-related costs in adult patients with active epilepsy increased from 2013 to 2020. As direct costs have remained constant, this increase is attributable to an increase in indirect costs. These findings highlight the impact of productivity loss caused by early retirement, unemployment, working time reduction, and seizure-related days off.

Dietary conjugated linoleic acid links reduced intestinal inflammation to amelioration of CNS autoimmunity.

A close interaction between gut immune responses and distant organ-specific autoimmunity including the CNS in multiple sclerosis has been established in recent years. This so-called gut-CNS axis can be shaped by dietary factors, either directly or via indirect modulation of the gut microbiome and its metabolites. Here, we report that dietary supplementation with conjugated linoleic acid, a mixture of linoleic acid isomers, ameliorates CNS autoimmunity in a spontaneous mouse model of multiple sclerosis, accompanied by an attenuation of intestinal barrier dysfunction and inflammation as well as an increase in intestinal myeloid-derived suppressor-like cells. Protective effects of dietary supplementation with conjugated linoleic acid were not abrogated upon microbiota eradication, indicating that the microbiome is dispensable for these conjugated linoleic acid-mediated effects. Instead, we observed a range of direct anti-inflammatory effects of conjugated linoleic acid on murine myeloid cells including an enhanced IL10 production and the capacity to suppress T-cell proliferation. Finally, in a human pilot study in patients with multiple sclerosis (n = 15, under first-line disease-modifying treatment), dietary conjugated linoleic acid-supplementation for 6 months significantly enhanced the anti-inflammatory profiles as well as functional signatures of circulating myeloid cells. Together, our results identify conjugated linoleic acid as a potent modulator of the gut-CNS axis by targeting myeloid cells in the intestine, which in turn control encephalitogenic T-cell responses.

Dimethyl fumarate treatment restrains the antioxidative capacity of T cells to control autoimmunity.

Dimethyl fumarate, an approved treatment for relapsing-remitting multiple sclerosis, exerts pleiotropic effects on immune cells as well as CNS resident cells. Here, we show that dimethyl fumarate exerts a profound alteration of the metabolic profile of human CD4+ as well as CD8+ T cells and restricts their antioxidative capacities by decreasing intracellular levels of the reactive oxygen species scavenger glutathione. This causes an increase in mitochondrial reactive oxygen species levels accompanied by an enhanced mitochondrial stress response, ultimately leading to impaired mitochondrial function. Enhanced mitochondrial reactive oxygen species levels not only result in enhanced T-cell apoptosis in vitro as well as in dimethyl fumarate-treated patients, but are key for the well-known immunomodulatory effects of dimethyl fumarate both in vitro and in an animal model of multiple sclerosis, i.e. experimental autoimmune encephalomyelitis. Indeed, dimethyl fumarate immune-modulatory effects on T cells were completely abrogated by pharmacological interference of mitochondrial reactive oxygen species production. These data shed new light on dimethyl fumarate as bona fide immune-metabolic drug that targets the intracellular stress response in activated T cells, thereby restricting mitochondrial function and energetic capacity, providing novel insight into the role of oxidative stress in modulating cellular immune responses and T cell-mediated autoimmunity.

Trends in antiseizure medication prescription patterns among all adults, women, and older adults with epilepsy: A German longitudinal analysis from 2008 to 2020.

INTRODUCTION: The prescription patterns of antiseizure medication (ASM) are subject to new scientific evidence and sociodemographic and practical aspects. This study analyzed trends in ASM prescription patterns among all adults with epilepsy, with special consideration for women of childbearing potential (WOCBP) and older adult (≥65 years old) patients. METHODS: Data from four questionnaire-based cohort studies, conducted in 2008, 2013, 2016, and 2020, were analyzed for ASM prescription frequencies and common mono- and dual therapy regimens. Statistical comparisons were performed with the Chi-square test and one-way analysis of variance. RESULTS: Overall, the individual prescription patterns among 1,642 adult patients with epilepsy were analyzed. A significant increase in the prescription frequency of third-generation ASMs, from 59.3% to 84.2% (p = 0.004), was accompanied by a decrease in the frequency of first- and second-generation ASMs (5.4% to 2.1% and 34.9% to 12.6%, respectively). This trend was accompanied by a significant decrease in the use of enzyme-inducing ASMs, from 23.9% to 4.6% (p = 0.004). Among frequently prescribed ASMs, prescriptions of carbamazepine (18.6% to 3.1%, p = 0.004) and valproate (15.4% to 8.7%, p = 0.004) decreased, whereas prescriptions of levetiracetam (18.0% up to 32.4%, p = 0.004) increased significantly. The prescription frequency of lamotrigine remained largely constant at approximately 20% (p = 0.859). Among WOCBP, the prescription frequencies of carbamazepine (11.4% to 2.0%, p = 0.004) and valproate (16.1% to 6.1%, p = 0.004) decreased significantly. Levetiracetam monotherapy prescriptions increased significantly (6.6% to 30.4%, p = 0.004) for WOCBP, whereas lamotrigine prescriptions remained consistent (37.7% to 44.9%, p = 0.911). Among older adult patients, a significant decrease in carbamazepine prescriptions (30.1% to 7.8%, p = 0.025) was the only relevant change in ASM regimens between 2008 and 2020. In patients with genetic generalized epilepsies, levetiracetam was frequently used as an off-label monotherapy (25.0% to 35.3%). CONCLUSION: These results show a clear trend toward the use of newer and less interacting third-generation ASMs, with lamotrigine, levetiracetam, and lacosamide representing the current ASMs of choice, displacing valproate and carbamazepine over the last decade. In WOCBP, prescription patterns shifted to minimize teratogenic effects, whereas, among older adults, the decrease in carbamazepine use may reflect the avoidance of hyponatremia risks and attempts to reduce the interaction potential with other drugs and ASMs. Levetiracetam is frequently used off-label as a monotherapy in patients with genetic generalized epilepsy.

Determinants of cognition in autoimmune limbic encephalitis-A retrospective cohort study.

Autoimmune limbic encephalitis (ALE) is the most common type of autoimmune encephalitis (AIE). Subacute memory disturbance, temporal lobe seizures, and psychiatric symptoms are clinical hallmarks of the disease. However, little is known on the factors contributing to cognitive functioning in ALE. Hence, we here investigate major determinants of cognitive functioning in ALE. In a retrospective analysis of 102 patients with ALE, we first compared verbal learning capacity, nonverbal learning capacity, and attentional and executive functioning by absence or presence of different types of neural autoantibodies (AABs). Subsequently we established three linear regression models including 63, 38, and 61 patients, respectively to investigate how cognitive functioning in these domains may depend on common markers of ALE such as intrathecal inflammation, blood-cerebrospinal fluid (CSF)-barrier function, mesiotemporal epileptiform discharges and slowing, determined by electroencephalography (EEG) and structural mesiotemporal changes, measured with magnetic resonance imaging (MRI). We also accounted for possible effects of cancer- and immunotherapy and other centrally effective medication. There was no effect of AAB status on cognitive functioning. Although the regression models could not predict verbal and nonverbal learning capacity, structural mesiotemporal neural network alterations on T2-/fluid attenuated inversion recovery (FLAIR)-signal-weighted MRI and mesiotemporal epileptiform discharges or slowing on EEG exerted a significant impact on memory functions. In contrast, the regression model significantly predicted attentional and executive functioning with CSF white blood cell count and centrally effective medication being significant determinants. In this cohort, cognitive functioning in ALE does not depend on the AAB status. Common markers of ALE cannot predict memory functioning that only partially depends on structural and functional alterations of mesiotemporal neural networks. Common markers of ALE significantly predict attentional and executive functioning that is significantly related to centrally effective medication and CSF white blood cell count, which may point toward inflammation affecting brain regions beyond the limbic system.

Long-term efficacy, tolerability, and retention of brivaracetam in epilepsy treatment: A longitudinal multicenter study with up to 5 years of follow-up.

OBJECTIVE: This study was undertaken to evaluate the long-term efficacy, retention, and tolerability of add-on brivaracetam (BRV) in clinical practice. METHODS: A multicenter, retrospective cohort study recruited all patients who initiated BRV between February and November 2016, with observation until February 2021. RESULTS: Long-term data for 262 patients (mean age = 40 years, range = 5-81 years, 129 men) were analyzed, including 227 (87%) diagnosed with focal epilepsy, 19 (7%) with genetic generalized epilepsy, and 16 (6%) with other or unclassified epilepsy syndromes. Only 26 (10%) patients had never received levetiracetam (LEV), whereas 133 (50.8%) were switched from LEV. The length of BRV exposure ranged from 1 day to 5 years, with a median retention time of 1.6 years, resulting in a total BRV exposure time of 6829 months (569 years). The retention rate was 61.1% at 12 months, with a reported efficacy of 33.1% (79/239; 50% responder rate, 23 patients lost-to-follow-up), including 10.9% reported as seizure-free. The retention rate for the entire study period was 50.8%, and at last follow-up, 133 patients were receiving BRV at a mean dose of 222 ± 104 mg (median = 200, range = 25-400), including 52 (39.1%) who exceeded the recommended upper dose of 200 mg. Fewer concomitant antiseizure medications and switching from LEV to BRV correlated with better short-term responses, but no investigated parameters correlated with positive long-term outcomes. BRV was discontinued in 63 (24%) patients due to insufficient efficacy, in 29 (11%) for psychobehavioral adverse events, in 25 (10%) for other adverse events, and in 24 (9%) for other reasons. SIGNIFICANCE: BRV showed a clinically useful 50% responder rate of 33% at 12 months and overall retention of >50%, despite 90% of included patients having previous LEV exposure. BRV was well tolerated; however, psychobehavioral adverse events occurred in one out of 10 patients. Although we identified short-term response and retention predictors, we could not identify significant predictors for long-term outcomes.

Patients with a relapsing course of steroid-responsive encephalopathy associated with autoimmune thyroiditis exhibit persistent intrathecal CD4+ T-cell activation.

BACKGROUND AND PURPOSE: Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT) is a rare condition defined by encephalopathy with acute or subacute onset, the presence of serum anti-thyroid antibodies, and reasonable exclusion of alternative causes. Despite having strong response towards corticosteroid treatment, some patients exhibit a chronic-relapsing course and require long-term immunosuppression. Markers for early identification of those patients are still absent. Thus, we aimed to characterise clinical as well as laboratory parameters of our local SREAT cohort. METHODS: We retrospectively evaluated a cohort of 22 SREAT patients treated in our hospital from January 2014. RESULTS: A total of 14 patients with a monophasic disease course and eight patients with multiple relapses were identified. Neither baseline characteristics nor routine cerebrospinal fluid (CSF) parameters were able to distinguish between those patient groups. Flow cytometry following initial relapse therapy showed treatment-resistant sequestration of activated CD4+ T cells in patients with a relapsing disease course, whereas other lymphocyte subsets showed uniform changes. Such changes were also present in long-term follow-up CSF examination. CONCLUSION: Our findings indicate a potential biomarker for risk stratification in patients with SREAT. Currently, it remains unclear whether the observed two phenotypes are different spectra of SREAT or represent separate diseases in terms of pathophysiology.

Blood and cerebrospinal fluid immune cell profiles in patients with temporal lobe epilepsy of different etiologies.

Inflammation plays a role in the pathogenesis of immune-mediated epilepsy, but also in epilepsy of other etiology such as hippocampal sclerosis. This study aimed to characterize immune cell signatures in the peripheral blood (PB) and cerebrospinal fluid (CSF) in temporal lobe epilepsy (TLE) of different etiologies. We retrospectively evaluated CSF routine parameters and immune cell profiles using flow cytometry in a cohort of 51 patients and 45 age-matched controls with functional disorders. Groups were comprised of patients with nonlesional TLE (n = 26), TLE due to hippocampal sclerosis (n = 14), or limbic encephalitis with antibodies against the 65-kDa isoform of glutamic acid decarboxylase (GAD65-LE; n = 11). TLE patients showed increased proportions of human leukocyte antigen-DR isotype (HLA-DR)-expressing CD4+ T lymphocytes in the CSF. Furthermore, they were characterized by a shift in monocyte subsets toward immature CD14low CD16+ cells in the PB and blood/CSF-barrier dysfunction. Whereas TLE patients in general showed similar immune cell profiles, patients with GAD65-LE differed from other TLE patients by increased proportions of HLA-DR-expressing CD8+ T lymphocytes and type 2/3 oligoclonal bands. These findings point to a role of innate and adaptive immunity in TLE. CSF parameters may help to discriminate epilepsy patients from controls and different forms of TLE from each other.

Cell injury and receptor expression in the epileptic human amygdala.

Neuropathological findings in the amygdala obtained from patients with mesial temporal lobe epilepsy (MTLE) indicate varying degrees of histopathological alterations, such as neuronal loss and gliosis. The mechanisms underlying cellular damage in the amygdala of patients with MTLE have not been fully elucidated. In the present study, we assess cellular damage, determine the receptor expression of major inhibitory and excitatory neurotransmitters, and evaluate the correlation between the expression of various receptors and cell damage in the basolateral complex and the centromedial areas in the amygdala specimens resected during brain surgery on 30 patients with medically intractable MTLE. Our data reveal an increased rate of cell damage and apoptosis as well as decreased expression levels of several GABAergic receptor subunits (GABAARα1, GABAARß3, and GABABR1) and GAD65 in the amygdalae obtained during epilepsy surgery compared to autopsy specimens. Analyses of the expression of glutamate excitatory receptor subunits (NR1, NR2B, mGluR1α, GluR1, and GluR2) reveal no significant differences between the epileptic amygdalae and autopsy control tissues. Furthermore, the increased occurrence of apoptotic cells in the amygdala is negatively correlated with the reduced expression of the studied GABAergic receptor subunits and GAD65 but is not correlated with the expression of excitatory receptors. The present data point to the importance of GABAergic neurotransmission in seizure-induced cell injury in the amygdala of patients with MTLE and suggest several GABA receptor subunits as potential druggable target structures to control epilepsy and its comorbid disorders, such as anxiety.

KEAP1 inhibition is neuroprotective and suppresses the development of epilepsy.

Hippocampal sclerosis is a common acquired disease that is a major cause of drug-resistant epilepsy. A mechanism that has been proposed to lead from brain insult to hippocampal sclerosis is the excessive generation of reactive oxygen species, and consequent mitochondrial failure. Here we use a novel strategy to increase endogenous antioxidant defences using RTA 408, which we show activates nuclear factor erythroid 2-related factor 2 (Nrf2, encoded by NFE2L2) through inhibition of kelch like ECH associated protein 1 (KEAP1) through its primary sensor C151. Activation of Nrf2 with RTA 408 inhibited reactive oxygen species production, mitochondrial depolarization and cell death in an in vitro model of seizure-like activity. RTA 408 given after status epilepticus in vivo increased ATP, prevented neuronal death, and dramatically reduced (by 94%) the frequency of late spontaneous seizures for at least 4 months following status epilepticus. Thus, acute KEAP1 inhibition following status epilepticus exerts a neuroprotective and disease-modifying effect, supporting the hypothesis that reactive oxygen species generation is a key event in the development of epilepsy.