PD-1 Is an Immune-Inflammatory Potential Biomarker in Cerebrospinal Fluid and Serum of Intractable Epilepsy

Regulatory T cells as a possible new target in epilepsy?

Epilepsy is a complex chronic brain disorder with diverse clinical features that can be caused by various triggering events, such as infections, head trauma, or stroke. During epileptogenesis, various abnormalities are observed, such as altered cellular homeostasis, imbalance of neurotransmitters, tissue changes, and the release of inflammatory mediators, which in combination lead to spontaneous recurrent seizures. Regulatory T cells (Tregs), a subtype of CD4+Foxp3+ T cells, best known for their key function in immune suppression, also seem to play a role in attenuating neurodegeneration and suppressing pathological inflammation in several brain disease states. Considering that epilepsy is also highly associated with neuronal damage and neuroinflammation, modulation of Tregs may be an interesting way to modify the disease course of epilepsy and needs further investigation. In this review, we will describe the currently available information on Tregs in epilepsy.

Blister formation in acute compartment syndrome: Unraveling the underlying predictors

Blisters are a common complication of orthopedic trauma and can cause surgery delay and increase the risk of infection. This study aims to identify risk factors for blisters in patients with acute compartment syndrome (ACS). Our study collected data from 206 ACS patients admitted to 2 hospitals between November 2013 and January 2021. Patients were divided into 2 groups: the blister group (BG) and the control group (CG), based on the presence or absence of blisters. We conducted univariate analysis, logistic regression analysis, and receiver operating characteristic (ROC) curve analysis to identify any significant differences in demographics, comorbidities, and admission laboratory test results between the 2 groups. Our study found that the incidence of blisters in ACS patients was 21.8% (45 out of 206). Univariate analysis identified several factors that were significantly associated with blister formation. Logistic regression analysis showed that patients who developed ACS in the winter or spring (P = .007, OR = 2.690, 95% CI [1.308-5.534]), patients who received a referral (the process whereby patients are transferred between medical facilities for further evaluation and treatment attempts prior to admission to our hospital) (P = .009, OR = 4.235, 95% CI [1.432-12.527]), and patients with higher PLR (P = .036, OR = 1.005, 95% CI [1.000-1.009]) were independent risk factors for blisters. Additionally, a history of drinking (P = .039, OR = 0.027, 95% CI [0.046-0.927]) was found to be a protective factor for blister formation in these patients. Moreover, ROC curve analysis showed that a PLR value of 138 was the cutoff point for predicting the development of blisters in ACS patients. Our study identified seasonal factors (refer to these months like winter or spring), referral, and patients with higher PLR as independent risk factors, and a history of drinking as a protective factor for blister formation in ACS patients. These findings allow clinicians to individualize the evaluation of blister risk and perform early targeted therapies.

Anti-PD-1 treatment protects against seizure by suppressing sodium channel function

AIMS

Although programmed cell death protein 1 (PD-1) typically serves as a target for immunotherapies, a few recent studies have found that PD-1 is expressed in the nervous system and that neuronal PD-1 might play a crucial role in regulating neuronal excitability. However, whether brain-localized PD-1 is involved in seizures and epileptogenesis is still unknown and worthy of in-depth exploration.

METHODS

The existence of PD-1 in human neurons was confirmed by immunohistochemistry, and PD-1 expression levels were measured by real-time quantitative PCR (RT-qPCR) and western blotting. Chemoconvulsants, pentylenetetrazol (PTZ) and cyclothiazide (CTZ), were applied for the establishment of in vivo (rodents) and in vitro (primary hippocampal neurons) models of seizure, respectively. SHR-1210 (a PD-1 monoclonal antibody) and sodium stibogluconate (SSG, a validated inhibitor of SH2-containing protein tyrosine phosphatase-1 [SHP-1]) were administrated to investigate the impact of PD-1 pathway blockade on epileptic behaviors of rodents and epileptiform discharges of neurons. A miRNA strategy was applied to determine the impact of PD-1 knockdown on neuronal excitability. The electrical activities and sodium channel function of neurons were determined by whole-cell patch-clamp recordings. The interaction between PD-1 and α-6 subunit of human voltage-gated sodium channel (Nav1.6) was validated by performing co-immunostaining and co-immunoprecipitation (co-IP) experiments.

RESULTS

Our results reveal that PD-1 protein and mRNA levels were upregulated in lesion cores compared with perifocal tissues of surgically resected specimens from patients with intractable epilepsy. Furthermore, we show that anti-PD-1 treatment has anti-seizure effects both in vivo and in vitro. Then, we reveal that PD-1 blockade can alter the electrophysiological properties of sodium channels. Moreover, we reveal that PD-1 acts together with downstream SHP-1 to regulate sodium channel function and hence neuronal excitability. Further investigation suggests that there is a direct interaction between neuronal PD-1 and Nav1.6.

CONCLUSION

Our study reveals that neuronal PD-1 plays an important role in epilepsy and that anti-PD-1 treatment protects against seizures by suppressing sodium channel function, identifying anti-PD-1 treatment as a novel therapeutic strategy for epilepsy.

Retracted: PD-1 Is an Immune-Inflammatory Potential Biomarker in Cerebrospinal Fluid and Serum of Intractable Epilepsy

[This retracts the article DOI: 10.1155/2021/7973123.].

Inflammation-related genes and immune infiltration landscape identified in kainite-induced temporal lobe epilepsy based on integrated bioinformatics analysis

BACKGROUND

Temporal lobe epilepsy (TLE) is a common brain disease. However, the pathogenesis of TLE and its relationship with immune infiltration remains unclear. We attempted to identify inflammation-related genes (IRGs) and the immune cell infiltration pattern involved in the pathological process of TLE via bioinformatics analysis.

MATERIALS AND METHODS

The GSE88992 dataset was downloaded from the Gene Expression Omnibus (GEO) database to perform differentially expressed genes screening and weighted gene co-expression network analysis (WGCNA). Subsequently, the functional enrichment analysis was performed to explore the biological function of the differentially expressed IRGs (DEIRGs). The hub genes were further identified by the CytoHubba algorithm and validated by an external dataset (GSE60772). Furthermore, the CIBERSORT algorithm was applied to assess the differential immune cell infiltration between control and TLE groups. Finally, we used the DGIbd database to screen the candidate drugs for TLE.

RESULTS

34 DEIRGs (33 up-regulated and 1 down-regulated gene) were identified, and they were significantly enriched in inflammation- and immune-related pathways. Subsequently, 4 hub DEIRGs (Ptgs2, Jun, Icam1, Il6) were further identified. Immune cell infiltration analysis revealed that T cells CD4 memory resting, NK cells activated, Monocytes and Dendritic cells activated were involved in the TLE development. Besides, there was a significant correlation between hub DEIRGs and some of the specific immune cells.

CONCLUSION

4 hub DEIRGs (Ptgs2, Jun, Icam1, Il6) were associated with the pathogenesis of TLE via regulation of immune cell functions, which provided a novel perspective for the understanding of TLE.

Potential clinical and biochemical markers for the prediction of drug-resistant epilepsy: A literature review

Drug resistance is a major challenge in the treatment of epilepsy. Drug-resistant epilepsy (DRE) accounts for 30% of all cases of epilepsy and is a matter of great concern because of its uncontrollability and the high burden, mortality rate, and degree of damage. At present, considerable research has focused on the development of predictors to aid in the early identification of DRE in an effort to promote prompt initiation of individualized treatment. While multiple predictors and risk factors have been identified, there are currently no standard predictors that can be used to guide the clinical management of DRE. In this review, we discuss several potential predictors of DRE and related factors that may become predictors in the future and perform evidence rating analysis to identify reliable potential predictors.

Epilepsy Characteristics in Neurodevelopmental Disorders: Research from Patient Cohorts and Animal Models Focusing on Autism Spectrum Disorder

Epilepsy, a heterogeneous group of brain-related diseases, has continued to significantly burden society and families. Epilepsy comorbid with neurodevelopmental disorders (NDDs) is believed to occur due to multifaceted pathophysiological mechanisms involving disruptions in the excitation and inhibition (E/I) balance impeding widespread functional neuronal circuitry. Although the field has received much attention from the scientific community recently, the research has not yet translated into actionable therapeutics to completely cure epilepsy, particularly those comorbid with NDDs. In this review, we sought to elucidate the basic causes underlying epilepsy as well as those contributing to the association of epilepsy with NDDs. Comprehensive emphasis is put on some key neurodevelopmental genes implicated in epilepsy, such as MeCP2, SYNGAP1, FMR1, SHANK1-3 and TSC1, along with a few others, and the main electrophysiological and behavioral deficits are highlighted. For these genes, the progress made in developing appropriate and valid rodent models to accelerate basic research is also detailed. Further, we discuss the recent development in the therapeutic management of epilepsy and provide a briefing on the challenges and caveats in identifying and testing species-specific epilepsy models.

Emerging Roles of T Helper Cells in Non-Infectious Neuroinflammation: Savior or Sinner

CD4⁺ T cells, also known as T helper (Th) cells, contribute to the adaptive immunity both in the periphery and in the central nervous system (CNS). At least seven subsets of Th cells along with their signature cytokines have been identified nowadays. Neuroinflammation denotes the brain’s immune response to inflammatory conditions. In recent years, various CNS disorders have been related to the dysregulation of adaptive immunity, especially the process concerning Th cells and their cytokines. However, as the functions of Th cells are being discovered, it’s also found that their roles in different neuroinflammatory conditions, or even the participation of a specific Th subset in one CNS disorder may differ, and sometimes contrast. Based on those recent and contradictory evidence, the conflicting roles of Th cells in multiple sclerosis, Alzheimer’s disease, Parkinson’s disease, epilepsy, traumatic brain injury as well as some typical mental disorders will be reviewed herein. Research progress, limitations and novel approaches concerning different neuroinflammatory conditions will also be mentioned and compared.

Identification of Potential Immune Checkpoint Inhibitor Targets in Gliomas via Bioinformatic Analyses

Background. Glioma is a common tumor originating from the glial cells of the brain. Immune checkpoint inhibitors can potentially be used to treat gliomas, although no drug is currently approved. Methods. The expression levels of the immune checkpoint genes in glioma and normal tissues, and their correlation with the IDH mutation status and complete 1p/19q codeletion, were analyzed using The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) databases. Survival analyses were conducted using the CGGA database. Protein-protein interaction and functional enrichment analyses were performed via the STRING database using GO, KEGG, and Reactome pathways. The correlation between the immune checkpoints and the immune cell infiltration was determined using the TISIDB and TIMER databases. Results. HAVCR2 was overexpressed in the gliomas compared to normal brain tissues, as well as in the high-grade glioma patients and significantly downregulated in IDH mutant or 1p/19q codeletion patients. Overexpression of HAVCR2 was associated with poor survival in tumor grades II, III, and IV and was the most correlated with immune infiltration of B and T cells. Conclusion. HAVCR2 can be a potential therapeutic target for cancer immunotherapy for glioma patients.