Should mast cells be considered therapeutic targets in multiple sclerosis?

Mast cells are immune cells of the myeloid lineage that are found throughout the body,including the central nervous system.They perform many functions associated with innate and specific immunity,angiogenesis,and vascular homeostasis.Moreover,they have been implicated in a series of pathologies(e.g.,hypersensitivity reactions,tumors,and inflammatory disorders).In this review,we propose that this cell could be a relevant therapeutic target in multiple sclerosis,which is a central nervous system degenerative disease.To support this proposition,we describe the general biological properties of mast cells,their contribution to innate and specific immunity,and the participation of mast cells in the various stages of multiple sclerosis and experimental autoimmune encephalomyelitis development.The final part of this review is dedicated to an overview of the available mast cells immunomodulatory drugs and their activity on multiple sclerosis and experimental autoimmune encephalomyelitis,including our own experience related to the effect of ketotifen fumarate on experimental autoimmune encephalomyelitis evolution.

Mast cells and multiple sclerosis in females and males

Mast cells were observed in autopsies from 11 females and 8 males. We confirm earlier observations that mast cells are more frequent in close vicinity to MS-plaques. In these plaque-border zone areas, defined as the area within 1 mm distance of the actual plaques, the average number of mast cells was 2.34/mm2 in males and 4.77/mm2 in females, which in average is appr. 10 times more than earlier observed in MS. The difference in number of mast cells between females and males is significant (p < 0.005) and is of interest since females are more inclined to developing MS than males. Mast cells were rare in areas without visible plaques. The mast cells were preferably located close to capillaries and venules. A mechanism for the probable role of mast cells, based on diet-factors and mast cell mediators in the pathogenesis of MS is discussed.

Mast Cells:The Key to Multiple Sclerosis?

Mast cells are present in high numbers in the border-zones of the multiple sclerosis-plaques. They are located in small clusters along capillaries and venules, and they are more abundant in females than in men. Mast cells can be stimulated to release specific mediators such as histamine, resulting in oedema formation, as well as proteases that may cause demyelination, by several different activation mechanisms. We hypothesize that a putative mast cell activation may be induced by diet factor(s) as well as long lasting mental stress that may lead to the release of catestatin, as well as ACTH released from the pituitary gland. Given a natural flux of mast cell recovery and activation, a putative phenomenon of massive release of mediators and “silent” reload periods may explain the relapsing-remitting phases of multiple sclerosis.

Multiple Sclerosis:A Mast Cell Mediated Psycho-Somatic Disease?

This paper reviews evidence that the presence of mast cells in specific sites of central nervous system, suggesting inflammatory processes, may explain all the symptoms observed in multiple sclerosis. This hypothesis would be relatively easy to test.

Exploring the mechanism of Yishen Daluo decoction in the treatment of multiple sclerosis based on network pharmacology and in vitro experiments

Objective:To explore the mechanism and related active components of Yishen Daluo decoction(YSDLD)in treating multiple sclerosis(MS).Methods:Targets of YSDLD were collected through the TCMSP,Chemistry,and TCMID databases.The MS targets were collected through OMIM,DrugBank,Gencards,TTD,and Pharmgkb databases.We built“componentetarget”network diagrams and proteineprotein interaction(PPI)diagrams and performed topological analysis.The targets were subjected to GO and KEGG enrichment analysis.Molecular docking verification was conducted on selected targets and molecules.Finally,in vitro experiments were con-ducted.BV2 cells were induced by lipopolysaccharide for model establishment.CCK8 experiment was conducted to explore the effect of YSDLD and RT-qPCR technology was used to explore the expression of key targets.Results:There were 184 active components in YSDLD and 898 targets of its action.There were 940 MS targets,and 215 targets were shared by YSDLD and MS.According to the“componentetarget”diagram,the top five key components included quercetin,kaempferol,beta-sitosterol,stigmasterol,and nar-ingenin.IL-6,IL-1 b,TNF-α,AKT1,and VEGFA were the important targets identified by PPI network to-pology analysis.A total of 564 functions were identified by GO enrichment analysis(P<0.01),mainly involving inflammatory response,hypoxia response,plasma membrane,neuronal cell body,protein phosphatase binding,and cytokine activity.KEGG enrichment analysis enriched 98 pathways(P<.01).YSDLD at the concentration of 20 m g/mL had no effect on BV2 cells.RT-qPCR indicated that YSDLD at the concentrations of 15 m g/mL and 20 m g/mL alleviated LPS-induced inflammatory injury and lowered the content of inflammatory factors(P<0.05).Conclusion:In this paper,the network pharmacology and in vitro experiments were used to explore the potential mechanism of YSDLD in treating MS.The research provides a good basis for the development of YSDLD and drugs for MS in future.

The contribution of oligodendrocytes and oligodendrocyte progenitor cells to central nervous system repair in multiple sclerosis： perspectives for remyelination therapeutic strategies

Oligodencrocytes（OLs） are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis（MS）, there is an imbalance between demyelination and remyelination processes, the last one performed by oligodendrocyte progenitor cells（OPCs） and OLs, resulting into a permanent demyelination, axonal damage and neuronal loss. In MS lesions, astrocytes and microglias play an important part in permeabilization of blood-brain barrier and initiation of OPCs proliferation. Migration and differentiation of OPCs are influenced by various factors and the process is finalized by insufficient acummulation of OLs into the MS lesion. In relation to all these processes, the author will discuss the potential targets for remyelination strategies.

Multiple sclerosis and the role of immune cells

Multiple sclerosis(MS) is a complex disease with many different immune cells involved in its pathogenesis, and in particular T cells as the most recognized cell type. Recently, the innate immune system has also been researched for its effect on the disease. Hence, cells of the immune system play vital roles in either ameliorating or exacerbating the disease. The genetic and environmental factors, as well as the etiology and pathogenesis are of utmost importance for the development of MS. An insight into the roles play by T cells, B cells, natural killer cells, and dendritic cells in MS and the animal model experimental autoimmune encephalomyelitis, will be presented. Understanding the mechanisms of action for current therapeutic modalities should help developing new therapeutic tools to treat this disease and other autoimmune diseases.

Optical coherence tomography and T cell gene expression analysis in patients with benign multiple sclerosis

Benign multiple sclerosis is a retrospective diagnosis based primarily on a lack of motor symptom progression. Recent findings that suggest patients with benign multiple sclerosis experience non-motor symptoms highlight the need for a more prospective means to diagnose benign multiple sclerosis early in order to help direct patient care. In this study, we present optical coherence tomography and T cell neurotrophin gene analysis findings in a small number of patients with benign multiple sclerosis. Our results demonstrated that retinal nerve fiber layer was mildly thinned, and T cells had a distinct gene expression profile that included upregulation of interleukin 10 and leukemia inhibitory factor, downregulation of interleukin 6 and neurotensin high affinity receptor 1（a novel neurotrophin receptor）. These findings add evidence for further investigation into optical coherence tomography and m RNA profiling in larger cohorts as a potential means to diagnose benign multiple sclerosis in a more prospective manner.

Transient Receptor Potential Melastatin 3 and Intracellular Calcium in Natural Killer Cells in Multiple Sclerosis

Background: Natural killer (NK) cell phenotypes have reported to be implicated in the pathomechanism of Multiple Sclerosis (MS). Several investigators have observed reduced peripheral numbers, reduced cytotoxic activity, and altered CD56Dim and CD56Bright NK cell phenotypes. This current project, for the first time, investigates the NK cell cytotoxicity, calcium mobilisation and transient receptor potential melastatin 3 (TRPM3) surface expression. Methods: NK cell cytotoxic activity and calcium signaling were examined in CD56Dim and CD56Bright NK cells before and after stimulation using Ionomycin, Pregnenolone sulphate, 2-Aminoethoxydiphenyl borate and Thapsigargin. Purified NK cells were labelled with antibodies to determine TRPM3, CD69 and CD107a surface expression using flow cytometry. Results: Twenty-two MS patients and 22 healthy controls were recruited for this project. Twelve of the 22 previously received Alemtuzumab (Lemtrada&reg;) and the remaining ten reported nil medication. We report TRPM3 was significantly increased in untreated MS patients compared with healthy controls and treated MS patients (p-value 0.034). There was a significant decrease in CD69 surface expression on CD56Dim NK cell phenotype for untreated MS patients (p-value 0.031) and treated MS patients (p-value 0.036). We report altered calcium mobilisation in CD56Bright NK cells and to a lesser extent CD56Dim NK cells between healthy controls, treated and untreated MS patients. Conclusion: This investigation suggests variations in TRPM3 expression and calcium mobilisation of NK cells may be implicated in the pathogenesis of MS. Further investigation is required to determine the mechanism by which alemtuzumab alters calcium signaling in NK cells.

Role of nuclear factor κB in multiple sclerosis and experimental autoimmune encephalomyelitis

The transcription factor nuclear factor κB（NF-κB） plays major roles in inflammatory diseases through regulation of inflammation and cell viability.Multiple sclerosis（MS） is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system（CNS）.It has been shown that NF-κB is activated in multiple cell types in the CNS of MS patients,including T cells,microglia/macrophages,astrocytes,oligodendrocytes,and neurons.Interestingly,data from animal model studies,particularly studies of experimental autoimmune encephalomyelitis,have suggested that NF-κB activation in these individual cell types has distinct effects on the development of MS.In this review,we will cover the current literature on NF-κB and the evidence for its role in the development of MS and its animal model experimental autoimmune encephalomyelitis.

Chemotactic signaling and beyond: link between interleukin-16 and axonal degeneration in multiple sclerosis

Multiple sclerosis（MS）is a progressive inflammatory,and chronic demyelinating,neurodegenerative disease of central nervous system（CNS）.Autoimmune responses to myelin and other CNS antigens mediated by cluster of differentiation 4（CD4＋）T cells are critical for initiation and progression of disease.Migration of autoimmune T cells from the peripheral lymph organs into CNS parenchyma leads to inflammation,demyelination and damage of axonal cytoskeleton, which manifest in decreased impulse conduction velocity of motor and sensory nerves. Myelin and axonal pathology causes motor, sensory and autonomic nerve dysfunction, including optic nerve damage leading to double or distorted vision; paresis and paralysis of extremities, painful sensations, and bladder sphincter dysfunction, manifested as bladder incontinence. Gray matter pa- thology in cortical and subcortical regions, including cerebellum and hippocampus underlies cognitive and behavioral dysfunction consisting of memory deficits, depression, and ataxic gait and tremor.

The role of Epstein-Barr virus in multiple sclerosis:from molecular pathophysiology to in vivo imaging

Multiple sclerosis(MS) is a disease of the central nervous system characterized by inflammation, demyelination, and neuronal damage. Environmental and genetic factors are associated with the risk of developing MS, but the exact cause still remains unidentified. Epstein-Barr virus(EBV), vitamin D, and smoking are among the most well-established environmental risk factors in MS. Infectious mononucleosis, which is caused by delayed primary EBV infection, increases the risk of developing MS. EBV may also contribute to MS pathogenesis indirectly by activating silent human endogenous retrovirus-W. The emerging B-cell depleting therapies, particularly anti-CD20 agents such as rituximab, ocrelizumab, as well as the fully human ofatumumab, have shown promising clinical and magnetic resonance imaging benefit. One potential effect of these therapies is the depletion of memory B-cells, the primary reservoir site where EBV latency occurs. In addition, EBV potentially interacts with both genetic and other environmental factors to increase susceptibility and disease severity of MS. This review examines the role of EBV in MS pathophysiology and summarizes the recent clinical and radiological findings, with a focus on B-cells and in vivo imaging. Addressing the potential link between EBV and MS allows the better understanding of MS pathogenesis and helps to identify additional disease biomarkers that may be responsive to B-cell depleting intervention.

Is there a window of opportunity for the therapeutic use of vitamin D in multiple sclerosis?

Multiple sclerosis is an autoimmune treatable but not curable disease.There are a multiplicity of medications for multiple sclerosis therapy,including a class entitled disease-modifying drugs that are mainly indicated to reduce the number and severity of disease relapses.Not all patients respond well to these therapies,and minor to severe adverse effects have been reported.Vitamin D,called sunshine vitamin,is being studied as a possible light at the end of the tunnel.In this review,we recapitulated the similar immunopathogenesis of multiple sclerosis and experimental autoimmune encephalomyelitis,the immunomodulatory and neuroprotective potential of vitamin D and the state-of-art concerning its supplementation to multiple sclerosis patients.Finally,based on our and other groups’experimental findings,we analyzed the need to consider the relevance of the route and the different time-point administration aspects for a more rational indication of this vitamin to multiple sclerosis patients.

TREM-2 Drives Development of Multiple Sclerosis by Promoting Pathogenic Th17 Polarization

Multiple sclerosis(MS)is a neuroinflammatory demyelinating disease,mediated by pathogenic T helper 17(Th17)cells.However,the therapeutic effect is accompa-nied by the fluctuation of the proportion and function of Th17 cells,which prompted us to find the key regulator of Th17 differentiation in MS.Here,we demonstrated that the triggering receptor expressed on myeloid cells 2(TREM-2),a modulator of pattern recognition receptors on innate immune cells,was highly expressed on pathogenic CD4-positive T lymphocyte(CD4^(+)T)cells in both patients with MS and experimental autoimmune encephalomyelitis(EAE)mouse models.Conditional knockout of Trem-2 in CD4^(+)T cells significantly alleviated the disease activity and reduced Th17 cell infiltration,activation,differentiation,and inflammatory cytokine production and secretion in EAE mice.Furthermore,with Trem-2 knockout in vivo experiments and in vitro inhibitor assays,the TREM-2/zeta-chain associated protein kinase 70(ZAP70)/signal transducer and activator of transcription 3(STAT3)signal axis was essential for Th17 activation and differentiation in EAE progression.In conclusion,TREM-2 is a key regulator of pathogenic Th17 in EAE mice,and this sheds new light on the potential of this therapeutic target for MS.

A global online study of haematopoietic stem cell transplantation in multiple sclerosis and other neurodegenerative disorders

Background:The objective of this study was to understand the uptake of hemopoietic stem cell transplantation(HSCT)in neuroimmunological disorders like multiple sclerosis(MS).Method:An independent University affiliated research organization conducted a global online survey of people having had HSCT,examining demographics,treatment protocol,and effectiveness.Results:Of 271 participants,useful data were available in 223;women aged 35–54 accounted for 73.5%.Most had a household income greater than US$50,000,and the majority of participants were from Australia and the United States.Nearly 94.6%of people suffer from MS.Most had their treatment in Russia(38.7%)and 78.1%had nonmyeloablative transplants.Nearly half of the participants spent between US$50,000 to US$74,999.There were 54.5%of neurologists who did not support their patients having HSCT.Around 85.5%of participants believed HSCT helped them manage their disease from weeks to years after transplantation,and treatment was recommended by 9.5%of participants.The average reduction in Expanded Disability Status Score after transplantation was 1.2(95%CI:0.97–1.41;N=197;p<0.01;t:10.7,df:196).Conclusion:Participants were supportive of HSCT despite the costs and would recommend it to others.The data suggest some benefit in minimizing disability in MS and provides justification for large randomized controlled trials.

Glia Connect Inflammation and Neurodegeneration in Multiple Sclerosis

Multiple sclerosis(MS)is regarded as a chronic inflammatory disease that leads to demyelination and eventually to neurodegeneration.Activation of innate immune cells and other inflammatory cells in the brain and spinal cord of people with MS has been well described.However,with the innovation of technology in glial cell research,we have a deep understanding of the mechanisms of glial cells connecting inflammation and neurodegeneration in MS.In this review,we focus on the role of glial cells,including microglia,astrocytes,and oligodendrocytes,in the pathogenesis of MS.We mainly focus on the connection between glial cells and immune cells in the process of axonal damage and demyelinating neuron loss.

Treatment of multiple sclerosis by transplantation of neural stem cells derived from induced pluripotent stem cells

Multiple sclerosis(MS) is an autoimmune disease of the central nervous system(CNS), with focal T lymphocytic infiltration and damage of myelin and axons. The underlying mechanism of pathogenesis remains unclear and there are currently no effective treatments. The development of neural stem cell(NSC) transplantation provides a promising strategy to treat neurodegenerative disease. However, the limited availability of NSCs prevents their application in neural disease therapy. In this study, we generated NSCs from induced pluripotent stem cells(iPSCs) and transplanted these cells into mice with experimental autoimmune encephalomyelitis(EAE), a model of MS. The results showed that transplantation of iPSC-derived NSCs dramatically reduced T cell infiltration and ameliorated white matter damage in the treated EAE mice. Correspondingly, the disease symptom score was greatly decreased, and motor ability was dramatically rescued in the iPSC-NSC-treated EAE mice, indicating the effectiveness of using iPSC-NSCs to treat MS. Our study provides pre-clinical evidence to support the feasibility of treating MS by transplantation of iPSC-derived NSCs.

Clinical outcomes after autologous haematopoietic stem cell transplantation in patients with progressive multiple sclerosis

Background Multiple sclerosis （MS） is a continuously disabling disease and it is unresponsive to high dose steroid and immunomodulation with disease progression. The autologous haematopoietic stem cell transplantation （ASCT） has been introduced in the treatment of refractory forms of multiple sclerosis. In this study, the clinical outcomes followed by ASCT were evaluated for patients with progressive MS. Methods Twenty-two patients with secondary progressive MS were treated with ASCT. Peripheral blood stem cells were obtained by leukapheresis after mobilization with granulocyte colony stimulating factor. Etoposide, melphalan, carmustin and cytosine arabinoside were administered as conditioning regimen. Outcomes were evaluated by the expanded disability status scale and progression free survival. No maintenance treatment was administered during a median follow-up of 39 months （range, 6 to 59 months）. Results No death occurred following the treatment. The overall confirmed progression free survival rate was 77% up to 59 months after transplantation which was significantly higher compared with pre-transplantation （P=0.000）. Thirteen patients （59%） had remarkable improvement in neurological manifestations, four （18%） stabilized their disability status and five （23%） showed clinical recurrence of active symptoms. Conclusions ASCT as a therapy is safe and available. It can improve or stabilize neurological manifestations in most patients with progressive MS following failure of conventional therapy.

黄芪甲苷对实验性自身免疫性脑脊髓炎小鼠T细胞免疫调节的影响

背景:多发性硬化初始阶段,中枢免疫细胞激活并释放大量炎症因子,引起白质脱髓鞘甚至累及灰质神经元。CD4^(+)T细胞不同亚群之间的分化平衡在实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)的病程进展中发挥着重要作用。课题组前期研究结果表明黄芪内有效成分黄芪甲苷能够调节EAE小鼠体内免疫反应,其是否对T细胞亚群分化具有调节作用尚未明确。目的:探究黄芪甲苷对EAE小鼠治疗效果及其对T细胞的免疫调控机制。方法:将C57BL/6雌性小鼠分为正常对照组、EAE疾病模型组和黄芪甲苷治疗组,每组8只,后2组使用髓鞘少突胶质细胞糖蛋白35-55(MOG35-55)制备EAE模型,免疫后第10-28天,黄芪甲苷治疗组以40 mg/(kg·d)灌胃给药。免疫当天至第28天,记录各组小鼠的体质量及临床评分;免疫后第28天取小鼠脊髓制成冰冻切片行苏木精-伊红染色、固蓝染色观察脊髓病理改变,流式细胞术检测脾脏T细胞亚群百分比,Western blot法检测脊髓组织中γ干扰素、白细胞介素17、白细胞介素6的蛋白表达,ELISA检测脾细胞上清液中γ干扰素、白细胞介素17、白细胞介素6、白细胞介素4水平。结果与结论:(1)与EAE疾病模型组相比,黄芪甲苷治疗能够减少EAE小鼠体质量丢失(P<0.05),缓解临床症状(P<0.05),减轻脊髓炎症细胞浸润及髓鞘脱失病理改变(分别为P<0.01和P<0.05);(2)与EAE疾病模型组相比,黄芪甲苷治疗可抑制表达γ干扰素和白细胞介素17的CD4^(+)T细胞亚群比例(分别为P<0.001和P<0.001),上调表达白细胞介素10和转化生长因子β的CD4^(+)T细胞亚群百分比(分别为P<0.001和P<0.01);(3)黄芪甲苷可下调脊髓和脾脏中γ干扰素(分别为P<0.05和P<0.01)、白细胞介素17(分别为P<0.05和P<0.05)、白细胞介素6(分别为P<0.05和P<0.05)的表达,上调脾脏中抑炎因子白细胞介素4的表达(P<0.01);(4)结果说明,黄芪甲苷可以减轻EAE小鼠的临床症状,其机制与调节脾脏免疫细胞亚群进而抑制炎症细胞向中枢浸润、减少髓鞘脱失有关。

Cytometric profiling in various clinical forms of multiple sclerosis with respect to CD21^(+), CD32^(+), and CD35^(+) B and T cells

Background:We aimed to evaluate the frequency of various types of B and T cells expressing CD21,CD32,and CD35 in multiple sclerosis(MS)clinical courses.Methods:Peripheral blood mononuclear cell from 30 MS patients(17 relapsing remitting[RRMS],six secondary progressive[SPMS],and seven primary progressive MS[PPMS])and 18 healthy subjects were analyzed.All patients were in acute attack.Healthy controls were matched for age and gender ratio.The frequencies of various subsets of B and T cells were determined using flow cytometry.Results:The frequency of CD4^(+)T cells was lower in MS patients compared to control subjects(41.14±9.45%vs.46.88±6.98%,respectively,P<0.05).The CD32^(+)fraction of CD4^(+)T cells and the CD21^(+)fraction of CD8^(+)T cells were higher in MS patients(2.85±3.72%vs.1.06±0.62%for CD32^(+)CD4^(+)T cells,2.71±1.86%vs.1.16±0.99%for CD21^(+)CD8^(+)T cells in MS patients and control subjects,respectively,P<0.05).After dividing subjects by type of MS course,higher values of these two T cell subsets were found in SPMS patients compared to control subjects(P<0.05).Further,RRMS patients had lower levels of CD32^(+)CD4^(+)T cells than SPMS patients and also they had lower levels of CD32^(+)CD8^(+)T cells than PPMS patients(P<0.05).However,neither the expression of CD35 on T cells nor the various B cell subsets were statistically different between the compared groups.Conclusions:Our findings demonstrate that T cell subsets expressing CD21 and CD32 may differ with respect to the presence or clinical forms of MS disease.By contrast,CD35^(+)T cells and different subsets of B cells are not altered in various MS clinical courses.