Anti-thyroid peroxidase antibody in stroke localization: exordium doorway of preliminary findings in thyroidology?

OBJECTIVE: Stroke is a chronic health problem that affects all areas of life. The presence of thyroid autoantibodies can augment the severity of stroke. The aim of this work is to investigate whether there is a relationship between the site of stroke involvement and the anti-thyroid peroxidase antibody (anti-TPO) or not. This is the first study in the English-language literature. METHODS: A total of 39 patients with a diagnosis of acute ischemic stroke were included, and the cases under 18 years of age with an infection and the ones with autoimmune diseases other than Hashimoto's thyroiditis were excluded from the study design. The patients' age, gender, smoking status, comorbid conditions, and stroke localization in brain imaging were recorded. The region involving the anterior circulation area originating from the internal carotid artery was evaluated as anterior, and the region possessing the vertebrobasilar circulation area from the vertebral arteries was considered posterior involvement. Thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), triglyceride, high-density lipoprotein (HDL), low-density lipoprotein (LDL), C-reactive protein (CRP), sedimentation, and anti-TPO were retrospectively analyzed. RESULTS: As a consequence, gender distribution, smoking, comorbid conditions, TSH, T3, T4, triglyceride, HDL, LDL, CRP, and sedimentation did not differ significantly, while the age of the posterior-located stroke was lower than that of the cases with the anterior. The anti-TPO value was significantly lower in posterior-located strokes than in the anterior system. CONCLUSION: In summary, the anti-TPO value was recognized as higher in the anterior stroke localization. Thyroiditis and accompanying anti-TPO autoantibody positivity are conditions that should not be ignored by thyroidologists and thyroid-health providers.

Brain border-derived CXCL2+ neutrophils drive NET formation and impair vascular reperfusion following ischemic stroke.

BACKGROUND: The brain border compartments harbor a diverse population of immune cells and serve as invasion sites for leukocyte influx into the brain following CNS injury. However, how brain-border myeloid cells affect stroke pathology remains poorly characterized. METHODS AND RESULTS: Here, we showed that ischemic stroke-induced expansion of CXCL2+ neutrophils, which exhibit highly proinflammatory features. We tracked CXCL2+ neutrophils in vivo by utilizing a photoconvertible Kik-GR mouse (fluorescent proteins Kikume Green Red, Kik-GR) and found that brain-infiltrating CXCL2+ neutrophils following ischemic stroke were mainly derived from the brain border rather than the periphery. We demonstrated that CXCL2 neutralization inhibited the formation and releasing of neutrophil extracellular traps (NETs) from in vitro cultured primary neutrophils. Furthermore, CXCL2-neutralizing antibody treatment reduced brain infarcts and improved vascular reperfusion at day 3 postischemic stroke. CONCLUSIONS: Collectively, brain border-derived CXCL2+ neutrophil expansion may impair vascular reperfusion by releasing NETs following ischemic stroke.

The Alteration of Circulating Invariant Natural Killer T, γδT, and Natural Killer Cells after Ischemic Stroke in Relation to Clinical Outcomes: A Prospective Case-Control Study.

The adaptive response occurs only after 7-10 days of antigen presentation. Nevertheless, the autoreactive T cells infiltrate the stroke lesion within the first 48 h. Thus, we hypothesized that the unconventional lymphocytes as invariant natural killer T cells (iNKT) and γδT cells that share immediate innate and delayed adaptive response features are involved in acute stroke pathophysiology. We assessed prospectively the quantity of circulating iNKT cells, γδT cells, and NK cells with flow cytometry in 52 subjects within three months after stroke, and we compared the results with those obtained in age-, sex-, and vascular risk factor-matched controls. We studied lymphocyte parameters regarding clinical outcomes, infarct volume, stroke-associated infection (SAI), and burden risk factors. The reduced number of circulating γδT cells and decreased percentage of the Vδ2 subset in the acute phase of stroke correlated with worse neurological status in the recovery phase. In subjects treated with thrombolysis and those who developed SAI, a lower percentage of γδT cells in the 90-day follow-up was observed. An increased percentage of iNKT cells in the acute and subacute phases of stroke was observed, and it was related to the worse clinical status. The circulating NK cells do not change temporarily or affect the outcomes after stroke. It seems that γδT cells play a long-lasting role in ischemic stroke, mainly related to the Vδ2 subset. The role of iNKT cells appears to be detrimental, especially in the acute and subacute phases of stroke. The effect of circulating NK cells on the outcome after stroke seems negligible.

Construction of a diagnostic model for ischemic stroke based on immune-related genes.

INTRODUCTION: This study aimed to screen immune-related marker genes of ischemic stroke (IS). MATERIAL AND METHODS: Two IS-related gene expression datasets were downloaded. The significantly differentially expressed genes (DEGs) and miRNAs (DEMs) between IS and control groups were selected. The differential immune cells were analysed. Weighted gene co-expression network analysis (WGCNA) was applied to analyse immune-related genes, followed by function analysis and interaction network construction. Then, key genes were further screened using optimization algorithm to construct a diagnostic model. Finally, miRNA regulatory network of several key genes was established. RESULTS: In total 321 DEGs and 140 DEMs were obtained. 11 immune cell types were significantly different between IS and control groups. WGCNA identified two key modules, involving 202 differential immune genes. The greenyellow module was enriched in biological processes and pathways associated with T cells, while the midnightblue module was mainly associated with apoptosis, and inflammatory response-related functions and pathways. Protein interaction network identified 10 hub nodes, such as CD8A, ITGAM and TLR4. LASSO regression selected 8 key feature genes, and a risk score model was established. Key model genes were enriched in 63 GO biological processes, such as microglial cell activation, and B cell apoptotic process, and 3 KEGG pathways, such as negative regulation of nuclear cell cycle DNA replication, and hematopoietic cell lineage. Finally, a total of 25 miRNA-target relationship pairs were obtained. CONCLUSIONS: This study identified some immune-related marker genes and constructed a diagnostic model based on 8 immune-related genes in IS.

Benserazide is neuroprotective and improves functional recovery after experimental ischemic stroke by altering the immune response.

Stroke is a leading cause of permanent disability worldwide. Despite intensive research over the last decades, key anti-inflammatory strategies that have proven beneficial in pre-clinical animal models have often failed in translation. The importance of neutrophils as pro- and anti-inflammatory peripheral immune cells has often been overlooked in ischemic stroke. However, neutrophils rapidly infiltrate into the brain parenchyma after stroke and secrete an array of pro-inflammatory factors including reactive oxygen species, proteases, cytokines, and chemokines exacerbating damage. In this study, we demonstrate the neuroprotective and anti-inflammatory effect of benserazide, a clinically used DOPA decarboxylase inhibitor, using both in vitro models of inflammation and in vivo mouse models of focal cerebral ischemia. Benserazide significantly attenuated PMA-induced NETosis in isolated human neutrophils. Furthermore, benserazide was able to protect both SH-SY5Y and iPSC-derived human cortical neurons when challenged with activated neutrophils demonstrating the clinical relevance of this study. Additional in vitro data suggest the ability of benserazide to polarize macrophages towards M2-phenotypes following LPS stimulation. Neuroprotective effects of benserazide are further demonstrated by in vivo studies where peripheral administration of benserazide significantly attenuated neutrophil infiltration into the brain, altered microglia/macrophage phenotypes, and improved the behavioral outcome post-stroke. Overall, our data suggest that benserazide could serve as a drug candidate for the treatment of ischemic stroke. The importance of our results for future clinical trials is further underlined as benserazide has been approved by the European Medicines Agency as a safe and effective treatment in Parkinson's disease when combined with levodopa.

Microglia LILRB4 upregulation reduces brain damage after acute ischemic stroke by limiting CD8+ T cell recruitment.

BACKGROUND: Leukocyte immunoglobulin-like receptor B4 (LILRB4) plays a significant role in regulating immune responses. LILRB4 in microglia might influence the infiltration of peripheral T cells. However, whether and how LILRB4 expression aggravates brain damage after acute ischemic stroke remains unclear. This study investigates the role of LILRB4 in modulating the immune response and its potential protective effects against ischemic brain injury in mice. METHODS AND RESULTS: Microglia-specific LILRB4 conditional knockout (LILRB4-KO) and overexpression transgenic (LILRB4-TG) mice were constructed by a Cre-loxP system. Then, they were used to investigate the role of LILRB4 after ischemic stroke using a transient middle cerebral artery occlusion (tMCAO) mouse model. Spatial transcriptomics analysis revealed increased LILRB4 expression in the ischemic hemisphere. Single-cell RNA sequencing (scRNA-seq) identified microglia-cluster3, an ischemia-associated microglia subcluster with elevated LILRB4 expression in the ischemic brain. Flow cytometry and immunofluorescence staining showed increased CD8+ T cell infiltration into the brain in LILRB4-KO-tMCAO mice. Behavioral tests, cortical perfusion maps, and infarct size measurements indicated that LILRB4-KO-tMCAO mice had more severe functional deficits and larger infarct sizes compared to Control-tMCAO and LILRB4-TG-tMCAO mice. T cell migration assays demonstrated that LILRB4-KD microglia promoted CD8+ T cell recruitment and activation in vitro, which was mitigated by CCL2 inhibition and recombinant arginase-1 addition. The scRNA-seq and spatial transcriptomics identified CCL2 was predominantly secreted from activated microglia/macrophage and increased CCL2 expression in LILRB4-KD microglia, suggesting a chemokine-mediated mechanism of LILRB4. CONCLUSION: LILRB4 in microglia plays a crucial role in modulating the post-stroke immune response by regulating CD8+ T cell infiltration and activation. Knockout of LILRB4 exacerbates ischemic brain injury by promoting CD8+ T cell recruitment. Overexpression of LILRB4, conversely, offers neuroprotection. These findings highlight the therapeutic potential of targeting LILRB4 and its downstream pathways to mitigate immune-mediated damage in ischemic stroke.

Impact of peripheral lymphocyte subsets on prognosis for patients after acute ischemic stroke: A potential disease prediction model approach.

AIMS: To investigate the relationship between peripheral blood lymphocyte subsets and prognosis in patients with acute ischemic stroke (AIS). METHODS: We enrolled 294 patients with AIS and collected peripheral blood samples for analysis of lymphocyte subsets. Prognosis was assessed at 3 months using the modified Rankin Scale (mRS). Association between lymphocyte count and poor outcomes (mRS score >2) was assessed using logistic regression. Individualized prediction models were developed to predict poor outcomes. RESULTS: Patients in the mRS score ≤2 group had higher T-cell percentage (odds ratio [OR] = 0.947; 95% confidence interval [CI]: 0.899-0.998; p = 0.040), CD3+ T-cell count (OR = 0.999; 95% CI: 0.998-1.000; p = 0.018), and CD4+ T-cell count (OR = 0.998; 95% CI: 0.997-1.000; p = 0.030) than those in the mRS score >2 group 1-3 days after stroke. The prediction model for poor prognosis based on the CD4+ T-cell count showed good discrimination (area under the curve of 0.844), calibration (p > 0.05), and clinical utility. CONCLUSION: Lower T cell percentage, CD3+, and CD4+ T-cell counts 1-3 days after stroke were independently associated with increased risk of poor prognosis. Individualized predictive model of poor prognosis based on CD4+ T-cell count have good accuracy and may predict disease prognosis.

The Influence of SARS-CoV-2 Infection on the Development of Selected Neurological Diseases.

In 2024, over 775 million cases of COVID-19 were recorded, including approximately 7 million deaths, indicating its widespread and dangerous nature. The disease is caused by the SARS-CoV-2 virus, which can manifest a wide spectrum of symptoms, from mild infection to respiratory failure and even death. Neurological symptoms, such as headaches, confusion, and impaired consciousness, have also been reported in some COVID-19 patients. These observations suggest the potential of SARS-CoV-2 to invade the central nervous system and induce neuroinflammation during infection. This review specifically explores the relationship between SARS-CoV-2 infection and selected neurological diseases such as multiple sclerosis (MS), ischemic stroke (IS), and Alzheimer's disease (AD). It has been observed that the SARS-CoV-2 virus increases the production of cytokines whose action can cause the destruction of the myelin sheaths of nerve cells. Subsequently, the body may synthesize autoantibodies that attack nerve cells, resulting in damage to the brain's anatomical elements, potentially contributing to the onset of multiple sclerosis. Additionally, SARS-CoV-2 exacerbates inflammation, worsening the clinical condition in individuals already suffering from MS. Moreover, the secretion of pro-inflammatory cytokines may lead to an escalation in blood clot formation, which can result in thrombosis, obstructing blood flow to the brain and precipitating an ischemic stroke. AD is characterized by intense inflammation and heightened oxidative stress, both of which are exacerbated during SARS-CoV-2 infection. It has been observed that the SARS-CoV-2 demonstrates enhanced cell entry in the presence of both the ACE2 receptor, which is already elevated in AD and the ApoE ε4 allele. Consequently, the condition worsens and progresses more rapidly, increasing the mortality rate among AD patients. The above information underscores the numerous connections between SARS-CoV-2 infection and neurological diseases.

Comprehensive immune modulation mechanisms of Angong Niuhuang Wan in ischemic stroke: Insights from mass cytometry analysis.

BACKGROUND: Angong Niuhuang Wan (AGNHW, ), is a classical medicinal formula in Traditional Chinese Medicine (TCM) that has been appreciated for its neuroprotective properties in ischemic cerebral injuries, yet its intricate mechanisms remain only partially elucidated. AIMS: This study leverages advanced Mass cytometry (CyTOF) to analyze AGNHW's multifaceted immunomodulation effects in-depth, emphasizing previously underexplored areas. RESULTS: AGNHW mitigated monocyte-derived macrophages (MoDM) infiltration in the brain, distinguishing its effects on those from microglia. While the vehicle group exhibited elevated inflammatory markers like CD4, CD8a, and CD44 in ischemic brains, the AGNHW-treated group attenuated their expressions, indicating AGNHW's potential to temper the post-ischemic inflammatory response. Systemically, AGNHW modulated fundamental immune cell dynamics, notably augmenting CD8+ T cells, B cells, monocytes, and neutrophil counts in the peripheral blood under post-stroke conditions. Intracellularly, AGNHW exhibited its targeted modulation of the signaling pathways, revealing a remarked inhibition of key markers like IκBα, indicating potential suppression of inflammatory responses in ischemic brain injuries. CONCLUSION: This study offers a comprehensive portrait of AGNHW's immunomodulation effects on ischemic stroke, illuminating its dual sites of action-both cerebral and systemic-and its nuanced modulation of cellular and molecular dynamics.

Peripheral immunity is associated with cognitive impairment after acute minor ischemic stroke and transient ischemic attack.

Immunoinflammation is associated with the development of post-stroke cognitive impairment (PSCI), however, peripheral immunity has not been fully explored. We aimed to investigate the association between PSCI and peripheral immune indicators, including neutrophil, lymphocyte, and mononuclear percentages and counts; the systemic immune inflammation index; platelet-to-lymphocyte ratio; neutrophil-to-lymphocyte ratio (NLR); and lymphocyte-to-monocyte ratio. A total of 224 patients with acute minor ischemic stroke or transient ischemic attack with 6-12 months of follow-up were included. PSCI was defined as a Montreal Cognitive Assessment score < 22 during the follow-up period. We performed logistic regression, subgroup analyses based on age and sex, and further established predictive models. We found that increased innate immunity indicators (neutrophils, neutrophil percentage) increased the risk of PSCI, whereas increased adaptive immunity indicator (lymphocytes) were protective against PSCI, especially in patients aged 50-65 years. Neutrophil percentage and NLR improved the predictive efficacy of the models that included demographic, clinical, and imaging information, with the area under the curve increased from 0.765 to 0.804 and 0.803 (P = 0.042 and 0.049, respectively). We conducted a comprehensive analysis of peripheral immunity in PSCI, providing a novel perspective on the early detection, etiology, and treatment of PSCI.

Vagus nerve stimulation (VNS) inhibits cardiac mast cells activation and improves myocardial atrophy after ischemic stroke.

BACKGROUND: Ischemic stroke is one of the leading causes of chronic disability worldwide, and stroke-induced heart damage can lead to death. According to research, patients with a variety of brain disease have good clinical results after vagus nerve stimulation (VNS). After ischemic stroke, mast cells (MCs) degranulate and release a large number of mediators, which may cause systemic inflammation. Chymase secreted by MCs can increase the levels of pathological angiotensin II (AngⅡ), which plays a crucial role in the deterioration of heart disease. Our goal was to develop a minimally invasive, targeted, and convenient VNS approach to assess the impact of VNS and to clarify the relationship between VNS and MCs in the prognosis of patients with myocardial atrophy after acute ischemic stroke. METHODS: In this study, we verified the role of VNS in the treatment of myocardial atrophy after stroke and its molecular mechanism using a rat model of middle cerebral artery occlusion (MCAO/r). Behavioral studies were assessed using neurobehavioral deficit scores. Enzyme-linked immunosorbent assays, immunofluorescence staining, Western blotting and qRT-PCR were used to analyze the expression levels of myocardial atrophy, MC and inflammatory markers in rat hearts. RESULTS: VNS improved myocardial atrophy in MCAO/r rats, inhibited MC activation, reduced the expression of chymase and AngⅡ, and inhibited the expression of proinflammatory factors. The chymase activator C48/80 reversed these effects of VNS. Chymase activation inhibited the effect of VNS on myocardial atrophy in MCAO/r rats, increased AngⅡ expression and aggravated inflammation and autophagy. The myocardial atrophy of MCAO/r rats was improved after chymase inhibition, and AngⅡ expression, inflammation and autophagy were reduced. Our results suggest that VNS may reduce the expression of chymase and AngⅡ by inhibiting MC activation, thereby improving myocardial atrophy and reducing inflammation and autophagy in MCAO/r rats. Inhibition of MC activation may be an effective strategy for treating myocardial atrophy after stroke. CONCLUSIONS: VNS inhibits MC activation and reduces the expression of chymase and AngII, thereby alleviating myocardial atrophy, inflammation and autophagy after stroke.

Antiphospholipid antibodies as potential prognostic indicators of recurrent ischemic stroke.

BACKGROUND: Immunity play a pivotal role in the risk of ischemic stroke, and studies have also shown a relationship between ischemic stroke and autoimmune diseases. In light of this we conducted a prospective cohort study to elucidate the impact of antiphospholipid antibodies (aPLs), antinuclear antibodies (ANA), and anti-extractable nuclear antigen autoantibodies (anti-ENA) on the prognosis of ischemic stroke. METHODS: 245 stroke patients were recruited in this single-center study and followed up with for 3 years. Autoantibodies, including aPLs (ACA, anti-ß2GPI, LA), ANA and anti-ENA were evaluated in recurrent ischemic stroke (RIS) and nonrecurrent ischemic stroke (nonRIS). Stroke severity was judged using the National Institutes of Health Stroke Scale (NIHSS). For preventive treatment, 42 IS patients with positive aPLs + ANA/anti-ENA were randomized 1:1 into a hydroxychloroquine (HCQ) treatment group and a control group, and the prognoses were compared. RESULTS: The positive rate of ACA IgG (p = 0.018), anti-ß2GPI IgG (p = 0.047), LA (p = 0.023), and aPLs + ANA/anti-ENA (p = 0.000) were significantly higher in patients with RIS compared to patients with nonRIS, and aPLs + ANA/anti-ENA (HR2.31, 95 % CI1.02-5.25, p = 0.046) and hypertension (HR2.50, 95 % CI1.17-5.35, p = 0.018) were the independent risk factors of recurrence. There were differences in NIHSS at month 36 between those positive and negative for aPLs + ANA/anti-ENA (p = 0.001, Eta2 = 0.052), anti-ENA (p = 0.016, Eta2 = 0.030), ANA (p = 0.035, Eta2 = 0.022), and LA (p = 0.016, Eta2 = 0.028). Furthermore, the recurrence rate of the HCQ treatment group was lower than that of the control group (p = 0.024). CONCLUSIONS: Co-positivity of aPLs and ANA/anti-ENA is an independent risk factor for RIS. However, HCQ therapy may reduce the recurrence rate of IS for these patients.

Evaluation of the causal effects of immune cells on ischemic stroke: a Mendelian randomization study.

Background: Ischemic stroke (IS) is a cerebrovascular disease caused by various factors, and its etiology remains inadequately understood. The role of immune system dysfunction in IS has been increasingly recognized. Our objective was to evaluate whether circulating immune cells causally impact IS risk. Methods: We conducted two-sample Mendelian randomization analyses to evaluate the causal effects of 731 immune cell traits on IS, utilizing publicly available genome-wide association studies (GWAS) summary statistics for 731 immune cell traits as exposure data, and two GWAS statistics for IS as outcome data. A set of sensitivity analyses, including Cochran's Q test, I 2 statistics, MR-Egger intercept test, MR-PRESSO global test, and leave-one-out sensitivity analyses, were performed to assess the robustness of the results. Additionally, meta-analyses were conducted to combine the results from the two different IS datasets. Finally, we extracted instrumental variables of immune cell traits with causal effects on IS in both IS datasets for SNP annotation. Results: A total of 41 and 35 immune cell traits were identified to have significant causal effects on IS based on two different IS datasets, respectively. Among them, the immune cell trait CD62L- plasmacytoid Dendritic Cell AC and CD4+ CD8dim T cell%leukocyte respectively served as risk factor and protective element in both IS datasets. The robustness of the causal effects was confirmed through the sensitivity analyses. The results of the meta-analyses further support the causal effects of CD62L- plasmacytoid Dendritic Cell AC (pooled OR=1.030, 95%CI: 1.011-1.049, P=0.002) and CD4+ CD8dim T cell%leukocyte (pooled OR=0.959, 95%CI: 0.935-0.984, P=0.001). Based on these two immune cell traits, 33 genes that may be related to the causal effects were mapped. Conclusions: Our study demonstrated the potential causal effects of circulating immune cells on IS, providing valuable insights for future studies aimed at preventing IS.

Elevated serum levels of anti-collagen type I antibodies in patients with spontaneous cervical artery dissection and ischemic stroke: a prospective multicenter study.

Introduction: Spontaneous cervical artery dissection (sCAD) is a rare vasculopathy whose trigger is still unknown. We hypothesized that autoimmunity against components of the vascular wall might play a critical role in sCAD and examined anti-collagen type I antibodies in patients with sCAD, acute ischemic stroke, patients with thromboendarterectomy, and controls. Methods: Fifty-seven patients with sCAD (age 45.7 ± 10.2 years, female 18 (31.6%)) were prospectively enrolled in four German stroke centers. Blood samples were collected at baseline, at day 10 ± 3, and after 6 ± 1 months. Patients with ischemic stroke not related to CAD (n=54, age 56.7 ± 13.7 years, female 15 (27.8%)), healthy probands (n=80, age 57.4 ± 12.9 years, female 56 (70%)), and patients undergoing thromboendarterectomy of the carotid artery (n=9, age 70.7 ± 9.3 years, female 2 (22.2%)) served as controls. Anti-collagen type I antibodies were determined by enzyme-linked immunosorbent assays (ELISAs). Results: Patients with acute sCAD had higher serum levels of anti-collagen type I antibodies (33.9 ± 24.6 µg/ml) than probands (18.5 ± 11.0 µg/ml; p <0.001) but lower levels than patients with ischemic stroke not related to sCAD (47.8 ± 28.4 µg/ml; p=0.003). In patients with sCAD, serum levels of anti-collagen type I antibodies were similar in the acute, subacute, and chronic phase. Levels of anti-collagen type I antibodies significantly correlated with circulating collagen type I (rho=0.207, p=0.003). Conclusion: Anti-collagen type I antibodies seem not to represent a trigger for acute sCAD or ischemic stroke but may rather be linked to the metabolism and turnover of collagen type I.

Flow cytometry-based peripheral blood analysis as an easily friendly tool for prognostic monitoring of acute ischemic stroke: a multicenter study.

Background and objective: Acute ischemic stroke (AIS) is a leading cause of mortality, severe neurological and long-term disability world-wide. Blood-based indicators may provide valuable information on identified prognostic factors. However, currently, there is still a lack of peripheral blood indicators for the prognosis of AIS. We aimed to identify the most promising prognostic indicators and establish prognostic models for AIS. Methods: 484 subjects enrolled from four centers were analyzed immunophenotypic indicators of peripheral blood by flow cytometry. Least absolute shrinkage and selection operator (LASSO) regression was applied to minimize the potential collinearity and over-fitting of variables measured from the same subject and over-fitting of variables. Univariate and multivariable Cox survival analysis of differences between and within cohorts was performed by log-rank test. The areas under the receiving operating characteristic (ROC) curves were used to evaluate the selection accuracy of immunophenotypic indicators in identifying AIS subjects with survival risk. The prognostic model was constructed using a multivariate Cox model, consisting of 402 subjects as a training cohort and 82 subjects as a testing cohort. Results: In the prospective study, 7 immunophenotypic indicators of distinct significance were screened out of 72 peripheral blood immunophenotypic indicators by LASSO. In multivariate cox regression, CTL (%) [HR: 1.18, 95% CI: 1.03-1.33], monocytes/µl [HR: 1.13, 95% CI: 1.05-1.21], non-classical monocytes/µl [HR: 1.09, 95% CI: 1.02-1.16] and CD56high NK cells/µl [HR: 1.13, 95% CI: 1.05-1.21] were detected to decrease the survival probability of AIS, while Tregs/µl [HR:0.97, 95% CI: 0.95-0.99, p=0.004], BM/µl [HR:0.90, 95% CI: 0.85-0.95, p=0.023] and CD16+NK cells/µl [HR:0.93, 95% CI: 0.88-0.98, p=0.034] may have the protective effect. As for indicators' discriminative ability, the AUC for CD56highNK cells/µl attained the highest of 0.912. In stratification analysis, the survival probability for AIS subjects with a higher level of Tregs/µl, BM/µl, CD16+NK cells/µl, or lower levels of CD56highNK cells/µl, CTL (%), non-classical monocytes/µl, Monocytes/µl were more likely to survive after AIS. The multivariate Cox model showed an area under the curve (AUC) of 0.805, 0.781 and 0.819 and 0.961, 0.924 and 0.982 in the training and testing cohort, respectively. Conclusion: Our study identified 7 immunophenotypic indicators in peripheral blood may have great clinical significance in monitoring the prognosis of AIS and provide a convenient and valuable predictive model for AIS.

Potential diagnostic biomarkers for immunogenic cell death in elderly female patients with ischemic stroke: identification and analysis.

Ischemic stroke (IS) is of increasing concern given the aging population and prevalence of unhealthy lifestyles, with older females exhibiting higher susceptibility. This study aimed to identify practical diagnostic markers, develop a diagnostic model for immunogenic cell death (ICD)-associated IS, and investigate alterations in the immune environment caused by hub genes. Differentially expressed genes associated with ICD in IS were identified based on weighted gene co-expression network analysis and the identification of significant modules. Subsequently, machine learning algorithms were employed to screened hub genes, which were further assessed using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Gene Set Enrichment Analysis. A nomogram mode lwas then constructed for IS diagnosis, and its diagnostic value was assessed using a receiver operating characteristic curve. Finally, alterations in immune cell infiltration were assessed within patients with IS, and the pan-cancer expression patterns of hub genes were evaluated. Three hub genes associated with ICD (PDK4, CCL20, and FBL) were identified. The corresponding nomogram model for IS diagnosis could effectively identify older female patients with IS (area under the curve (AUC) = 0.9555). Overall, the three hub genes exhibit good diagnostic value (AUC > 0.8). CCL20 and FBL are significantly associated with the extent of immune cells infiltration. Moreover, a strong link exists between hub gene expression and pan-cancer prognosis. Cumulatively, these results indicate that ICD-related hub genes critically influence IS progression in older females, presenting novel diagnostic and therapeutic targets for personalized treatment.

Dimethyl Fumarate Modulates the Immune Environment and Improves Prognosis in the Acute Phase after Ischemic Stroke.

INTRODUCTION: Dimethyl fumarate (DMF) has shown potential for protection in various animal models of neurological diseases. However, the impact of DMF on changes in peripheral immune organs and the central nervous system (CNS) immune cell composition after ischemic stroke remains unclear. METHODS: Eight-week-old C57BL/6J mice with photothrombosis ischemia and patients with acute ischemic stroke (AIS) were treated with DMF. TTC staining, flow cytometry, and immunofluorescence staining were used to evaluate the infarct volume and changes in immune cells in the periphery and the CNS. RESULTS: DMF reduced the infarct volume on day 1 after PT. DMF reduced the percentages of peripheral immune cells, such as neutrophils, dendritic cells, macrophages, and monocytes, on day 1, followed by NK cells on day 3 and B cells on day 7 after PT. In the CNS, DMF significantly reduced the percentage of monocytes in the brain on day 3 after PT. In addition, DMF increased the number of microglia in the peri-infarct area and reduced the number of neurons in the peri-infarct area in the acute and subacute phases after PT. In AIS patients, B cells decreased in patients receiving alteplase in combination with DMF. CONCLUSION: DMF can change the immune environment of the periphery and the CNS, reduce infarct volume in the acute phase, promote the recruitment of microglia and preserve neurons in the peri-infarct area after ischemic stroke.

Seipin is involved in oxygen-glucose deprivation/reoxygenation induced neuroinflammation by regulating the TLR3/TRAF3/NF-κB pathway.

Seipin plays a crucial role in lipid metabolism and is involved in neurological disorders. However, the function and mechanism of action of seipin in acute ischemic stroke have not yet been elucidated. Here, we aimed to investigate the effect of seipin on neuroinflammation induced by oxygen-glucose deprivation/reoxygenation (OGD/R) and further explore the molecular mechanism by functional experiments. Our results revealed a significant decrease in seipin mRNA levels, accompanied by enhanced expression of TNF-α in patients with AIS, and a significant negative correlation between seipin and TNF-α was observed. Additionally, there was a negative correlation between seipin levels and the National Institutes of Health Stroke Scale (NIHSS) score. Furthermore, seipin levels were also decreased in middle cerebral artery occlusion/reperfusion (MCAO/R) mice and OGD/R-treated BV2 cells. RNA sequencing analysis showed that seipin knockdown altered the Toll-like receptor 3 (TLR3) signaling pathway. It was further confirmed in vitro that seipin knockdown caused significantly increased secretion of inflammatory factors including TNF-α, interleukin (IL)-1ß, and interferon (IFN)-ß. Meanwhile, seipin knockdown activated the Tlr3 signal pathway while this effect could be reversed by Tlr3 inhibitor in OGD/R treated BV2 cells. Furthermore, neuroinflammation induced by OGD/R was significantly reduced by seipin overexpression. Overall, our study demonstrate that seipin deficiency aggravates neuroinflammation by activating the TLR3/TRAF3/NF-κB signaling pathway after OGD/R stimuli, and suggest that seipin may be a potential therapeutic target for AIS.

Peripheral inflammation and trajectories of depressive symptomology after ischemic stroke: A prospective cohort study.

BACKGROUND: Understanding the association of peripheral inflammation and post-stroke depressive symptomology (PSDS) might provide further insights into the complex etiological mechanism of organic depression. However, studies focusing on the longitudinal patterns of PSDS were limited and it remained unclear whether peripheral inflammation influences the occurrence and development of PSDS. METHODS: A total of 427 prospectively enrolled and followed ischemic stroke patients were included in the analytical sample. Depressive symptomology was assessed on four occasions during 1 year after ischemic stroke. Peripheral inflammatory proteins on admission and repeated measures of peripheral immune markers in three stages were collected. Latent class growth analysis (LCGA) was employed to delineate group-based trajectories of peripheral immune markers and PSDS. Multinomial regression was performed to investigate the association of peripheral inflammation with PSDS trajectories. RESULTS: Four distinct trajectories of PSDS were identified: stable-low (n = 237, 55.5 %), high-remitting (n = 120, 28.1 %), late-onset (n = 44, 10.3 %), and high-persistent (n = 26, 6.1 %) PSDS trajectories. The elevation of peripheral fibrinogen on admission increased the risk of high-persistent PSDS in patients with early high PSDS. Additionally, chronic elevation of innate immune levels might not only increase the risk of high-persistent PSDS in patients with early high PSDS but also increase the risk of late-onset PSDS in patients without early high PSDS. The elevation of adaptive immune levels in the convalescence of ischemic stroke may contribute to the remission of early high PSDS. CONCLUSIONS: Peripheral immunity could influence the development of PSDS, and this influence might have temporal heterogeneity. These results might provide vital clues for the inflammation hypothesis of PSD.

Ischemic stroke outcome after promoting CD4+CD25+ Treg cell migration through CCR4 overexpression in a tMCAO animal model.

The importance of neuroinflammation during the ischemic stroke has been extensively studied. The role of CD4+CD25+ regulatory T (Treg) cells during the recovery phase have shown infarct size reduction and functional improvement, possibly through the mitigation of inflammatory immune responses. We aimed to investigate the molecular factors involved in microglia-Treg cell communication that result in Treg trafficking. First, we observed the migration patterns of CD8+ (cytotoxic) T cells and Treg cells and then searched for chemokines released by activated microglia in an oxygen-glucose deprivation (OGD) model. The transwell migration assay showed increased migration into OGD media for both cell types, in agreement with the increase in chemokines involved in immune cell trafficking from the mouse chemokine profiling array. MSCV retrovirus was transduced to overexpress CCR4 in Treg cells. CCR4-overexpressed Treg cells were injected into the mouse transient middle cerebral artery occlusion (tMCAO) model to evaluate the therapeutic potential via the tetrazolium chloride (TTC) assay and behavioral tests. A general improvement in the prognosis of animals after tMCAO was observed. Our results suggest the increased mobility of CCR4-overexpressed Treg cells in response to microglia-derived chemokines in vitro and the therapeutic potential of Treg cells with increased mobility in cellular therapy.