雌激素在实验性自身免疫性脑脊髓炎中的保护作用

多发性硬化(multiple sclerosis,MS)与其他多种自身免疫性疾病一样存在着性别差异,表现为:与男性相比,女性发病率较高,且初发时间也较早。女性患者在妊娠期伴随着体内雌激素水平的波动,MS患者复发次数和严重程度也出现明显变化[1]。在MS动物模型即实验性自身免疫性脑脊髓炎(exp     

实验性自身免疫性脑脊髓炎小鼠的磁共振研究

目的研究动物模型实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)小 鼠中枢神经系统的MR表现。方法使用PLP139-151免疫接种雌性SJL／J小鼠诱导EAE。分别取复发期和缓解期 的EAE小鼠行脑和脊髓常规MR及Gd—DTPA增强MR扫描,并做组织病理学检查。结果PLP139-151能较好的诱 导出慢性复发-缓解型EAE模型,Gd-DTPA增强MR检查能充分显示血脑屏障的破坏,反映脑和脊髓的病灶,而且 显示的病灶相对信号强度复发期明显高于缓解期,在病灶处均可见炎症细胞浸润,髓鞘脱失,病灶周围或远离病灶 处炎症反应轻微。结论Gd—DTPA增强MR检查能准确反映血脑屏障的破坏,病变累及部位及病变程度,为今后使 用药物干预EAE判断疗效、指导进行较准确的病变部位取材时提供了一种更为客观的手段。     

雌激素抑制实验性自身免疫性脑脊髓炎大鼠的NF-κB和Rho激酶表达

目的 探讨雌激素对实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)大鼠中枢神经系统NF-κB和Rho激酶表达的影响及相关作用机制.方法 60只雌性Wistar大鼠行卵巢摘除术后建立EAE模型,随机分为模型组、对照组、雌激素组和NF-κB特异性抑制剂吡咯烷二硫代氨基甲酸盐(pyrro-lidine dithocarbamate,PDTC)组,每组15 只.自免疫日起,雌激素组给予17β-雌二醇20 μg/(kg·d),连续10 d;PDTC组注射PDTC 50 mg/(kg·d),连续10 d.免疫后16天统一处死取脑组织,HE染色观察炎性细胞浸润情况,免疫组化和Western blot 观察NF-κB p65和Rho激酶表达的变化.结果 与模型组比较,雌激素组发病率无统计学差异(P>0.05),但发病潜伏期延长(P<0.05),神经功能评分较低(P<0.05);HE染色示雌激素组和PDTC组脑组织炎性细胞浸润程度较模型组轻;免疫组化和Western blot 结果示,与模型组相比,雌激素组和PDTC 组NF-κB和Rho激酶表达均较低(P<0.01).结论 雌激素能抑制EAE大鼠NF-κB和Rho激酶的表达,其对Rho激酶的抑制作用可能部分通过下调NF-κB的水平实现的.     

雄激素在实验性自身免疫性脑脊髓炎中的保护作用

多发性硬化(multiple sclerosis, MS)及其动物模型即实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)都具有性别差异,但其确切机制仍不清楚.近年来,大量研究发现雄激素与EAE的发病和病程有一定关系.此文就EAE存在的性别差异及雄激素在其中的作用做一综述.     

实验性自身免疫性脑脊髓炎的历史和现状

<正> 多发性硬化(multiple sclerosis,MS)是一种中枢神经系统(central nervous system,CNS)炎性脱髓鞘性自身免疫性疾病,其确切的发病机制仍不清楚,研究MS的实验动物模型成为探索该病病因学的最佳途径和方法。MS的实验动物模型主要分为免疫介导模型和病毒诱导模型两种,其中以免疫介导模型多用,该模型主要是通过注射CNS髓鞘蛋白(或分子肽段)与抗原佐剂的乳化复合物诱导动物对抗原反     

实验性自身免疫性脑脊髓炎的视神经病理改变

目的 研究实验性自身免疫性脑脊髓炎(EAE)的视神经病理改变.方法 足垫皮下注射豚鼠脊髓匀浆和完全弗氏佐剂(CFA)混合物制作Wismr大鼠EAE模型,于发病后第6d将大鼠处死,取视神经、脑和脊髓,行HE和LFB染色,光镜和电镜下观察其病理改变.结果 病理检查发现EAE模型组大鼠脑、脊髓有不同程度的炎症反应和脱髓鞘改变;均有视神经病变,光镜主要表现为炎症反应和脱髓鞘,视神经髓鞘脱失重于炎症反应;电镜主要表现为髓鞘稀疏,少突胶质细胞数量减少、胞核固缩,其周围包裹的髓鞘板层松解,轴突髓鞘分离.结论 EAE大鼠存在明显的视神经病变,主要为视神经炎症反应和脱髓鞘改变.     

一氧化氮供体对实验性自身免疫性脑脊髓炎的作用

目的探讨一氧化氮供体3-吗啉-斯德酮亚胺(3-morpholinosydnonimine,SIN-1)对实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)大鼠的作用。方法应用豚鼠髓鞘碱性蛋白68-86(myelin basic protein 68-86,MBP68-86)主动免疫制作EAE实验动物模型。将大鼠随机分为SIN-1组和对照组,SIN-1组大鼠于致敏后第0~7天给予SIN-1药物干预,动态观察两组大鼠的临床症状及体质量变化,致敏后第14天采用ELISA方法检测各组大鼠单个核细胞(mononuclear cells,MNC)培养上清中γ干扰素(IFN-γ)和白细胞介素-4(IL-4)水平,并观察大鼠脑组织病理变化。结果与对照组比较,SIN-1组大鼠发病时间延迟,恢复时间提前,体质量明显增加,临床症状明显减轻;疾病症状最高评分明显降低。SIN-1组大鼠MNC培养上清中IFN-γ水平为(90.29±9.07)pg/mL,较对照组的(121.57±10.44)pg/mL明显降低(P<0.05);IL-4水平为(18.14±3.98)pg/mL,较对照组的(8.14±1.95)pg/mL明显增加(P<0.05)。SIN-1组大鼠组织病理损伤较对照组明显减轻。结论一氧化氮供体SIN-1可抑制EAE大鼠病情发展,对EAE具有保护作用。     

TLR9与实验性自身免疫性脑脊髓炎

Toll样受体9(toll-like receptor 9,TLR9)通过识别细菌和病毒DNA中未甲基化的胞嘧啶-磷酸-鸟嘌呤(CpG DNA)序列激活天然免疫应答和获得性免疫应答,从而促进宿主抵抗感染性疾病。但一定条件下,TLR9活化亦可促发某些自身免疫性疾病如实验性自身免疫性脑脊髓炎(EAE)。该文就TLR9的结构、配体、信号转导通路及TLR9在EAE中的作用机制进行综述。     

地塞米松对实验性自身免疫性脑脊髓炎小鼠IL-17表达的影响

目的研究地塞米松对实验性自身免疫性脑脊髓炎(EAE)小鼠脑及脊髓组织中IL-17表达水平及脾组织中Th17细胞比例的影响。方法将33只C57BL/6小鼠随机分为对照组、EAE组和地塞米松组。EAE组及地塞米松组小鼠以MOG35-55进行免疫造模。地塞米松组小鼠自免疫当天至处死,隔日给予地塞米松磷酸钠注射液0.07mg·kg~(-1)腹腔注射。对照组及EAE组给予等量生理盐水。观察小鼠的发病情况及神经功能评分。应用苏木精-伊红染色、免疫组织化学染色、实时定量PCR、流式细胞学方法分别检测小鼠中枢神经系统炎症细胞浸润、IL-17阳性细胞表达、IL-17m RNA水平及脾组织Th17细胞比例。结果地塞米松组与EAE组比较,小鼠发病率及神经功能评分明显降低(P0.05)。与对照组比较,EAE组小鼠脑及脊髓组织中炎性病灶数明显增多(P0.05),IL-17阳性细胞数明显增多(P0.05),脊髓组织中IL-17m RNA水平明显升高(P0.05),脾组织Th17细胞比例明显升高(P0.05);与EAE组相比较,地塞米松组小鼠脑、脊髓及脾组织中上述指标明显降低(P0.05)。结论地塞米松可以降低EAE小鼠发病率,减轻发病时神经功能损伤程度以及脑和脊髓内炎性细胞浸润程度,并使IL-17mRNA、蛋白表达水平及Th17细胞比例下降。其神经保护作用可能是通过抑制IL-17/IL-23轴等免疫调节机制而实现。     

雌激素受体α对实验性自身免疫性脑脊髓炎小鼠TIMP-1及TIMP-2表达的影响

目的 以实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)作为多发性硬化(multiple sclerosis,MS)的动物模型,初步探讨雌激素和雌激素受体α(estrogen receptor α,Erα)在EAE中的抗炎作用及其作用机制.方法 在小鼠侧脑室立体定位注射Erα重组慢病毒,鉴定Erα重组慢病毒在体感染中枢神经系统(central nervous system,CNS)的最佳剂量.将雌二醇及Erα重组慢病毒干预EAE小鼠与对照组比较,观察 各组小鼠的临床症状及体重的变化,通过H&E染色及Luxol fast blue-H&E染色对比各组炎症反应及脱髓鞘情况,以实时荧光定量PCR及Western blot方法检测金属蛋白酶组织抑制因子-1(tissue-inhibitors of matrix metalloproteinase-1,TIMP-1)及TIMP-2.结果 15μl Erα重组慢病毒能感染小鼠CNS.与对照组相比,雌二醇及过表达Erα可以降低EAE小鼠的发病率、体重丢失及临床症状,减轻脑和脊髓中炎性细胞浸润和神经纤维的髓鞘脱失,在发病急性期增加TIMP-1及TIMP-2,减轻在缓解期TIMP-1、TIMP-2的病理性表达增高.结论 雌激素及Erα可以抑制EAE的炎症反应,该作用机制可能是通过增加EAE小鼠急性发病期脑组织中TIMP-1及TIMP-2实现的.     

小鼠实验性自身免疫性脑脊髓炎的病理变化

目的用髓鞘少突胶质细胞糖蛋白多肽(MOG35-55)诱发实验性自身免疫性脑脊髓炎(experi-m ental autoimmune encephalomyelitis,EAE)小鼠模型。方法应用MOG35-55抗原加完全弗氏佐剂免疫C57BL/6小鼠,利用光镜、电镜观察小鼠组织学改变。结果光镜下可见小血管周围炎细胞浸润,呈袖套状改变、血管周围明显脱髓鞘及神经元变性,B ieschowsky银染显示大量轴索肿胀和轴索卵形体的形成,电镜下可见髓鞘结构松散、断裂或融合,包括不同程度的髓鞘重建,脊髓病变广泛,程度重于脑部。结论EAE的病理改变为血管周围炎性细胞浸润、白质脱髓鞘及髓鞘重建。     

Variation in experimental autoimmune encephalomyelitis scores in a mouse model of multiple sclerosis

Multiple sclerosis (MS) is a common demyelinating central nervous system disease associated with progressive physical impairment. To study the mechanism underlying disease pathogenesis and develop potential treatments, experimental autoimmune encephalomyelitis (EAE) is often used as an animal model. EAE can be induced in various species by introducing specific antigens, which ultimately result in motor dysfunction. Although the severity of the paralysis is indicated using the EAE score, there is no standard scoring system for EAE signs, and there is variability between research groups with regard to the exact EAE scoring system utilized. Here, we describe the criteria used for EAE scoring systems in various laboratories and suggest combining EAE score with another quantitative index to evaluate paralysis, such as the traveled distance, with the goal of facilitating the study of the mechanisms and treatment of MS.     

Regulation of experimental autoimmune encephalomyelitis: Inhibition of adoptive experimental autoimmune encephalomyelitis by ‘recovery-associated suppressor cells’

We have previously shown the presence of suppressor cells in Lewis rats at the time of spontaneous recovery from experimental autoimmune encephalomyelitis (EAE). These cells, called ‘recovery-associated suppressor cells’ (RASC), are capable of preventing active EAE and inhibiting in vitro the specific proliferative response of encephalitogenic anti-MBP T cell line cells. The present investigations were undertaken in order to lend support to the hypothesis that RASC play an active role in the recovery. We found that RASC can prevent adoptive EAE when admixed with already activated, but not resting, anti-MBP T cells or when injected into the recipients separately from the encephalitogenic cells. They can also arrest the course of an ongoing disease when injected after the beginning of the clinical signs. This study provides the first direct demonstration of the downregulation of an ongoing EAE by suppressor cells.     

Activation of mitogen-activated protein kinases in experimental autoimmune encephalomyelitis

The expression of mitogen-activated protein (MAP) kinases, including extracellular signal-regulated kinase (ERK), c-Jun NH(2)-terminal protein kinase (JNK), and p38, was analyzed in experimental autoimmune encephalomyelitis (EAE) in rats.

Western blot analysis showed that the three MAP kinases (phosphorylated ERK (p-ERK), p-JNK, and p-p38) were increased significantly in the spinal cords of rats with EAE at the peak stage as compared with the levels in controls (p<0.05), and both p-ERK and p-JNK declined slightly in the recovery stage of EAE. Immunohistochemistry showed that p-ERK was constitutively expressed in brain cells, including astroglial cells, and showed enhanced immunoreactivity in those cells in EAE, while some T cells and macrophages were weakly immunopositive for p-ERK in EAE lesions. Both p-JNK and p-p38 were intensely immunostained in T cells in EAE lesions, while a few glial cells and astrocytes were weakly positive for both.

Taking all these facts into consideration, we postulate that increased expression of the phosphorylated form of each MAP kinase plays an important role in the initiation of acute monophasic EAE. Differential expression of three MAP kinases was discerned in an animal model of human autoimmune central nervous system diseases, including multiple sclerosis.     

MK-801对EAE动物模型轴索损伤的保护作用研究

目的通过建立实验性自身免疫性脑脊髓炎(EAE)动物模型,对EAE的发病机制和轴索损伤进行研究,并进行药物干预,寻找新的治疗方法。方法选用髓鞘蛋白脂蛋白(PLP139-151)多肽作为抗原免疫雌性SJL/J小鼠,诱发EAE小鼠模型,应用MK-801(0.30mg/kg)进行干预。发病后取脑、脊髓组织切片,进行免疫组织化学检查。结果模型组23(23/30)只小鼠发病,发病率为76.7%,平均发病时间为19±2.58天,平均神经功能评分为2.14±0.69分。药物(MK-801)治疗组16(16/30)只小鼠发病,发病率为53.3%,平均发病时间为21±1.25天(P<0.05),平均神经功能评分为1.08±0.42分(P<0.02);病理显示药物干预后病灶减少,病变减轻。结论PLP多肽诱发SJL/J小鼠的EAE动物模型的病理改变主要累及脊髓。谷氨酸的兴奋性毒性参与MS发病和轴索损伤,应用NMDA受体拮抗剂MK-801可以减少神经功能缺失,降低发病率。     

实验性自身免疫性脑脊髓炎大鼠模型脑组织硫化氢的变化

目的 观察实验性自身免疫性脑脊髓炎(EAE)模型大鼠脑组织中硫化氢(H2S)动态变化,探讨H2S与多发性硬化(MS)的关系. 方法 按随机区组设计方法将SD大鼠分成对照组及模型组,每组78只.模型组制备EAE模型,对照组用生理盐水代替诱导乳剂,余措施相同.采用HE染色、尼氏染色观察2组大鼠脑组织病理变化;比较不同时间点(建模后5、10、15、20、25、30、35、40、45、50、55、60 d和65 d)2组大鼠平均临床评分;采用比色法检测各时间点H2S和丙二醛(MDA)水平. 结果 (1)HE和尼氏染色显示模型组中可见明显的炎性细胞浸润现象及血管袖套形成,对照组未发现明显改变.(2)模型组于建模后第20天及第50天出现2次发病高峰,临床评分分别为(4.0±0.55)分和(3.5±0.25)分;对照组的评分为0分.(3)模型组大鼠各时间点脑组织中H2S表达量随着发病呈逐渐下降趋势,从第10天开始低于对照组,差异有统计学意义(P＜0.05).相反,模型组大鼠各时间点脑组织中MDA呈逐渐增加趋势,从第10天开始高于对照组,差异有统计学意义(P＜0.05).对照组大鼠H2S和MDA水平无明显变化.(4)模型组大鼠脑组织中H2S水平的变化与临床评分、MDA水平呈负相关(r=0.960,P=0.000;r=-0.920,P=0.000);临床症状评分和MDA水平呈正相关(r=0.910,P=0.000). 结论 H2S在EAE模型中表达明显降低,在MS中的作用机制有待进一步研究.     

辛伐他汀抑制大鼠实验性自身免疫性脑脊髓炎的实验研究

目的 探讨辛伐他汀(STATINS)对实验性自身免疫性脑脊髓炎IEAE)的作用及机理.方法 Wistar大鼠55只采用随机数字表法分为EAE组(15只)、STATINS组(15只)、雷公藤(TP)组(15只)、正常对照组(10只).使用STATINS干预EAE大鼠,以TP为阳性对照,观察大鼠P53蛋白、IL-6、TNF-α、TGF-β的表达变化.结果 与EAE组相比,STATINS组发病率降低、临床症状减轻、体质量下降减少、病灶数减少、潜伏期延长,而TP组临床症状减轻、病灶数减少,差异均有统计学意义(P＜0.05),TP组体质量变化、潜伏期、发病率无显变化,差异无统计学意义(P＞0.05);STATINS组IL-6和TNF-α的表达降低,P53蛋白和TGF-β的表达增高;TP组仅TNF-α的表达降低,差异均有统计学意义(P＜0.05).与TP组相比较,STATINS组P53蛋白与TGF-β的表达增加,差异有统计学意义(P＜0.05),而TNF-α及Ⅱ-6的表达差异无统计学意义(P＞0.05).结论 STATINS可以有效抑制EAE.其可能的机制是抑制IL-6和TNF-α等促炎症因子的表达,促进P53蛋白与TGF-β的表达,效果可能优于TP.     

Phagocytosis of apoptotic lymphocytes by oligodendrocytes in experimental autoimmune encephalomyelitis

The alterations in oligodendrocytes in myelin basic protein-induced acute experimental autoimmune encephalomyelitis (EAE) in the Lewis rat were studied using the technique of pre-embedding immunolabelling with the Rip monoclonal antibody, which specifically labels the cytoplasm of the cell bodies and processes of oligodendrocytes. In spinal cord sections of untreated and dexamethasone-treated rats with EAE, we found that apoptotic lymphocytes were phagocytosed by Rip-positive oligodendrocytes as well as by CD11b/c-positive macrophages/ microglia and by astrocytes expressing glial fibrillary acidic protein. Morphologically normal lymphocytes were also internalised by these cell types, a phenomenon known as emperipolesis. We suggest that this phenomenon represents the phagocytosis of lymphocytes that have undergone the plasma membrane alterations of apoptosis without yet manifesting the nuclear condensation of apoptosis. We also found an increase in the number of clusters of two to four oligodendrocytes, mainly in the grey matter, suggesting proliferation of cells of the oligodendrocyte lineage. Received: 14 March 1997 / Revised: 4 August 1997 / Accepted: 8 August 1997