Act1介导的IL-17信号通路与自身免疫性脑脊髓炎关系的研究进展

多发性硬化(multiple sclerosis,MS)是以中枢神经系统(central nervous system,CNS)慢性炎症性脱髓鞘为主要特征的自身免疫性疾病。实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)在发病特点和病理学特征上与人类的MS表现非常相似,是研究MS发病机制及治疗的理想的动物模型。辅助性T细胞17(T helper cell 17,Th17)细胞是CD4~+T细胞的一个重要亚群,主要分泌IL-17(interleukin-17)细胞因子,在EAE的发病过程中具有重要作用。NF-κB激活剂1(NF-κB activator 1,Act1)是SEFIR(similar expression to fibroblast growth factor genes/IL-17R)蛋白家族的一员,是IL-17信号通路的连接蛋白。在IL-17的刺激下,Act1通过SEFIR-SEFIR相互作用招募到IL-17受体(IL-17 receptor,IL-17R)上,以调节下游信号通路。对Act1介导的IL-17信号与自身免疫性疾病的关系做一综述,以期为EAE的发病机制研究和治疗提供重要的理论基础和分子靶标。     

SD大鼠缓解-复发型实验性变态反应性脑脊髓炎模型的建立

目的:建立大鼠缓解-复发型实验性变态反应性脑脊髓炎(EAE)模型,进行病理学研究,为多发性硬化(MS)的研究提供据.方法:采用大鼠脊髓和弗氏完全佐剂混合乳剂一次性注入 SD 大鼠双足垫和尾部,1周后半剂量注射进行一次加强,诱导大鼠发生 EAE;观察发病情况,HE 染色观察病理变化,监牢兰染色观察脱髓鞘情况.结果:空白对照组大鼠均未出现症状,HE 染色小脑及脊髓无炎性细胞浸润,监牢兰染色未见髓鞘脱失;模型组临床症状发生率为90%以上,HE 染色可见小脑白质及脊髓血管周围有大量炎性细胞浸润,监牢兰染色发现有大片髓鞘脱落.结论:用 SD 大鼠脊髓髓鞘蛋白和弗氏完全佐剂混合乳剂可诱导同种 SD 大鼠发生缓解-复发型 EAE.     

复发缓解型实验性变态反应性脑脊髓炎动物模型的建立

目的:建立复发缓解型实验性变态反应性脑脊髓炎(EAE)动物模型,进行病理学研究,为多发性硬化(MS)的发病机制研究及治疗药物研发提供合适的动物模型。方法:选择不同品系动物(昆明种、BALB/c和C57BL/6小鼠,SD大鼠),采用各自品系来源的脊髓和弗氏完全佐剂混合乳剂一次性注入动物双足垫,1周后半剂量注射进行一次加强,诱导EAE;观察发病情况,HE染色观察病理变化,监牢兰染色观察脱髓鞘情况。结果:昆明种、BALB/c和C57BL/6小鼠均无明显症状,HE染色小脑的脊髓无炎性细胞浸润;SD大鼠对照组正常,模型组临床症状发生率为90%以上,HE染色可见小脑白质及脊髓血管周围有大量的炎性细胞浸润,监牢兰染色可见大片髓鞘脱落。结论:EAE模型在昆明种、BALB/c及C57BL/6小鼠中用脊髓匀浆不易于诱导,而用SD大鼠脊髓髓鞘蛋白和弗氏完全佐剂混合乳剂可高效率诱导出同种SD大鼠的复发缓解型EAE。     

多发性硬化实验动物模型研究进展

实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)是多发性硬化的实验动物模型,经过近2个多世纪的发展,已可以在猴、大鼠、小鼠等动物制备EAE模型,在同一种品系动物采用不同免疫抗原制备的EAE模型在敏感性和临床特点具有多样性。本研究就EAE的发展史和目前不同品系实验动物、不同抗原制备EAE模型的特点做一述评,对未来EAE模型的发展前景进行探讨。     

多发性硬化疾病及模型小鼠中疾病相关细胞因子和转录因子研究进展

多发性硬化症（multiple sclerosis,MS）是一种原发于中枢神经系统的炎症性脱髓鞘疾病。实验性自身免疫性脑脊髓炎（experimental autoimmune encephalomyelitis,EAE）与MS有相似的临床症状和病理特征,是被广泛应用于人类疾病研究的动物模型。MS确切的发病机制尚不清楚,但普遍认为是在易感基因的基础上,受环境因素触发,由CD4＋T细胞介导的中枢神经系统（centralnervous system,CNS）自身免疫性疾病。初始CD4＋T细胞在T细胞受体介导下活化,继而可分化为至少4个主要亚型,分别为TH1、TH2、TH17和iTreg细胞,参与不同类型的免疫应答。细胞因子和转录因子网络对CD4＋T细胞分化和效应细胞因子产物有重要意义。该文综述了各相关细胞因子和转录因子在CD4＋T细胞向不同亚型分化及MS/EAE发病过程中的相互作用和调控,揭示各因子在这些过程中的作用,有助于进一步研究和治疗MS。     

干扰素-τ治疗多发性硬化症的临床应用前景

作为从反刍动物体内发现的一种新型干扰素,干扰素-τ(IFN-τ)具有免疫调节、低细胞毒性等特点。实验性变应性脑脊髓炎(EAE)是多发性硬化症(MS)的动物模型。IFN-τ能够抑制实验性脑脊髓炎的发生、发展。本文简要综述了IFN-τ的结构、生物活性、低细胞毒性,以及它对EAE的治疗作用和机制。     

C57BL/6J小鼠实验性自身免疫性脑脊髓炎模型的建立及其病理特征

目的探讨C57BL/6J小鼠建立实验性自身免疫性脑脊髓炎（EAE）模型的可能性及其发病特点。方法使用PLP139-151抗原及其C57BL/6J小鼠自制脑脊髓匀浆（spinal cord homogenate,SCH）免疫C57BL/6J小鼠,使用完全福（氏）免疫佐剂为免疫佐剂,并在尾静脉注射百日咳杆菌,建立EAE模型,与经典的PLP139-151免疫的SJL/J小鼠EAE模型进行对比。结果PLP139-151免疫C57BL/6J小鼠仅有一只小鼠表现为尾部张力明显降低;自制SCH免疫C57BL/6J小鼠可见明显脱髓鞘改变。与PLP139-151免疫SJL/J小鼠组相比发病率较低（P〈0.05）,神经功能评分比较没有明显差异（P〉0.05）,但发病时间长于PLP139-151免疫SJL/J小鼠组（P〈0.05）。结论SCH免疫C57BL/6J小鼠的EAE动物模型,主要表现为急性单相病程,从临床表现和病理学特点来看符合人类MS的病理特点,值得在以后的研究中进一步研究探讨。     

脑多发性硬化的MRI诊断

目的:探讨脑内多发性硬化(MS)的核磁共振(MRI)诊断价值.方法:回顾性分析48例经临床确诊为MS患者的MRI表现及相关资料.48例均行MRI常规平扫,46例加做增强扫描.结果:(1)病灶多发,主要分布于侧脑室周围及额、颞、顶、枕叶皮层下白质区,部分累及胼胝体、小脑、脑干、丘脑、基底节及大脑皮质;双侧侧脑室旁可见“垂直脱髓鞘征”;(2)病灶主要以长和较长T2、略长和等T1信号为主;(3)增强扫描显示强化与不强化病灶同时存在,强化病灶呈点状、斑片及环形;少数急性起病病例病灶呈较均匀一致的强化.结论:MRI是临床诊断MS的敏感、直观、最有价值的检查手段.     

依达拉奉对大鼠实验性自身免疫性脑脊髓炎的保护作用

目的:研究依达拉奉对实验性自身免疫性脑脊髓炎(Experimental Autoimmune Encephalomyelitis,EAE)的影响。方法:72只健康成年雌性Wistar大鼠随机分为:正常对照组、EAE组、EAE+小剂量依达拉奉组、EAE+大剂量依达拉奉组(n=18)。正常对照组注射生理盐水,其它组采用自制完全抗原诱导EAE模型。EAE组建模后不做任何处理,EAE+小剂量依达拉奉组、EAE+大剂量依达拉奉组分别在建模后给予依达拉奉4mg/k·d、10mg/k·d。比较各组发病率并行神经功能评分,取脊髓组织行HE染色、iNOS、OPN免疫组织化学染色观察。结果:依达拉奉干预组大鼠较EAE组发病率、神经功能缺损评分均明显降低(P<0.05)。HE结果显示依达拉奉干预组较EAE组炎症反应减少,损伤程度减轻。依达拉奉组iNOS、OPN表达均明显小于EAE组(P<0.05)。大剂量依达拉奉iNOS、OPN表达均低于小剂量依达拉奉组(P<0.05)。结论:依达拉奉对EAE具有保护作用,可能与抑制小神经胶质细胞活化,减轻炎症反应,降低iNOS和OPN表达有关。     

Non-invasive measurement of brain damage in a primate model of multiple sclerosis

Early recognition of whether a product has potential as a new therapy for treating multiple sclerosis (MS) relies upon the quality of the animal models used in the preclinical trials. The promising effects of new treatments in rodent models of experimental autoimmune encephalomyelitis (EAE) have rarely been reproduced in patients suffering from MS. EAE in outbred marmoset monkeys, Callithrix jacchus, is a valid new model, and might provide an experimental link between EAE in rodent models and human MS. Using magnetic resonance imaging techniques similar to those used in patients suffering from MS pathological abnormalities in the brain, white matter of the animal can be visualized and quantified. Moreover, NMR spectroscopy, in combination with pattern recognition, offers an advanced uroscopic technique for the identification of biomarkers of inflammatory demyelination.     

Preliminary biological evaluations of new thalidomide analogues for multiple sclerosis application

The present work deals with the synthesis of a new series of thalidomide derivatives for therapeutic applications. These compounds were evaluated in vitro on a human endothelial cell line EA.hy926 for their antiproliferative potential and in vivo on an experimental animal multiple sclerosis model called EAE as angiogenesis inhibitors. The preliminary results obtained on EAE assays seem to validate that anti-angiogenesis compounds could be promising tools for the treatment of MS.     

VCAM-1-targeted magnetic resonance imaging reveals subclinical disease in a mouse model of multiple sclerosis

Diagnosis of multiple sclerosis (MS) currently requires lesion identification by gadolinium (Gd)-enhanced or T(2)-weighted magnetic resonance imaging (MRI). However, these methods only identify late-stage pathology associated with blood-brain barrier breakdown. There is a growing belief that more widespread, but currently undetectable, pathology is present in the MS brain. We have previously demonstrated that an anti-VCAM-1 antibody conjugated to microparticles of iron oxide (VCAM-MPIO) enables in vivo detection of VCAM-1 by MRI. Here, in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS, we have shown that presymptomatic lesions can be quantified using VCAM-MPIO when they are undetectable by Gd-enhancing MRI. Moreover, in symptomatic animals VCAM-MPIO binding was present in all regions showing Gd-DTPA enhancement and also in areas of no Gd-DTPA enhancement, which were confirmed histologically to be regions of leukocyte infiltration. VCAM-MPIO binding correlated significantly with increasing disability. Negligible MPIO-induced contrast was found in either EAE animals injected with an equivalent nontargeted contrast agent (IgG-MPIO) or in control animals injected with the VCAM-MPIO. These findings describe a highly sensitive molecular imaging tool that may enable detection of currently invisible pathology in MS, thus accelerating diagnosis, guiding treatment, and enabling quantitative disease assessment.     

Proteome analysis of brain in murine experimental autoimmune encephalomyelitis

Multiple sclerosis is considered a prototype inflammatory autoimmune disorder of the CNS. Experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein is one of the best‐characterized animal models of multiple sclerosis. Comprehensive understanding of gene expression in EAE can help identify genes that are important in drug response and pathogenesis. We applied a 2‐DE‐based proteomics approach to analyze the protein expression pattern of the brain in healthy and EAE samples. Of more than 1000 protein spots we analyzed, 70 showed reproducible and significant changes in EAE compared to controls. Of these, 42 protein spots could be identified using MALDI TOF‐TOF‐MS. They included mitochondrial and structural proteins as well as proteins involved in ionic and neurotransmitter release, blood barriers, apoptosis, and signal transduction. The possible role of these proteins in the responses of mice to animal models of multiple sclerosis is discussed.     

Dendritic cells induced in the presence of GM-CSF and IL-5

Experimental autoimmune encephalomyelitis (EAE) is commonly regarded as an animal model of the human disease multiple sclerosis (MS). Pertussis toxin (PTX) is routinely used for EAE induction in mice. Besides opening the blood-brain barrier, it acts as an adjuvant causing strong expansion of antigen-specific cells after coinjection with neuroantigens in IFA. Using an IL-17 ELISPOT assay we developed previously, we investigated the capability of PTX to induce proteolipid protein peptide 139-151(PLPp)-specific Th-17 cells in the immune periphery and in the thymus after coinjection with PLPp/IFA. PTX was found to induce peripheral PLPp-specific Th-17 cells in the draining lymph node and in the spleen, but not in the thymus. Our study indicates a new mechanism by which microbial agents can initiate or maintain autoimmune reactions and supports the growing role in particular for Th-17 cells in organ-specific autoimmune diseases like multiple sclerosis or EAE.     

Epitope spreading is not required for relapses in experimental autoimmune encephalomyelitis

The sequential emergence of specific T lymphocyte-mediated immune reactivity directed against multiple distinct myelin epitopes (epitope spreading) has been associated with clinical relapses in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Based on this association, an appealing and plausible model for immune-mediated progression of the advancing clinical course in MS and EAE has been proposed in which epitope spreading is the cause of clinical relapses in T cell-mediated CNS inflammatory diseases. However, the observed association between epitope spreading and disease progression is not universal, and absolute requirements for epitope spreading in progressive EAE have not been tested in the absence of multiple T cell specificities, because most prior studies have been conducted in immunocompetent mouse strains that possessed broad TCR repertoires. Consequently, the precise nature of a causal relationship between epitope spreading and disease progression remains uncertain. To determine whether relapsing or progressive EAE can occur in the absence of epitope spreading, we evaluated the course of disease in mice which possessed only a single myelin-specific TCR. These mice (transgenic/SCID +/+) exhibited a progressive and sometimes remitting/relapsing disease course in the absence of immune reactivity to multiple, spreading myelin epitopes. The results provide direct experimental evidence relevant to discussions on the mechanisms of disease progression in MS and EAE.     

In Vivo Quantification of Inflammation in Experimental Autoimmune Encephalomyelitis Rats Using Fluorine-19 Magnetic Resonance Imaging Reveals Immune Cell Recruitment outside the Nervous System

Progress in identifying new therapies for multiple sclerosis (MS) can be accelerated by using imaging biomarkers of disease progression or abatement in model systems. In this study, we evaluate the ability to noninvasively image and quantitate disease pathology using emerging “hot-spot” ¹⁹F MRI methods in an experimental autoimmune encephalomyelitis (EAE) rat, a model of MS. Rats with clinical symptoms of EAE were compared to control rats without EAE, as well as to EAE rats that received daily prophylactic treatments with cyclophosphamide. Perfluorocarbon (PFC) nanoemulsion was injected intravenously, which labels predominately monocytes and macrophages in situ. Analysis of the spin-density weighted ¹⁹F MRI data enabled quantification of the apparent macrophage burden in the central nervous system and other tissues. The in vivo MRI results were confirmed by extremely high-resolution ¹⁹F/¹H magnetic resonance microscopy in excised tissue samples and histopathologic analyses. Additionally, ¹⁹F nuclear magnetic resonance spectroscopy of intact tissue samples was used to assay the PFC biodistribution in EAE and control rats. In vivo hot-spot ¹⁹F signals were detected predominantly in the EAE spinal cord, consistent with the presence of inflammatory infiltrates. Surprising, prominent ¹⁹F hot-spots were observed in bone-marrow cavities adjacent to spinal cord lesions; these were not observed in control animals. Quantitative evaluation of cohorts receiving cyclophosphamide treatment displayed significant reduction in ¹⁹F signal within the spinal cord and bone marrow of EAE rats. Overall, ¹⁹F MRI can be used to quantitatively monitored EAE disease burden, discover unexpected sites of inflammatory activity, and may serve as a sensitive biomarker for the discovery and preclinical assessment of novel MS therapeutic interventions.     

Genetic analysis of disease subtypes and sexual dimorphisms in mouse experimental allergic encephalomyelitis (EAE): relapsing/remitting and monophasic remitting/nonrelapsing EAE are immunogenetically distinct

Experimental allergic encephalomyelitis (EAE) is the principal animal model of multiple sclerosis (MS), the major inflammatory disease of the central nervous system. Murine EAE is generally either an acute monophasic or relapsing disease. Because the clinical spectrum of MS is more diverse, the limited range of disease subtypes observed in EAE has raised concern regarding its relevance as a model for MS. During the generation of a large F2 mapping population between the EAE-susceptible SJL/J and EAE-resistant B10.S/DvTe inbred lines, we identified four distinct subtypes of murine EAE resembling clinical subtypes seen in MS. We observed acute progressive, chronic/nonremitting, remitting/relapsing, and monophasic remitting/nonrelapsing EAE. An additional subtype, benign EAE, was identified after histologic examination revealed that some mice had inflammatory infiltrates of the central nervous system, but did not show clinical signs of EAE. Genome exclusion mapping was performed to identify the loci controlling susceptibility to each disease subtype. We report three novel EAE-modifying loci on chromosomes 16, 7, and 13 (eae11-13, respectively). Additionally, unique loci with gender-specific effects govern susceptibility to remitting/relapsing (eae12) and monophasic remitting/nonrelapsing (eae7 and 13) EAE.