The Immune Response in Multiple Sclerosis

Therapeutic potential of fucoidan in central nervous system disorders: A systematic review

Central nervous system (CNS) disorders have a complicated pathogenesis, and to date, no single mechanism can fully explain them. Most drugs used for CNS disorders primarily aim to manage symptoms and delay disease progression, and none have demonstrated any pathological reversal. Fucoidan is a safe, sulfated polysaccharide from seaweed that exhibits multiple pharmacological effects, and it is anticipated to be a novel treatment for CNS disorders. To assess the possible clinical uses of fucoidan, this review aims to provide an overview of its neuroprotective mechanism in both in vivo and in vitro CNS disease models, as well as its pharmacokinetics and safety. We included 39 articles on the pharmacology of fucoidan in CNS disorders. In vitro and in vivo experiments demonstrate that fucoidan has important roles in regulating lipid metabolism, enhancing the cholinergic system, maintaining the functional integrity of the blood-brain barrier and mitochondria, inhibiting inflammation, and attenuating oxidative stress and apoptosis, highlighting its potential for CNS disease treatment. Fucoidan has a protective effect against CNS disorders. With ongoing research on fucoidan, it is expected that a natural, highly effective, less toxic, and highly potent fucoidan-based drug or nutritional supplement targeting CNS diseases will be developed.

Integrating genetic and proteomic data to elucidate the association between immune system and blood-brain barrier dysfunction with multiple sclerosis risk and severity

BACKGROUND

Immune system dysfunction and blood-brain barrier (BBB) impairment are implicated in multiple sclerosis (MS) risk and severity. However, the causal relationships and potential therapeutic targets remain unclear.

METHODS

Leveraging the MRC IEU OpenGWAS data infrastructure, we extracted 1254 peripheral immune systems and 792 BBB biomarkers as genetic instruments for exposure. MS risk data from the International Multiple Sclerosis Genetics Consortium (IMSGC) (47,429 MS cases, 68,374 controls) served as one outcome, replicated in FinnGen (1048 cases, 217,141 controls) and the UK Biobank (1679 cases, 461,254 controls). Genetic associations with MS severity derived from IMSGC and MultipleMS Consortium GWAS data (12,584 cases). Two-sample, bidirectional, and protein drug-target MR analyses were conducted, along with interaction analysis of identified proteins and druggability assessment.

RESULTS

Causal relationships between 45 immunological markers, 15 BBB markers, and MS risk were strongly supported. In peripheral immunity, the causal associations with MS are predominantly concentrated in CD4+ T cells and CD8+ T cells. Notably, anti-Epstein-Barr virus nuclear antigen (EBNA) IgG levels exhibited the most significant causal effect on MS risk (OR = 225.62, P = 5.63E-208), replicated in the MS severity (OR = 1.11, P = 0.04). Weak causal evidence was found between 62 immunological markers, 35 BBB markers, and MS severity. Reverse MR analysis suggested potential causal effects of MS risk on 8 markers. Drug-targeted MR analysis indicated potential therapeutic benefits in reducing MS risk for CD40 (OR = 0.71, P = 7.24E-13, PPH4 = 97.6 %), AHSG (OR = 0.88, P = 2.91E-05, PPH4 = 94.4 %), and FCRL3 (Sun BB et al.: OR = 0.83, P = 8.93E-09, PPH4 = 94.2 %, Suhre K et al.: OR = 0.88, P = 5.20E-08, PPH4 = 99.2 %).

CONCLUSIONS

This study provides evidence supporting the causal effects of immune system and BBB dysfunction on MS risk and severity. It emphasizes the significant role of anti-EBNA IgG levels, CD4+ T cells, and CD8+ T cells in MS, and delineates the potential therapeutic benefits of targeting three proteins associated with MS risk: CD40, AHSG, and FCRL3.

Patient and Physician Perspectives of Treatment Burden in Multiple Sclerosis

The number of disease-modifying therapies (DMTs) approved for the treatment of multiple sclerosis (MS) has greatly increased in recent decades, leading to higher treatment complexity. DMTs can differ in mode and frequency of administration, benefit-risk profile, and associated costs. Patients with MS contend not only with the burden of their chronic disease but also with the treatment burden of their MS therapy. Adhering to dosing schedules and infusion appointments can be difficult for busy, working-age patients or those with limited access to transportation. Patients and healthcare professionals (HCPs) may have differing priorities, concerns, and preferences when selecting treatment, potentially affecting treatment satisfaction and, importantly, adherence. Additionally, patients face direct and indirect costs related to treatment. These factors can all contribute to a high treatment burden on patients, impacting their quality of life and potentially leading to worse patient outcomes. HCPs, patients, and caregivers must work together to alleviate treatment burden through effective communication, shared decision-making, appreciating each other's perspectives, and additional HCP support. Consideration of treatment burden into clinical guidelines is also warranted. In this review, we examine key factors impacting treatment burden for patients with MS, with a focus on the patient perspective as provided by our patient authors, and provide strategies to minimize treatment burden.

The role of integrins in brain health and neurodegenerative diseases

Integrins are heterodimeric membrane proteins expressed on the surface of most cells. They mediate adhesion and signaling processes relevant for a wealth of physiological processes, including nervous system development and function. Interestingly, integrins are also recognized therapeutic targets for inflammatory diseases, such as multiple sclerosis. Here, we discuss the role of integrins in brain development and function, as well as in neurodegenerative diseases affecting the brain (Alzheimer's disease, multiple sclerosis, stroke). Furthermore, we discuss therapeutic targeting of these adhesion receptors in inflammatory diseases of the brain.

Single-Cell RNA Sequencing Reveals Transcriptional Landscape of Neutrophils and Highlights the Role of TREM-1 in EAE

BACKGROUND AND OBJECTIVES

Neutrophils, underestimated in multiple sclerosis (MS), are gaining increased attention for their significant functions in patients with MS and the experimental autoimmune encephalomyelitis (EAE) animal model. However, the precise role of neutrophils in cervical lymph nodes (CLNs), the primary CNS-draining lymph nodes where the autoimmune response is initiated during the progression of EAE, remains poorly understood.

METHODS

Applying single-cell RNA sequencing (scRNA-seq), we constructed a comprehensive immune cell atlas of CLNs during development of EAE. Through this atlas, we concentrated on and uncovered the transcriptional landscape, phenotypic and functional heterogeneity of neutrophils, and their crosstalk with immune cells within CLNs in the neuroinflammatory processes in EAE.

RESULTS

Notably, we observed a substantial increase in the neutrophil population in EAE mice, with a particular emphasis on the significant rise within the CLNs. Neutrophils in CLNs were categorized into 3 subtypes, and we explored the specific roles and developmental trajectories of each distinct neutrophil subtype. Neutrophils were found to engage in extensive interactions with other immune cells, playing crucial roles in T-cell activation. Moreover, our findings highlighted the strong migratory ability of neutrophils to CLNs, partly regulated by triggering the receptor expressed on myeloid cells 1 (TREM-1). Inhibiting TREM1 with LR12 prevents neutrophil migration both in vivo and in vitro. In addition, in patients with MS, we confirmed an increase in peripheral neutrophils with an upregulation of TREM-1.

DISCUSSION

Our research provides a comprehensive and precise single-cell atlas of CLNs in EAE, highlighting the role of neutrophils in regulating the periphery immune response. In addition, TREM-1 emerged as an essential regulator of neutrophil migration to CLNs, holding promise as a potential therapeutic target in MS.

NINJ1: A new player in multiple sclerosis pathogenesis and potential therapeutic target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by demyelination. Current treatment options for MS focus on immunosuppression, but their efficacy can be limited. Recent studies suggest a potential role for nerve injury-induced protein 1 (NINJ1) in MS pathogenesis. NINJ1, a protein involved in cell death and inflammation, may contribute to the infiltration and activation of inflammatory cells in the CNS, potentially through enhanced blood-brain barrier crossing; enhancing plasma membrane rupture during cell death, leading to the release of inflammatory mediators and further tissue damage. This review explores the emerging evidence for NINJ1's involvement in MS. It discusses how NINJ1 might mediate the migration of immune cells across the blood-brain barrier, exacerbate neuroinflammation, and participate in plasma membrane rupture-related damage. Finally, the review examines potential therapeutic strategies targeting NINJ1 for improved MS management. Abbreviations: MS, Multiple sclerosis; CNS, Central nervous system; BBB, Blood-brain barrier; GSDMD, Gasdermin-D; EAE, Experimental autoimmune encephalitis; HMGB-1, High mobility group box-1 protein; LDH, Lactate dehydrogenase; PMR, Plasma membrane rupture; DMF, Dimethyl fumarate; DUSP1, Dual-specificity phosphatase 1; PAMPs, Pathogen-associated molecular patterns; DAMPs, Danger-associated molecular patterns; PRRs, Pattern recognition receptors; GM-CSF, Granulocyte-macrophage colony stimulating factor; IFN-γ, Interferon gamma; TNF, Tumor necrosis factor; APCs, Antigen-presenting cells; ECs, Endothelial cells; TGF-β, Transforming growth factor-β; PBMCs, Peripheral blood mononuclear cells; FACS, Fluorescence-activated cell sorting; MCP-1, Monocyte chemoattractant protein-1; NLRP3, Pyrin domain-containing 3; TCR, T cell receptor; ROS, Reactive oxygen species; AP-1, Activator protein-1; ANG1, Angiopoietin 1; BMDMs, Bone marrow-derived macrophages; Arp2/3, actin-related protein 2/3; EMT, epithelial-mesenchymal transition; FAK, focal adhesion kinase; LIMK1, LIM domain kinase 1; PAK1, p21-activated kinases 1; Rac1, Ras-related C3 botulinum toxin substrate 1; β-cat, β-caten; MyD88, myeloid differentiation primary response gene 88; TIRAP, Toll/interleukin-1 receptor domain-containing adapter protein; TLR4, Toll-like receptor 4; IRAKs, interleukin-1 receptor-associated kinases; TRAF6, TNF receptor associated factor 6; TAB2/3, TAK1 binding protein 2/3; TAK1, transforming growth factor-β-activated kinase 1; JNK, c-Jun N-terminal kinase; ERK1/2, Extracellular Signal Regulated Kinase 1/2; IKK, inhibitor of kappa B kinase; IκB, inhibitor of NF-κB; NF-κB, nuclear factor kappa-B; AP-1, activator protein-1; ASC, Apoptosis-associated Speck-like protein containing a CARD; NEK7, NIMA-related kinase 7; NLRP3, Pyrin domain-containing 3; CREB, cAMP response element-binding protein.

Gene expression and alternative splicing analysis in a large-scale Multiple Sclerosis study

Background

Multiple Sclerosis (MS) is an autoimmune neurodegenerative disease affecting approximately 3 million people globally. Despite rigorous research on MS, aspects of its development and progression remain unclear. Understanding molecular mechanisms underlying MS is crucial to providing insights into disease pathways, identifying potential biomarkers for early diagnosis, and revealing novel therapeutic targets for improved patient outcomes.

Methods

We utilized publicly available RNA-seq data (GSE138614) from post-mortem white matter tissues of five donors without any neurological disorder and ten MS patient donors. This data was interrogated for differential gene expression, alternative splicing and single nucleotide variants as well as for functional enrichments in the resulting datasets.

Results

A comparison of non-MS white matter (WM) to MS samples yielded differentially expressed genes involved in adaptive immune response, cell communication, and developmental processes. Genes with expression changes positively correlated with tissue inflammation were enriched in the immune system and receptor interaction pathways. Negatively correlated genes were enriched in neurogenesis, nervous system development, and metabolic pathways. Alternatively spliced transcripts between WM and MS lesions included genes that play roles in neurogenesis, myelination, and oligodendrocyte differentiation, such as brain enriched myelin associated protein ( BCAS1 ), discs large MAGUK scaffold protein 1 ( DLG1 ), KH domain containing RNA binding ( QKI ), and myelin basic protein ( MBP ). Our approach to comparing normal appearing WM (NAWM) and active lesion (AL) from one donor and NAWM and chronic active (CA) tissues from two donors, showed that different IgH and IgK gene subfamilies were differentially expressed. We also identified pathways involved in white matter injury repair and remyelination in these tissues. Differentially spliced genes between these lesions were involved in axon and dendrite structure stability. We also identified exon skipping events and spontaneous single nucleotide polymorphisms in membrane associated ring-CH-type finger 1 ( MARCHF1 ), UDP glycosyltransferase 8 ( UGT8 ), and other genes important in autoimmunity and neurodegeneration.

Conclusion

Overall, we identified unique genes, pathways, and novel splicing events affecting disease progression that can be further investigated as potential novel drug targets for MS treatment.

New views on the complex interplay between degeneration and autoimmunity in multiple sclerosis

Multiple sclerosis (MS) is a frequently disabling neurological disorder characterized by symptoms, clinical signs and imaging abnormalities that typically fluctuate over time, affecting any level of the CNS. Prominent lymphocytic inflammation, many genetic susceptibility variants involving immune pathways, as well as potent responses of the neuroinflammatory component to immunomodulating drugs, have led to the natural conclusion that this disease is driven by a primary autoimmune process. In this Hypothesis and Theory article, we discuss emerging data that cast doubt on this assumption. After three decades of therapeutic experience, what has become clear is that potent immune modulators are highly effective at suppressing inflammatory relapses, yet exhibit very limited effects on the later progressive phase of MS. Moreover, neuropathological examination of MS tissue indicates that degeneration, CNS atrophy, and myelin loss are most prominent in the progressive stage, when lymphocytic inflammation paradoxically wanes. Finally, emerging clinical observations such as "progression independent of relapse activity" and "silent progression," now thought to take hold very early in the course, together argue that an underlying "cytodegenerative" process, likely targeting the myelinating unit, may in fact represent the most proximal step in a complex pathophysiological cascade exacerbated by an autoimmune inflammatory overlay. Parallels are drawn with more traditional neurodegenerative disorders, where a progressive proteopathy with prion-like propagation of toxic misfolded species is now known to play a key role. A potentially pivotal contribution of the Epstein-Barr virus and B cells in this process is also discussed.

2-Bromo-1,4-Naphthalenedione promotes CD8+ T cell expansion and limits Th1/Th17 to mitigate experimental autoimmune encephalomyelitis

Treating Multiple sclerosis (MS), a well-known immune-mediated disease characterized by axonal demyelination, is challenging due to its complex causes. Naphthalenedione, present in numerous plants, is being explored as a potential medicine for MS due to its immunomodulatory properties. However, its effects on lymphocytes can vary depending on factors such as the specific compound, concentration, and experimental conditions. In this study, we aim to explore the therapeutic potential of 2-bromo-1,4-naphthalenedione (BrQ), a derivative of naphthalenedione, in experimental autoimmune encephalomyelitis (EAE), an animal model of MS, and to elucidate its underlying mechanisms. We observed that mice treated with BrQ exhibited reduced severity of EAE symptoms, including lower clinical scores, decreased leukocyte infiltration, and less extensive demyelination in central nervous system. Furthermore, it was noted that BrQ does not directly affect the remyelination process. Through cell-chat analysis based on bulk RNA-seq data, coupled with validation of flow analysis, we discovered that BrQ significantly promotes the expansion of CD8+ T cells and their interactions with other immune cells in peripheral immune system in EAE mice. Subsequent CD8+ T cell depletion experiments confirmed that BrQ alleviates EAE in a CD8+ T cell-dependent manner. Mechanistically, expanded CD8+ cells were found to selectively reduce antigen-specific CD4+ cells and subsequently inhibit Th1 and Th17 cell development in vivo, ultimately leading to relief from EAE. In summary, our findings highlight the crucial role of BrQ in modulating the pathogenesis of MS, suggesting its potential as a novel drug candidate for treating MS and other autoimmune diseases.

The Application Potential of the Regulation of Tregs Function by Irisin in the Prevention and Treatment of Immune-Related Diseases

Irisin is a muscle factor induced by exercise, generated through the proteolytic cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC-5). Numerous studies have shown that irisin plays a significant role in regulating glucose and lipid metabolism, inhibiting oxidative stress, reducing systemic inflammatory responses, and providing neuroprotection. Additionally, irisin can exert immunomodulatory functions by regulating regulatory T cells (Tregs). Tregs are a highly differentiated subset of mature T cells that play a key role in maintaining self-immune homeostasis and are closely related to infections, inflammation, immune-related diseases, and tumors. Irisin exerts persistent positive effects on Treg cell functions through various mechanisms, including regulating Treg cell differentiation and proliferation, improving their function, modulating the balance of immune cells, increasing the production of anti-inflammatory cytokines, and enhancing metabolic functions, thereby helping to maintain immune homeostasis and prevent immune-related diseases. As an important myokine, irisin interacts with receptors on the cell membrane, activating multiple intracellular signaling pathways to regulate cell metabolism, proliferation, and function. Although the specific receptor for irisin has not been fully identified, integrins are considered potential receptors. Irisin activates various signaling pathways, including AMPK, MAPK, and PI3K/Akt, through integrin receptors, thereby exerting multiple biological effects. These research findings provide important clues for understanding the mechanisms of irisin's action and theoretical basis for its potential applications in metabolic diseases and immunomodulation. This article reviews the relationship between irisin and Tregs, as well as the research progress of irisin in immune-related diseases such as multiple sclerosis, myasthenia gravis, acquired immune deficiency syndrome, type 1 diabetes, sepsis, and rheumatoid arthritis. Studies have revealed that irisin plays an important role in immune regulation by improving the function of Tregs, suggesting its potential application value in the treatment of immune-related diseases.

An Overview of Multiple Sclerosis In Vitro Models

Multiple sclerosis (MS) still poses a challenge in terms of complex etiology, not fully effective methods of treatment, and lack of healing agents. This neurodegenerative condition considerably affects the comfort of life by causing difficulties with movement and worsening cognition. Neuron, astrocyte, microglia, and oligodendrocyte activity is engaged in multiple pathogenic processes associated with MS. These cells are also utilized in creating in vitro cellular models for investigations focusing on MS. In this article, we present and discuss a summary of different in vitro models useful for MS research and describe their development. We discuss cellular models derived from animals or humans and present in the form of primary cell lines or immortalized cell lines. In addition, we characterize cell cultures developed from induced pluripotent stem cells (iPSCs). Culture conditions (2D and 3D cultures) are also discussed.

Re-establishing immune tolerance in multiple sclerosis: focusing on novel mechanisms of mesenchymal stem cell regulation of Th17/Treg balance

The T-helper 17 (Th17) cell and regulatory T cell (Treg) axis plays a crucial role in the development of multiple sclerosis (MS), which is regarded as an immune imbalance between pro-inflammatory cytokines and the maintenance of immune tolerance. Mesenchymal stem cell (MSC)-mediated therapies have received increasing attention in MS research. In MS and its animal model experimental autoimmune encephalomyelitis, MSC injection was shown to alter the differentiation of CD4+T cells. This alteration occurred by inducing anergy and reduction in the number of Th17 cells, stimulating the polarization of antigen-specific Treg to reverse the imbalance of the Th17/Treg axis, reducing the inflammatory cascade response and demyelination, and restoring an overall state of immune tolerance. In this review, we summarize the mechanisms by which MSCs regulate the balance between Th17 cells and Tregs, including extracellular vesicles, mitochondrial transfer, metabolic reprogramming, and autophagy. We aimed to identify new targets for MS treatment using cellular therapy by analyzing MSC-mediated Th17-to-Treg polarization.

Identifying Diagnostic Markers and Constructing Predictive Models for Oxidative Stress in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic disease characterized by inflammation and neurodegeneration of the central nervous system. Despite the significant role of oxidative stress in the pathogenesis of MS, its precise molecular mechanisms remain unclear. This study utilized microarray datasets from the GEO database to analyze differentially expressed oxidative-stress-related genes (DE-OSRGs), identifying 101 DE-OSRGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicate that these genes are primarily involved in oxidative stress and immune responses. Through protein-protein interaction (PPI) network, LASSO regression, and logistic regression analyses, four genes (MMP9, NFKBIA, NFKB1, and SRC) were identified as being closely related to MS. A diagnostic prediction model based on logistic regression demonstrated good predictive power, as shown by the nomogram curve index and DAC results. An immune-cell infiltration analysis using CIBERSORT revealed significant correlations between these genes and immune cell subpopulations. Abnormal oxidative stress and upregulated expression of key genes were observed in the blood and brain tissues of EAE mice. A molecular docking analysis suggested strong binding potentials between the proteins of these genes and several drug molecules, including isoquercitrin, decitabine, benztropine, and curcumin. In conclusion, this study identifies and validates potential diagnostic biomarkers for MS, establishes an effective prediction model, and provides new insights for the early diagnosis and personalized treatment of MS.

Methylprednisolone Modulates the Tfr/Tfh ratio in EAE-Induced Neuroinflammation through the PI3K/AKT/FoxO1 and PI3K/AKT/mTOR Signalling Pathways

Methylprednisolone (MP) is a potent glucocorticoid that can effectively inhibit immune system inflammation and brain tissue damage in Multiple sclerosis (MS) patients. T follicular helper (Tfh) cells are a subpopulation of activated CD4 + T cells, while T follicular regulatory (Tfr) cells, a novel subset of Treg cells, possess specialized abilities to suppress the Tfh-GC response and inhibit antibody production. Dysregulation of either Tfh or Tfr cells has been implicated in the pathogenesis of MS. However, the molecular mechanism underlying the anti-inflammatory effects of MP therapy on experimental autoimmune encephalomyelitis (EAE), a representative model for MS, remains unclear. This study aimed to investigate the effects of MP treatment on EAE and elucidate the possible underlying molecular mechanisms involed. We evaluated the effects of MP on disease progression, CNS inflammatory cell infiltration and myelination, microglia and astrocyte activation, as well as Tfr/Tfh ratio and related molecules/inflammatory factors in EAE mice. Additionally, Western blotting was used to assess the expression of proteins associated with the PI3K/AKT pathway. Our findings demonstrated that MP treatment ameliorated clinical symptoms, inflammatory cell infiltration, and myelination. Furthermore, it reduced microglial and astrocytic activation. MP may increase the number of Tfr cells and the levels of cytokine TGF-β1, while reducing the number of Tfh cells and the levels of cytokine IL-21, as well as regulate the imbalanced Tfr/Tfh ratio in EAE mice. The PI3K/AKT/FoxO1 and PI3K/AKT/mTOR pathways were found to be involved in EAE development. However, MP treatment inhibited their activation. MP reduced neuroinflammation in EAE by regulating the balance between Tfr/Tfh cells via inhibition of the PI3K/AKT/FoxO1 and PI3K/AKT/mTOR signalling pathways.

Decoding the role of the CCL2/CCR2 axis in Alzheimer's disease and innovating therapeutic approaches: Keeping All options open

Alzheimer's disease (AD), as a neurodegenerative disorder, distresses the elderly in large numbers and is characterized by β-amyloid (Aβ) accumulation, elevated tau protein levels, and chronic inflammation. The brain's immune system is aided by microglia and astrocytes, which produce chemokines and cytokines. Nevertheless, dysregulated expression can cause hyperinflammation and lead to neurodegeneration. CCL2/CCR2 chemokines are implicated in neurodegenerative diseases exacerbating. Inflicting damage on nerves and central nervous system (CNS) cells is the function of this axis, which recruits and migrates immune cells, including monocytes and macrophages. It has been shown that targeting the CCL2/CCR2 axis may be a therapeutic option for inflammatory diseases. Using the current knowledge about the involvement of the CCL2/CCR2 axis in the immunopathogenesis of AD, this comprehensive review synthesizes existing information. It also explores potential therapeutic options, including modulation of the CCL2/CCR2 axis as a possible strategy in AD.

Crucial Roles of RSAD2/viperin in Immunomodulation, Mitochondrial Metabolism and Autoimmune Diseases

Autoimmune diseases are typically characterized by aberrant activation of immune system that leads to excessive inflammatory reactions and tissue damage. Nevertheless, precise targeted and efficient therapies are limited. Thus, studies into novel therapeutic targets for the management of autoimmune diseases are urgently needed. Radical S-adenosyl methionine domain-containing 2 (RSAD2) is an interferon-stimulated gene (ISG) renowned for the antiviral properties of the protein it encodes, named viperin. An increasing number of studies have underscored the new roles of RSAD2/viperin in immunomodulation and mitochondrial metabolism. Previous studies have shown that there is a complex interplay between RSAD2/vipeirn and mitochondria and that binding of the iron-sulfur (Fe-S) cluster is necessary for the involvement of viperin in mitochondrial metabolism. Viperin influences the proliferation and development of immune cells as well as inflammation via different signaling pathways. However, the function of RSAD2/viperin varies in different studies and a comprehensive overview of this emerging theme is lacking. This review will describe the characteristics of RSAD2/viperin, decipher its function in immunometabolic processes, and clarify the crosstalk between RSAD2/viperin and mitochondria. Furthermore, we emphasize the crucial roles of RSAD2 in autoimmune diseases and its potential application value.

Establishment of the Diagnostic Signature of Ferroptosis Genes in Multiple Sclerosis

Ferroptosis is a novel form of membrane-dependent cell death that differs from other cell death modalities such as necrosis, apoptosis, and autophagy. Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system primarily affecting brain and spinal cord neurons. Although the pathogenesis of these two conditions may seem unrelated, recent studies have indicated a connection between ferroptosis and multiple sclerosis. In fact, ferroptosis plays a significant role in the development of MS, as evidenced by the presence of elevated iron levels and iron metabolism abnormalities in the brains, spinal cords, and other neurons of MS patients. These abnormalities disrupt iron homeostasis within cells, leading to the occurrence of ferroptosis. However, there is currently a lack of research on the diagnostic value of ferroptosis-related genes in multiple sclerosis. In this study, we employed bioinformatics methods to identify ferroptosis-related genes (ATM, GSK3B, HMGCR, KLF2, MAPK1, NFE2L1, NRAS, PCBP1, PIK3CA, RPL8, VDAC3) associated with the diagnosis of multiple sclerosis and constructed a diagnostic model. The results demonstrated that the diagnostic model accurately identified the patients' condition. Subsequently, subgroup analysis was performed based on the expression levels of ferroptosis-related genes, dividing patients into high and low expression groups. The results showed differences in immune function and immune cell infiltration between the two groups. Our study not only confirms the correlation between ferroptosis and multiple sclerosis but also demonstrates the diagnostic value of ferroptosis-related genes in the disease. This provides guidance for clinical practice and direction for further mechanistic research.

Hederagenol improves multiple sclerosis by modulating Th17 cell differentiation

Multiple sclerosis (MS) is a common autoimmune illness that is difficult to treat. The upregulation of Th17 cells is critical in the pathological process of MS. Hederagenol (Hed) has been shown to lower IL-17 levels, although its role in MS pathophysiology is uncertain. In this study, we explore whether Hed could ameliorate MS by modulating Th17 cell differentiation, with the goal of identifying new treatment targets for MS. The experimental autoimmune encephalomyelitis (EAE) mouse model was conducted and Hed was intraperitoneally injected into mice. The weight was recorded and the clinical symptom grade was assessed. Hematoxylin-eosin staining was carried out to determine the extent of inflammation in the spinal cord and liver. The luxol Fast Blue staining was performed to detect the pathological changes in the myelin sheath. Nerve damage was detected using NeuN immunofluorescence staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Immunohistology approaches were used to study alterations in immune cells in the spinal cord. The proportions of T cell subsets in the spleens were analyzed by flow cytometry. RORγt levels were measured using quantitative real-time PCR or Western blot. The activity of the RORγt promoter was analyzed by Chromatin immunoprecipitation. Hed administration reduced the clinical symptom grade of EAE mice, as well as the inflammatory infiltration, demyelination, and cell disorder of the spinal cord, while having no discernible effect on the mouse weight. In addition, Hed treatment significantly reduced the number of T cells, particularly Th17 cells in the spinal cord and spleen-isolated CD4+ T cells. Hed lowered the RORγt levels in spleens and CD4+ T cells and overexpression of RORγt reversed the inhibitory effect of Hed on Th17 differentiation. Hed decreased nerve injury by modulating Th17 differentiation through the RORγt promoter. Hed regulates Th17 differentiation by reducing RORγt promoter activity, which reduces nerve injury and alleviates EAE.

Exploring the Therapeutic Potential: Bioactive Molecules and Dietary Interventions in Multiple Sclerosis Management

Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system, the etiology of which is still unclear. Its hallmarks are inflammation and axonal damage. As a disease primarily impacting younger individuals, the social cost of MS is high. It has been proposed that environmental factors, smoking, and dietary habits acting on a genetic susceptibility play a role in MS. Recent studies indicate that diet can significantly influence the onset and progression of MS. This review delves into the impact of natural bioactive molecules on MS development and explores the dietary interventions that hold promise in managing the disease. Dietary patterns, including ketogenic and Mediterranean diets, are discussed. Theories about the potential mechanistic associations beneath the noted effects are also proposed. Several dietary components and patterns demonstrated the potential for a significant impact on MS. However, extensive prospective clinical trials are necessary to fully understand the role of natural bioactive molecules as disease modifiers in MS.

Differential gene expression in B cells and T helper cells following high-dose glucocorticoid therapy for multiple sclerosis relapse

BACKGROUND

Despite remarkable advances in the therapy of multiple sclerosis (MS), patients with MS may still experience relapses. High-dose short-term methylprednisolone (MP) remains the standard treatment in the acute management of MS relapses due to its potent anti-inflammatory and immunosuppressive properties. However, there is a lack of studies on the cell type-specific transcriptome changes that are induced by this synthetic glucocorticoid (GC). Moreover, it is not well understood why some patients do not benefit adequately from MP therapy.

METHODS

We collected peripheral blood from MS patients in relapse immediately before and after ∼3-5 days of therapy with MP at 4 study centers. CD19+ B cells and CD4+ T cells were then isolated for profiling the transcriptome with high-density arrays. The patients' improvement of neurological symptoms was evaluated after ∼2 weeks by the treating physicians. We finally analyzed the data to identify genes that were differentially expressed in response to the therapy and whose expression differed between clinical responders and non-responders.

RESULTS

After MP treatment, a total of 33 genes in B cells and 55 genes in T helper cells were significantly up- or downregulated. The gene lists overlap in 10 genes and contain genes that have already been described as GC-responsive genes in the literature on other cell types and diseases. Their differential expression points to a rapid and coordinated modulation of multiple signaling pathways that influence transcription. Genes that were previously suggested as potential prognostic biomarkers of the clinical response to MP therapy could not be confirmed in our data. However, a greater increase in the expression of genes encoding proteins with antimicrobial activity was detected in CD4+ T cells from non-responders compared to responders.

CONCLUSION

Our study delved into the cell type-specific effects of MP at the transcriptional level. The data suggest a therapy-induced ectopic expression of some genes (e.g., AZU1, ELANE and MPO), especially in non-responders. The biological consequences of this remain to be explored in greater depth. A better understanding of the molecular mechanisms underlying clinical recovery from relapses in patients with MS will help to optimize future treatment decisions.

Sex- and species-specific contribution of CD99 to T cell costimulation during multiple sclerosis

BACKGROUND

Differences in immune responses between women and men are leading to a strong sex bias in the incidence of autoimmune diseases that predominantly affect women, such as multiple sclerosis (MS). MS manifests in more than twice as many women, making sex one of the most important risk factor. However, it is incompletely understood which genes contribute to sex differences in autoimmune incidence. To address that, we conducted a gene expression analysis in female and male human spleen and identified the transmembrane protein CD99 as one of the most significantly differentially expressed genes with marked increase in men. CD99 has been reported to participate in immune cell transmigration and T cell regulation, but sex-specific implications have not been comprehensively investigated.

METHODS

In this study, we conducted a gene expression analysis in female and male human spleen using the Genotype-Tissue Expression (GTEx) project dataset to identify differentially expressed genes between women and men. After successful validation on protein level of human immune cell subsets, we assessed hormonal regulation of CD99 as well as its implication on T cell regulation in primary human T cells and Jurkat T cells. In addition, we performed in vivo assays in wildtype mice and in Cd99-deficient mice to further analyze functional consequences of differential CD99 expression.

RESULTS

Here, we found higher CD99 gene expression in male human spleens compared to females and confirmed this expression difference on protein level on the surface of T cells and pDCs. Androgens are likely dispensable as the cause shown by in vitro assays and ex vivo analysis of trans men samples. In cerebrospinal fluid, CD99 was higher on T cells compared to blood. Of note, male MS patients had lower CD99 levels on CD4+ T cells in the CSF, unlike controls. By contrast, both sexes had similar CD99 expression in mice and Cd99-deficient mice showed equal susceptibility to experimental autoimmune encephalomyelitis compared to wildtypes. Functionally, CD99 increased upon human T cell activation and inhibited T cell proliferation after blockade. Accordingly, CD99-deficient Jurkat T cells showed decreased cell proliferation and cluster formation, rescued by CD99 reintroduction.

CONCLUSIONS

Our results demonstrate that CD99 is sex-specifically regulated in healthy individuals and MS patients and that it is involved in T cell costimulation in humans but not in mice. CD99 could potentially contribute to MS incidence and susceptibility in a sex-specific manner.

Role of ferroptosis in neuroimmunity and neurodegeneration in multiple sclerosis revealed by multi-omics data

Previous studies have found that ferroptosis plays an important role in a variety of neurological diseases. However, the precise role of ferroptosis in the multiple sclerosis patients remains uncertain. We defined and validated a computational metric of ferroptosis levels. The ferroptosis scores were computed using the AUCell method, which reflects the enrichment scores of ferroptosis-related genes through gene ranking. The reliability of the ferroptosis score was assessed using various methods, involving cells induced to undergo ferroptosis by six different ferroptosis inducers. Through a comprehensive approach integrating snRNA-seq, spatial transcriptomics, and spatial proteomics data, we explored the role of ferroptosis in multiple sclerosis. Our findings revealed that among seven sampling regions of different white matter lesions, the edges of active lesions exhibited the highest ferroptosis score, which was associated with activation of the phagocyte system. Remyelination lesions exhibit the lowest ferroptosis score. In the cortex, ferroptosis score were elevated in neurons, relevant to a variety of neurodegenerative disease-related pathways. Spatial transcriptomics demonstrated a significant co-localization among ferroptosis score, neurodegeneration and microglia, which was verified by spatial proteomics. Furthermore, we established a diagnostic model of multiple sclerosis based on 24 ferroptosis-related genes in the peripheral blood. Ferroptosis might exhibits a dual role in the context of multiple sclerosis, relevant to both neuroimmunity and neurodegeneration, thereby presenting a promising and novel therapeutic target. Ferroptosis-related genes in the blood that could potentially serve as diagnostic and prognostic markers for multiple sclerosis.

Influence of STAT4 Genetic Variants and Serum Levels on Multiple Sclerosis Occurrence in the Lithuanian Population

Background: Multiple sclerosis (MS) is an autoimmune disease involving demyelination, inflammation, gliosis, and the loss of neurons. MS is a growing global health problem most likely caused by genetic, immunological, and environmental factors. However, the exact etiology of the disease is still unknown. Since MS is related to a dysregulation of the immune system, it could be linked to signal transducer and activator of transcription 4 (STAT4). To fully comprehend the significance of the STAT4 gene and STAT4 serum levels in MS, further research is required. Methods: A total of 200 MS patients and 200 healthy controls participated in the study. Deoxyribonucleic acid (DNA) was extracted using silica-based membrane technology. Polymerase chain reaction was used in real time for genotyping. Using the ELISA technique, serum levels were measured. Results:STAT4 rs7601754 AA genotype and the A allele were statistically significantly less frequent in MS patients (p = 0.003). Also, rs7601754 was associated with 1.9-fold increased odds of MS occurrence (p = 0.004). The rs7601754 AG genotype was more common in males with MS (p = 0.011) and was associated with 2.5-fold increased odds of MS occurrence in males (p = 0.012). STAT4 serum levels were statistically significantly lower in MS patients compared to the control group (p = 0.007). Conclusions:STAT4 rs7601754 increases the odds of MS occurrence. STAT4 serum levels were statistically significantly lower in MS patients compared to the control group.

Neuroinflammation and Epilepsy: From Pathophysiology to Therapies Based on Repurposing Drugs

Neuroinflammation and epilepsy are different pathologies, but, in some cases, they are so closely related that the activation of one of the pathologies leads to the development of the other. In this work, we discuss the three main cell types involved in neuroinflammation, namely (i) reactive astrocytes, (ii) activated microglia, and infiltration of (iii) peripheral immune cells in the central nervous system. Then, we discuss how neuroinflammation and epilepsy are interconnected and describe the use of different repurposing drugs with anti-inflammatory properties that have been shown to have a beneficial effect in different epilepsy models. This review reinforces the idea that compounds designed to alleviate seizures need to target not only the neuroinflammation caused by reactive astrocytes and microglia but also the interaction of these cells with infiltrated peripheral immune cells.

Immunological aspects of central neurodegeneration

The etiology of various neurodegenerative disorders that mainly affect the central nervous system including (but not limited to) Alzheimer's disease, Parkinson's disease and Huntington's disease has classically been attributed to neuronal defects that culminate with the loss of specific neuronal populations. However, accumulating evidence suggests that numerous immune effector cells and the products thereof (including cytokines and other soluble mediators) have a major impact on the pathogenesis and/or severity of these and other neurodegenerative syndromes. These observations not only add to our understanding of neurodegenerative conditions but also imply that (at least in some cases) therapeutic strategies targeting immune cells or their products may mediate clinically relevant neuroprotective effects. Here, we critically discuss immunological mechanisms of central neurodegeneration and propose potential strategies to correct neurodegeneration-associated immunological dysfunction with therapeutic purposes.

Relapsing-remitting multiple sclerosis patients exhibit differential natural killer functional subpopulations

BACKGROUND

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) and has been known as T-cell mediated. However, the contribution of multiple cell types, notably natural killer (NK) cells, has also been reported.

AIM

To quantify circulating total NK cells and its subpopulations, CD56 dim and bright, and to characterize the functional phenotype and IFN-γ and TNF-α production in relapsing-remitting patients treated with IFN-β and in apparently healthy controls.

RESULTS

CD56bright NK cells were found to be the least represented subpopulation. In relapse patients, the frequencies of IFN-γ-producing NK cells and their subpopulations were significantly decreased. In remission patients, CD56dim NK cells expressed high levels of HLA-DR and CD54.

CONCLUSION

These results suggest that remission RRMS patients, although in an inactive stage of MS, present circulating NK cells with an activation phenotype, supporting the idea that NK cells may be relevant mediators in the MS pathophysiology.

Vibrational spectroscopy and multiphoton microscopy for label-free visualization of nervous system degeneration and regeneration

Neurological disorders, including spinal cord injury, peripheral nerve injury, traumatic brain injury, and neurodegenerative diseases, pose significant challenges in terms of diagnosis, treatment, and understanding the underlying pathophysiological processes. Label-free multiphoton microscopy techniques, such as coherent Raman scattering, two-photon excited autofluorescence, and second and third harmonic generation microscopy, have emerged as powerful tools for visualizing nervous tissue with high resolution and without the need for exogenous labels. Coherent Raman scattering processes as well as third harmonic generation enable label-free visualization of myelin sheaths, while their combination with two-photon excited autofluorescence and second harmonic generation allows for a more comprehensive tissue visualization. They have shown promise in assessing the efficacy of therapeutic interventions and may have future applications in clinical diagnostics. In addition to multiphoton microscopy, vibrational spectroscopy methods such as infrared and Raman spectroscopy offer insights into the molecular signatures of injured nervous tissues and hold potential as diagnostic markers. This review summarizes the application of these label-free optical techniques in preclinical models and illustrates their potential in the diagnosis and treatment of neurological disorders with a special focus on injury, degeneration, and regeneration. Furthermore, it addresses current advancements and challenges for bridging the gap between research findings and their practical applications in a clinical setting.

CCR5 and inflammatory storm

Chemokines and their corresponding receptors play crucial roles in orchestrating inflammatory and immune responses, particularly in the context of pathological conditions disrupting the internal environment. Among these receptors, CCR5 has garnered considerable attention due to its significant involvement in the inflammatory cascade, serving as a pivotal mediator of neuroinflammation and other inflammatory pathways associated with various diseases. However, a notable gap persists in comprehending the intricate mechanisms governing the interplay between CCR5 and its ligands across diverse and intricate inflammatory pathologies. Further exploration is warranted, especially concerning the inflammatory cascade instigated by immune cell infiltration and the precise binding sites within signaling pathways. This study aims to illuminate the regulatory axes modulating signaling pathways in inflammatory cells by providing a comprehensive overview of the pathogenic processes associated with CCR5 and its ligands across various disorders. The primary focus lies on investigating the pathomechanisms associated with CCR5 in disorders related to neuroinflammation, alongside the potential impact of aging on these processes and therapeutic interventions. The discourse culminates in addressing current challenges and envisaging potential future applications, advocating for innovative research endeavors to advance our comprehension of this realm.

Identification of Y‒linked biomarkers and exploration of immune infiltration of normal-appearing gray matter in multiple sclerosis by bioinformatic analysis

Background

The knowledge of normal‒appearing cortical gray matter (NAGM) in multiple sclerosis (MS) remains unclear. In this study, we aimed to identify diagnostic biomarkers and explore the immune infiltration characteristics of NAGM in MS through bioinformatic analysis and validation in vivo.

Methods

Differentially expressed genes (DEGs) were analyzed. Subsequently, the functional pathways of the DEGs were determined. After screening the overlapping DEGs of MS with two machine learning methods, the biomarkers' efficacy and the expression levels of overlapping DEGs were calculated. Quantitative reverse transcription polymerase chain reaction (qRT‒PCR) identified the robust diagnostic biomarkers. Additionally, infiltrating immune cell populations were estimated and correlated with the biomarkers. Finally, the characteristics of immune infiltration of NAGM from MS were evaluated.

Results

A total of 98 DEGs were identified. They participated in sensory transduction of the olfactory system, synaptic signaling, and immune responses. Nine overlapping genes were screened by machine learning methods. After verified by ROC curve, four genes, namely HLA‒DRB1, RPS4Y1, EIF1AY and USP9Y, were screened as candidate biomarkers. The mRNA expression of RPS4Y1 and USP9Y was significantly lower in MS patients than that in the controls. They were selected as the robust diagnostic biomarkers for male MS patients. RPS4Y1 and USP9Y were both positively correlated with memory B cells. Moreover, naive CD4+ T cells and monocytes were increased in the NAGM of MS patients compared with those in controls.

Conclusions

Low expressed Y‒linked genes, RPS4Y1 and USP9Y, were identified as diagnostic biomarkers for MS in male patients. The inhomogeneity of immune cells in NAGM might exacerbate intricate interplay between the CNS and the immune system in the MS.

Immune cells: potential carriers or agents for drug delivery to the central nervous system

Drug delivery systems (DDS) have recently emerged as a promising approach for the unique advantages of drug protection and targeted delivery. However, the access of nanoparticles/drugs to the central nervous system (CNS) remains a challenge mainly due to the obstruction from brain barriers. Immune cells infiltrating the CNS in the pathological state have inspired the development of strategies for CNS foundation drug delivery. Herein, we outline the three major brain barriers in the CNS and the mechanisms by which immune cells migrate across the blood-brain barrier. We subsequently review biomimetic strategies utilizing immune cell-based nanoparticles for the delivery of nanoparticles/drugs to the CNS, as well as recent progress in rationally engineering immune cell-based DDS for CNS diseases. Finally, we discuss the challenges and opportunities of immune cell-based DDS in CNS diseases to promote their clinical development.

CD4+CD25+ regulatory T cells ex vivo generated from autologous naïve CD4+ T cells suppress EAE progression

CD4+CD25+ regulatory T cells (Tregs) play an important role in maintaining immune homeostasis in multiple sclerosis (MS). Hence, we aimed to explore the therapeutic efficacy and safety of adoptive cell therapy (ACT) utilizing induced antigen-specific Tregs in an animal model of MS, that is, in an experimental autoimmune encephalomyelitis (EAE) model. B cells from EAE model that were activated with soluble CD40L were used as antigen-presenting cells (APCs) to induce the differentiation of antigen-specific Tregs from naïve CD4 precursors, and then, a stepwise isolation of CD4+CD25highCD127low Tregs was performed using a flow sorter. All EAE mice were divided into Treg-treated group (2 × 104 cells in 0.2 mL per mouse, n = 14) and sham-treated group (0.2 mL normal saline (NS), n = 20), which were observed daily for clinical assessment, and for abnormal appearance for 6 weeks. Afterward, histological analysis, immunofluorescence and real-time PCR were performed. Compared to sham-treated mice, Treg-treated mice exhibited a significant decrease in disease severity scores and reduced inflammatory infiltration and demyelination in the spinal cord. Additionally, Tregs-treated mice demonstrated higher CCN3 protein and mRNA levels than sham-treated mice. The results of this preclinical study further support the therapeutic potential of this ACT approach in the treatment of MS.

Proximity extension assay-based proteomics studies in neurodegenerative disorders and multiple sclerosis

Neurodegenerative diseases impact the structure and operation of the nervous system, causing progressive and irreparable harm. Efforts for distinguishing neurodegenerative diseases in their early stages are continuing. Despite several biomarkers being identified, there is always search for more accurate and abundant ones. Additionally, it can be difficult to pinpoint the precise neurodegenerative disorder affecting a patient as the symptoms of these conditions frequently overlap. Numerous studies have shown that pathological changes occur years before clinical signs appear. Therefore, it is crucial to discover blood-based biomarkers for neurodegenerative diseases for easier and earlier diagnosis. Proximity extension assay is a unique proteomics method that uses antibodies linked to oligonucleotides for quantifying proteins with real-time PCR. Proximity extension assay can identify even low-quantity proteins using a small volume of specimens with increased sensitivity compared to conventional methods. In this article, we reviewed the employment of proximity extension assay technology to detect biomarkers or protein profiles for several neurodegenerative diseases.

Assessing robustness and generalization of a deep neural network for brain MS lesion segmentation on real-world data

OBJECTIVES

Evaluate the performance of a deep learning (DL)-based model for multiple sclerosis (MS) lesion segmentation and compare it to other DL and non-DL algorithms.

METHODS

This ambispective, multicenter study assessed the performance of a DL-based model for MS lesion segmentation and compared it to alternative DL- and non-DL-based methods. Models were tested on internal (n = 20) and external (n = 18) datasets from Latin America, and on an external dataset from Europe (n = 49). We also examined robustness by rescanning six patients (n = 6) from our MS clinical cohort. Moreover, we studied inter-human annotator agreement and discussed our findings in light of these results. Performance and robustness were assessed using intraclass correlation coefficient (ICC), Dice coefficient (DC), and coefficient of variation (CV).

RESULTS

Inter-human ICC ranged from 0.89 to 0.95, while spatial agreement among annotators showed a median DC of 0.63. Using expert manual segmentations as ground truth, our DL model achieved a median DC of 0.73 on the internal, 0.66 on the external, and 0.70 on the challenge datasets. The performance of our DL model exceeded that of the alternative algorithms on all datasets. In the robustness experiment, our DL model also achieved higher DC (ranging from 0.82 to 0.90) and lower CV (ranging from 0.7 to 7.9%) when compared to the alternative methods.

CONCLUSION

Our DL-based model outperformed alternative methods for brain MS lesion segmentation. The model also proved to generalize well on unseen data and has a robust performance and low processing times both on real-world and challenge-based data.

CLINICAL RELEVANCE STATEMENT

Our DL-based model demonstrated superior performance in accurately segmenting brain MS lesions compared to alternative methods, indicating its potential for clinical application with improved accuracy, robustness, and efficiency.

KEY POINTS

• Automated lesion load quantification in MS patients is valuable; however, more accurate methods are still necessary. • A novel deep learning model outperformed alternative MS lesion segmentation methods on multisite datasets. • Deep learning models are particularly suitable for MS lesion segmentation in clinical scenarios.

Volumetric and Asymmetric Index Analysis of Subcortical Structures in Multiple Sclerosis Patients: A Retrospective Study Using volBrain Software

Introduction Multiple sclerosis (MS) is a chronic and autoimmune disease that has a significant influence on the central nervous system, such as the brain and spinal cord, affecting millions of individuals globally. Understanding the connection between subcortical brain regions and MS is crucial for effective diagnostic and therapeutic approaches for treating this disabling disease. This study explores the relationship between volume and contours of asymmetry index of subcortical brain regions in individuals with MS using volBrain software (https://www.volbrain.net; developed by José V. Manjón (Valencia Polytechnic University, Valencia, Spain) and Pierrick Coupé (University of Bordeaux, Bordeaux, France)). Methods In our retrospective investigation, we admitted 100 Turkish individuals, comprising 50 patients diagnosed with relapsing-remitting MS (RRMS) (24 (48%) males and 26 (52%) females) and 50 healthy controls (23 (46%) males and 27 (54%) females), registered between October 2017 and February 2022 for five years and underwent assessment in the radiology department at the Teaching and Research Hospital of Kocaeli University; 1,150 Turkish patients were excluded from our study based on our exclusion criteria. We used magnetic resonance imaging with a 3-Tesla (3T) scanner and volBrain software to assess volumes (cm3) and asymmetry indexes due to asymmetry for different levels of atrophy of total intracranial, total brain, gray matter, white matter, and subcortical regions, the most affected regions in MS patients for both patient and control cohorts. Results Statistical analysis revealed a significant difference between patient and control groups (p < 0.001), with patient group mean age at 38.32 years and control group mean age at 32.88 years. Patient group exhibited lower values for total intracranial, total brain, gray matter, white matter, and cerebrospinal fluid volume compared to control group (p < 0.05). The results indicated a statistically significant decrease (p < 0.05) in the values for total intracranial and total brain volume, whereas all other values remained unchanged. We compared volumes of subcortical structures on the right and left sides and found that the putamen, thalamus, and globus pallidus had statistically lower values in the patient group than in the control group (p < 0.001), apart from the lateral ventricle. Furthermore, our retrospective investigation demonstrated a statistically significant difference in the globus pallidus asymmetry index, indicating a preference for the patient group (p < 0.05). A lower asymmetry index value signifies a larger volume for the right side of the subcortical regions of the brain when compared to the left side. Conclusion Brain atrophy, although characterized by irreversible tissue damage, is targeted by therapeutic interventions to prevent progression. It is, therefore, imperative to develop a universally accepted measurement standard for subcortical structures that also considers the inherent variability present within each structure. Our findings serve as an important basis and indicator for the determination of subcortical atrophy and asymmetry in MS, the prognosis of the disease, and the etiology of clinical symptoms. Subsequent research may benefit by adopting the novel approach of considering brain atrophy as an outcome rather than a predictor, thereby facilitating the elucidation of the intricate biological mechanisms that give rise to volume loss.

The Utility of Miniaturized Adsorbers in Exploring the Cellular and Molecular Effects of Blood Purification: A Pilot Study with a Focus on Immunoadsorption in Multiple Sclerosis

Immunoadsorption (IA) has proven to be clinically effective in the treatment of steroid-refractory multiple sclerosis (MS) relapses, but its mechanism of action remains unclear. We used miniaturized adsorber devices with a tryptophan-immobilized polyvinyl alcohol (PVA) gel sorbent to mimic the IA treatment of patients with MS in vitro. The plasma was screened before and after adsorption with regard to disease-specific mediators, and the effect of the IA treatment on the migration of neutrophils and the integrity of the endothelial cell barrier was tested in cell-based models. The in vitro IA treatment with miniaturized adsorbers resulted in reduced plasma levels of cytokines and chemokines. We also found a reduced migration of neutrophils towards patient plasma treated with the adsorbers. Furthermore, the IA-treated plasma had a positive effect on the endothelial cell barrier's integrity in the cell culture model. Our findings suggest that IA results in a reduced infiltration of cells into the central nervous system by reducing leukocyte transmigration and preventing blood-brain barrier breakdown. This novel approach of performing in vitro blood purification therapies on actual patient samples with miniaturized adsorbers and testing their effects in cell-based assays that investigate specific hypotheses of the pathophysiology provides a promising platform for elucidating the mechanisms of action of those therapies in various diseases.

Causal association between the peripheral immunity and the risk and disease severity of multiple sclerosis

Background

Growing evidence links immunological responses to Multiple sclerosis (MS), but specific immune factors are still unclear.

Methods

Mendelian randomization (MR) was performed to investigate the association between peripheral hematological traits, MS risk, and its severity. Then, further subgroup analysis of immune counts and circulating cytokines and growth factors were performed.

Results

MR revealed higher white blood cell count (OR [95%CI] = 1.26 [1.10,1.44], P = 1.12E-03, P adjust = 3.35E-03) and lymphocyte count (OR [95%CI] = 1.31 [1.15,1.50], P = 5.37E-05, P adjust = 3.22E-04) increased the risk of MS. In further analysis, higher T cell absolute count (OR [95%CI] = 2.04 [1.36,3.08], P = 6.37E-04, P adjust = 2.19E-02) and CD4+ T cell absolute count (OR [95%CI] = 2.11 [1.37,3.24], P = 6.37E-04, P adjust = 2.19E-02), could increase MS risk. While increasing CD25++CD4+ T cell absolute count (OR [95%CI] = 0.75 [0.66,0.86], P = 2.12E-05, P adjust = 1.72E-03), CD25++CD4+ T cell in T cell (OR [95%CI] = 0.79[0.70,0.89], P = 8.54E-05, P adjust = 5.29E-03), CD25++CD4+ T cell in CD4+ T cell (OR [95%CI] = 0.80[0.72,0.89], P = 1.85E-05, P adjust = 1.72E-03), and CD25++CD8+ T cell in T cell (OR [95%CI] = 0.68[0.57,0.81], P = 2.22E-05, P adjust = 1.72E-03), were proved to be causally defensive for MS. For the disease severity, the suggestive association between some traits related to CD4+ T cell, Tregs and MS severity were demonstrated. Moreover, elevated levels of IL-2Ra had a detrimental effect on the risk of MS (OR [95%CI] = 1.22 [1.12,1.32], P = 3.20E-06, P adjust = 1.34E-04).

Conclusions

This study demonstrated a genetically predicted causal relationship between elevated peripheral immune cell counts and MS. Subgroup analysis revealed a specific contribution of peripheral immune cells, holding potential for further investigations into the underlying mechanisms of MS and its severity.

LILRB4 Checkpoint for Immunotherapy: Structure, Mechanism and Disease Targets

LILRB4, a myeloid inhibitory receptor belonging to the family of leukocyte immunoglobulin-like receptors (LILRs/LIRs), plays a pivotal role in the regulation of immune tolerance. LILRB4 primarily mediates suppressive immune responses by transmitting inhibitory signals through immunoreceptor tyrosine-based inhibitory motifs (ITIMs). This immune checkpoint molecule has gained considerable attention due to its potent regulatory functions. Its ability to induce effector T cell dysfunction and promote T suppressor cell differentiation has been demonstrated, indicating the therapeutic potential of LILRB4 for modulating excessive immune responses, particularly in autoimmune diseases or the induction of transplant tolerance. Additionally, through intervening with LILRB4 molecules, immune system responsiveness can be adjusted, representing significant value in areas such as cancer treatment. Thus, LILRB4 has emerged as a key player in addressing autoimmune diseases, transplant tolerance induction, and other medical issues. In this review, we provide a comprehensive overview of LILRB4, encompassing its structure, expression, and ligand molecules as well as its role as a tolerance receptor. By exploring the involvement of LILRB4 in various diseases, its significance in disease progression is emphasized. Furthermore, we propose that the manipulation of LILRB4 represents a promising immunotherapeutic strategy and highlight its potential in disease prevention, treatment and diagnosis.

Single-cell transcriptomics analysis of cellular heterogeneity and immune mechanisms in neurodegenerative diseases

Single-cell transcriptomics analysis is an advanced technology that can describe the intracellular transcriptome in complex tissues. It profiles and analyses datasets by single-cell RNA sequencing. Neurodegenerative diseases are identified by the abnormal apoptosis of neurons in the brain with few or no effective therapy strategies at present, which has been a growing healthcare concern and brought a great burden to society. The transcriptome of individual cells provides deep insights into previously unforeseen cellular heterogeneity and gene expression differences in neurodegenerative disorders. It detects multiple cell subsets and functional changes during pathological progression, which deepens the understanding of the molecular underpinnings and cellular basis of neurodegenerative diseases. Furthermore, the transcriptome analysis of immune cells shows the regulation of immune response. Different subtypes of immune cells and their interaction are found to contribute to disease progression. This finding enables the discovery of novel targets and biomarkers for early diagnosis. In this review, we emphasize the principles of the technology, and its recent progress in the study of cellular heterogeneity and immune mechanisms in neurodegenerative diseases. The application of single-cell transcriptomics analysis in neurodegenerative disorders would help explore the pathogenesis of these diseases and develop novel therapeutic methods.

Multiscale networks in multiple sclerosis

Complex diseases such as Multiple Sclerosis (MS) cover a wide range of biological scales, from genes and proteins to cells and tissues, up to the full organism. In fact, any phenotype for an organism is dictated by the interplay among these scales. We conducted a multilayer network analysis and deep phenotyping with multi-omics data (genomics, phosphoproteomics and cytomics), brain and retinal imaging, and clinical data, obtained from a multicenter prospective cohort of 328 patients and 90 healthy controls. Multilayer networks were constructed using mutual information for topological analysis, and Boolean simulations were constructed using Pearson correlation to identified paths within and among all layers. The path more commonly found from the Boolean simulations connects protein MK03, with total T cells, the thickness of the retinal nerve fiber layer (RNFL), and the walking speed. This path contains nodes involved in protein phosphorylation, glial cell differentiation, and regulation of stress-activated MAPK cascade, among others. Specific paths identified were subsequently analyzed by flow cytometry at the single-cell level. Combinations of several proteins (GSK3AB, HSBP1 or RS6) and immune cells (Th17, Th1 non-classic, CD8, CD8 Treg, CD56 neg, and B memory) were part of the paths explaining the clinical phenotype. The advantage of the path identified from the Boolean simulations is that it connects information about these known biological pathways with the layers at higher scales (retina damage and disability). Overall, the identified paths provide a means to connect the molecular aspects of MS with the overall phenotype.

Causal relationship between immune cells and neurodegenerative diseases: a two-sample Mendelian randomisation study

Background

There is increasing evidence that the types of immune cells are associated with various neurodegenerative diseases. However, it is currently unclear whether these associations reflect causal relationships.

Objective

To elucidate the causal relationship between immune cells and neurodegenerative diseases, we conducted a two-sample Mendelian randomization (MR) analysis.

Materials and methods

The exposure and outcome GWAS data used in this study were obtained from an open-access database (https://gwas.mrcieu.ac.uk/), the study employed two-sample MR analysis to assess the causal relationship between 731 immune cell features and four neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS). All immune cell data was obtained from Multiple MR methods were used to minimize bias and obtain reliable estimates of the causal relationship between the variables of interest and the outcomes. Instrumental variable selection criteria were restricted to ensure the accuracy and effectiveness of the causal relationship between species of immune cells and the risk of these neurodegenerative diseases.

Results

The study identified potential causal relationships between various immune cells and different neurodegenerative diseases. Specifically, we found that 8 different types of immune cells have potential causal relationships with AD, 1 type of immune cells has potential causal relationships with PD, 6 different types of immune cells have potential causal relationships with ALS, and 6 different types of immune cells have potential causal relationships with MS.

Conclusion

Our study, through genetic means, demonstrates close causal associations between the specific types of immune cells and AD, PD, ALS and MS, providing useful guidance for future clinical researches.

Mitochondrial and metabolic dysfunction of peripheral immune cells in multiple sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disorder characterized by the infiltration of inflammatory cells and demyelination of nerves. Mitochondrial dysfunction has been implicated in the pathogenesis of MS, as studies have shown abnormalities in mitochondrial activities, metabolism, mitochondrial DNA (mtDNA) levels, and mitochondrial morphology in immune cells of individuals with MS. The presence of mitochondrial dysfunctions in immune cells contributes to immunological dysregulation and neurodegeneration in MS. This review provided a comprehensive overview of mitochondrial dysfunction in immune cells associated with MS, focusing on the potential consequences of mitochondrial metabolic reprogramming on immune function. Current challenges and future directions in the field of immune-metabolic MS and its potential as a therapeutic target were also discussed.

Increased regulatory activity of intestinal innate lymphoid cells type 3 (ILC3) prevents experimental autoimmune encephalomyelitis severity

Experimental autoimmune encephalomyelitis (EAE) induced in inbred rodents, i.e., genetically identical animals kept under identical environmental conditions, shows variable clinical outcomes. We investigated such variations of EAE in Dark Agouti rats immunized with spinal cord homogenate and identified four groups: lethal, severe, moderate, and mild, at day 28 post immunization. Higher numbers of CD4+ T cells, helper T cells type 1 (Th1) and 17 (Th17) in particular, were detected in the spinal cord of the severe group in comparison with the moderate group. In addition, increased proportion of Th1 and Th17 cells, and heightened levels of interferon (IFN)-γ and interleukin (IL)-6 were detected in the small intestine lamina propria of the severe group. A selective agonist of free fatty acid receptor type 2 (Ffar2) applied orally in the inductive phase of EAE shifted the distribution of the disease outcomes towards milder forms. This effect was paralleled with potentiation of intestinal innate lymphoid cells type 3 (ILC3) regulatory properties, and diminished Th1 and Th17 cell response in the lymph nodes draining the site of immunization. Our results suggest that different clinical outcomes in DA rats are under determinative influence of intestinal ILC3 activity during the inductive phase of EAE.

Immunoswitch Nanomodulators Enable Active Targeting and Selective Proliferation of Regulatory T Cells for Multiple Sclerosis Therapy

Interleukin-2 (IL-2) used in multiple sclerosis (MS) therapy modulates the balance between regulatory T (Treg) cells and effector T (Teff) cells. However, the off-target activation of Teff cells by IL-2 limits its clinical application. Therefore, a rapidly prepared immunoswitch nanomodulator termed aT-IL2C NPs was developed, which specifically recognized Treg cells with high TIGIT expression thanks to the presence of an anti-TIGIT and an IL-2/JES6-1 complex (IL2C) being delivered to Treg cells but not to Teff cells with low TIGIT expression. Then, IL2C released IL-2 due to the specific expression of the high-affinity IL-2 receptor on Treg cells, thus enabling the active targeting and selective proliferation of Treg cells. Moreover, the anti-TIGIT of aT-IL2C NPs selectively inhibited the proliferation of Teff cells while leaving the proliferation of Treg cells unaffected. In addition, since the IL-2 receptor on Teff cells had medium-affinity, the IL2C hardly released IL-2 to Teff cells, thus enabling the inhibition of Teff cell proliferation. The treatment of experimental autoimmune encephalomyelitis (EAE) mice with aT-IL2C NPs ameliorated the severity of the EAE and restored white matter integrity. Collectively, this work described a potential promising agent for effective MS therapy.

Astragalus polysaccharides promote neural stem cells-derived oligodendrogenesis through attenuating CD8+T cell infiltration in experimental autoimmune encephalomyelitis

Endogenous neural stem cells (NSCs) have the potential to generate remyelinating oligodendrocytes, which play an important role in multiple sclerosis (MS). However, the differentiation of NSCs into oligodendrocytes is insufficient, which is considered a major cause of remyelination failure. Our previous work reported that Astragalus polysaccharides (APS) had a neuroprotective effect on experimental autoimmune encephalomyelitis (EAE) mice. However, it remains unclear whether APS regulate NSCs differentiation in EAE mice. In this study, our data illustrated that APS administration could promote NSCs in the subventricular zone (SVZ) to differentiate into oligodendrocytes. Furthermore, we found that APS significantly improved neuroinflammation and inhibited CD8+T cell infiltration into SVZ of EAE mice. We also found that MOG35-55-specific CD8+T cells suppressed NSCs differentiation into oligodendrocytes by secreting IFN-γ, and APS facilitated the differentiation of NSCs into oligodendrocytes which was related to decreased IFN-γ secretion. In addition, APS treatment did not show a better effect on the NSCs-derived oligodendrogenesis after CD8+T cell depletion. This present study demonstrated that APS alleviated neuroinflammation and CD8+T cell infiltration into SVZ to induce oligodendroglial differentiation, and thus exerted neuroprotective effect. Our findings revealed that reducing the infiltration of CD8+T cells might contribute to enhancing NSCs-derived neurogenesis. And APS might be a promising drug candidate to treat MS.

Neutrophil extracellular traps in central nervous system (CNS) diseases

Excessive induction of inflammatory and immune responses is widely considered as one of vital factors contributing to the pathogenesis and progression of central nervous system (CNS) diseases. Neutrophils are well-studied members of inflammatory and immune cell family, contributing to the innate and adaptive immunity. Neutrophil-released neutrophil extracellular traps (NETs) play an important role in the regulation of various kinds of diseases, including CNS diseases. In this review, current knowledge on the biological features of NETs will be introduced. In addition, the role of NETs in several popular and well-studied CNS diseases including cerebral stroke, Alzheimer's disease, multiple sclerosis, amyotrophic lateral sclerosis (ALS), and neurological cancers will be described and discussed through the reviewing of previous related studies.

Game of microbes: the battle within - gut microbiota and multiple sclerosis

Multiple sclerosis (MS) is a chronic and progressive autoimmune disease of the central nervous system (CNS), with both genetic and environmental factors contributing to the pathobiology of the disease. While human leukocyte antigen (HLA) genes have emerged as the strongest genetic factor, consensus on environmental risk factors are lacking. Recently, trillions of microbes residing in our gut (microbiome) have emerged as a potential environmental factor linked with the pathobiology of MS as PwMS show gut microbial dysbiosis (altered gut microbiome). Thus, there has been a strong emphasis on understanding the factors (host and environmental) regulating the composition of the gut microbiota and the mechanism(s) through which gut microbes contribute to MS disease, especially through immune system modulation. A better understanding of these interactions will help harness the enormous potential of the gut microbiota as a therapeutic approach to treating MS.

Association Between Immune-Related Disease and Allergic Rhinitis: A Two-Sample Mendelian Randomization Study

BACKGROUND

Immune-related diseases can interact with each other, and growing evidence suggests that these diseases are associated with allergic rhinitis (AR). However, it is unclear whether previously observed associations reflect causal relationships.

OBJECTIVE

This study estimated the genetic association between various immune-related diseases and AR using two-sample Mendelian randomization (MR).

METHODS

Eight immune-related diseases were selected as exposure factors, and AR was selected as the outcome. The 8 immune-related disease categories included atopic dermatitis (AD), Graves' disease (GD), asthma, Crohn's disease (CD), multiple sclerosis (MS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and ulcerative colitis (UC). Data from GWAS (Genome-Wide Association Studies) were selected to construct instrumental variables (IVs) for each disease, and multiple single-nucleotide polymorphisms (SNPs) were selected as IVs. Corresponding data were retrieved according to the selected SNPs, and all data were summarized and analyzed.

RESULTS

A total of 416 SNPs were screened as IVs, and the results of IVW support a causal relationship between AR risk and AD (OR: 1.026, 95% CI: 1.014-1.038, P = 9.59 × 10-6), asthma (OR: 1.057, 95% CI: 1.029-1.086, P = .0001), and CD (OR: 1.006, 95% CI: 1.002-1.011, P = .0085). Furthermore, GD (OR: 0.995, 95% CI: 0.991-0.999, P = .0213) and SLE (OR: 0.997, 95% CI: 0.995-1.000, P = .025) may be protective factors.

CONCLUSION

This MR study found that AD, asthma and CD increase the risk of AR in populations of European ancestry, GD and SLE may be protective factors. These results suggest that confounding factors may have influenced associations previously reported in observational studies.

ROS-Scavenging Lignin-Based Tolerogenic Nanoparticle Vaccine for Treatment of Multiple Sclerosis

Multiple sclerosis (MS) is a demyelinating autoimmune disease, in which the immune system attacks myelin. Although systemic immunosuppressive agents have been used to treat MS, long-term treatment with these drugs causes undesirable side effects such as altered glucose metabolism, insomnia, and hypertension. Herein, we propose a tolerogenic therapeutic vaccine to treat MS based on lignin nanoparticles (LNP) with intrinsic reactive oxygen species (ROS)-scavenging capacity derived from their phenolic moieties. The LNP loaded with autoantigens of MS allowed for inducing tolerogenic DCs with low-level expression of costimulatory molecules while presenting antigenic peptides. Intravenous injection of an LNP-based tolerogenic vaccine into an experimental autoimmune encephalomyelitis (EAE) model led to durable antigen-specific immune tolerance via inducing regulatory T cells (Tregs). Autoreactive T helper type 1 cells, T helper type 17 cells, and inflammatory antigen presentation cells (APCs) were suppressed in the central nervous system (CNS), ameliorating ongoing MS in early and late disease states. Additionally, the incorporation of dexamethasone into an LNP-based tolerogenic nanovaccine could further improve the recovery of EAE mice in the severe chronic stage. As lignin is the most abundant biomass and waste byproduct in the pulping industry, a lignin-based tolerogenic vaccine could be a novel, cost-effective, high-value vaccine platform with potent therapeutic efficiency in treating autoimmune diseases.

Potential of Nano-Engineered Stem Cells in the Treatment of Multiple Sclerosis: A Comprehensive Review

Multiple sclerosis (MS) is a chronic and degrading autoimmune disorder mainly targeting the central nervous system, leading to progressive neurodegeneration, demyelination, and axonal damage. Current treatment options for MS are limited in efficacy, generally linked to adverse side effects, and do not offer a cure. Stem cell therapies have emerged as a promising therapeutic strategy for MS, potentially promoting remyelination, exerting immunomodulatory effects and protecting against neurodegeneration. Therefore, this review article focussed on the potential of nano-engineering in stem cells as a therapeutic approach for MS, focusing on the synergistic effects of combining stem cell biology with nanotechnology to stimulate the proliferation of oligodendrocytes (OLs) from neural stem cells and OL precursor cells, by manipulating neural signalling pathways-PDGF, BMP, Wnt, Notch and their essential genes such as Sox, bHLH, Nkx. Here we discuss the pathophysiology of MS, the use of various types of stem cells in MS treatment and their mechanisms of action. In the context of nanotechnology, we present an overview of its applications in the medical and research field and discuss different methods and materials used to nano-engineer stem cells, including surface modification, biomaterials and scaffolds, and nanoparticle-based delivery systems. We further elaborate on nano-engineered stem cell techniques, such as nano script, nano-exosome hybrid, nano-topography and their potentials in MS. The article also highlights enhanced homing, engraftment, and survival of nano-engineered stem cells, targeted and controlled release of therapeutic agents, and immunomodulatory and tissue repair effects with their challenges and limitations. This visual illustration depicts the process of utilizing nano-engineering in stem cells and exosomes for the purpose of delivering more accurate and improved treatments for Multiple Sclerosis (MS). This approach targets specifically the creation of oligodendrocytes, the breakdown of which is the primary pathological factor in MS.