口服髓鞘碱性蛋白诱导免疫耐受治疗实验性自身免疫 …

目的 建立实验性自身免疫性脑脊髓炎（ＥＡＥ）动物模型,探讨口服自身抗原诱导免疫耐受对大鼠ＥＡＥ的防治作用。方法 在普通Ｗｉｓｔａｒ大鼠经１次足跖真皮内注射完全弗氏佐剂－豚鼠全脊髓匀浆或完全弗氏佐剂－髓鞘碱性蛋白乳剂加百日咳疫功诱发ＥＡＥ疾病;另在大鼠致炎前及发病后口服髓鞘碱性蛋白（ＭＢＰ）,观察其对ＥＡＥ的防治作用。     

嗅鞘细胞移植实验性自身免疫性脑脊髓炎后髓鞘碱性蛋白的表达和小胶质细胞的捕获

目的:研究嗅鞘细胞(OECs)移植实验性自身免疫性脑脊髓炎(EAE)后髓鞘碱性蛋白(Myelin basic protein,MBP)的表达及小胶质细胞捕获OECs情况。方法:用新生近交系Wistar大鼠嗅球培养出OECs,经荧光染料羧基荧光素二乙酸盐琥珀酰亚胺酯(CFSE)标记后注入同系EAE Wistar大鼠侧脑室,免疫组化检测OECs髓鞘碱性蛋白(MBP)、单核巨噬细胞诱导分子1(ED1)和CFSE共表达情况。结果:培养OECs不表达MBP,经侧脑室移植后在EAE大鼠脑内出现多量MBP+CFSE+细胞,同时在大脑广泛区域及血管周围间隙出现多量ED1+CFSE+细胞,与对照组相比差异显著。结论:OECs在EAE环境下表达MBP分子,其抗原能被脑内小胶质细胞或巨噬细胞捕获。     

口服MBP诱导免疫耐受预防实验性变态反应性脑脊髓炎的研究

目的：探讨口服耐受对实验性变态反应性脑脊髓炎(EAE)的预防作用。方法：给予健康Lewis大鼠口服MBP抗原诱导免疫耐受，随后以MBP CFA于足底免疫，检测口服耐受对实验大鼠EAE发病的预防作用及对MBP特异性淋转率、细胞因子和抗MBP抗体等免疫功能的变化情况。结果：致病组EAE发病率为91．7％，MBP特异性淋转率、IFN-γ与TNF-α含量升高，IL-10降低；口服耐受组EAE发病率为21．4％，MBP特异性淋转率、IFN-γ、TNF-α回复至正常，IL-10含量低于正常。MBP抗体水平两组均比正常对照组高。结论：口服耐受可降低宿主自身免疫反应性，减低EAE的发病率。     

在实验性自身免疫性脑脊髓炎模型中探讨MS的免疫耐受治疗

多发性硬化是一种较常见的中枢神经系统脱髓鞘疾病 ,T细胞介导免疫在其发病机制中起一定作用。该病的免疫耐受治疗是目前的研究热点之一 ,本文综述了近几年在其动物模型实验性自身免疫性脑脊髓炎中进行的研究工作的某些方法和进展。     

PM2.5短期暴露诱导免疫耐受缓解实验性自身免疫性脑脊髓炎的作用研究

目的：建立PM2.5短期暴露自身免疫性疾病动物模型,探讨PM2.5的“暴露时间窗”对小鼠实验性自身免疫性脑脊髓炎(EAE)发生发展的作用机制。方法：完全弗氏佐剂混合MOG_35-55免疫6周龄雌性C57BL/6小鼠构建EAE模型。对EAE小鼠进行PM2.5短期暴露,每天观察小鼠临床发病情况。组织学分析结合流式细胞术评估PM2.5短期暴露影响疾病发展的作用机制。结果：EAE小鼠临床评分显示,PM2.5短期暴露可显著延迟疾病发生发展。与对照组相比,PM2.5短期暴露组小鼠中枢神经系统(CNS)中观察到炎症和脱髓鞘显著减少。PM2.5短期暴露小鼠中枢及外周中激活的树突状细胞、巨噬细胞及致病性Th17细胞比例显著降低,有效抑制了CNS及外周炎症。结论：短期暴露于PM2.5环境对EAE小鼠病情具有一定缓解作用,可能通过抑制免疫细胞过度活化、诱导免疫耐受实现,阐明其机制可为自免疫疾病发病机制研究提供依据。     

细胞因子在实验性自身免疫性脑脊髓炎耐受中的作用

细胞因子(CK)在实验性自身免疫性脑脊髓炎(EAE)的免疫机制中起着重要作用。Th细胞的不同转化决定EAE的发生、发展或抑制。由多种CK构成的免疫调节网络操纵着Th细胞的免疫应答。通过作用Th细胞使之向抑制EAE方向转化,从而寻找对EAE耐受的途径,是目前EAE研究的一个重要方面。以下就与EAE耐受相关的CK研究进行综述,探讨EAE免疫病理机制。     

不同磷脂肽段诱导的实验性自身免疫性脑脊髓炎模型病理特征多样性的研究

目的:探索是否不同磷脂肽段可以诱导Lewis大鼠产生不同的病理学表现。方法:采用髓鞘碱性蛋白82-99(MBP82-99)、MBP68-86、髓鞘少突胶质细胞糖蛋白35-55(MOG35-55)免疫Lewis大鼠,每天进行神经功能评分。免疫后取各组大鼠大脑、小脑、脑干和脊髓组织,观察炎性细胞浸润部位和浸润程度、有无脱髓鞘和轴索损害。结果:MBP68-86和MBP82-99两组大鼠的大脑、脑干、小脑和脊髓组织均有炎性细胞浸润,脊髓炎症程度重于其他部位;MBP68-86和MBP82-99诱导的脊髓炎症程度无统计学差异;MOG35-55组大鼠仅脊髓组织受累,且炎症程度明显低于MBP组,其余各组未见炎性细胞浸润。各组大鼠神经组织均未见脱髓鞘和轴索受累。结论:不同磷脂肽段诱导Lewis大鼠神经组织炎性细胞浸润的分布和程度不同。     

经消化道诱导昆明鼠耐受实验性自身免疫性脑脊髓炎

诱导特异性免疫耐受是多发性硬化治疗学的一个重要研究方向。实验性自身免疫性脑脊髓炎是研究多发性硬化常用的动物模型，在此介绍我们使用同源脊髓匀浆诱导昆明鼠耐受实验性自身免疫性脑脊髓炎的一些实验工作结果及体会。     

在实验性自身免疫性脑脊髓炎模型中探讨MS？…

多发性硬化是一种较常见的中枢神经系统脱髓鞘疾病,Ｔ细胞介导免疫在其发病机制中起一定作用。该病的免疫耐受治疗是目前的研究热点之一,本文综述了近几年在其动物模型实验性自身免疫性脑脊髓炎中进行的研究工作的某些方法和进展。     

胸腺五肽治疗实验性自身免疫性脑脊髓炎的实验研究

目的 应用胸腺五肽(thymopentin,TP-5)干预实验性自身免疫性脑脊髓炎(experiment autoimmue encephalomyelitis,EAE)大鼠,探讨该药物对EAE的治疗作用及其机制.方法 以豚鼠全脊髓匀浆(guinea pig spinal cord homogenate,GPSCH)与完全弗氏佐剂(CFA)为抗原免疫Wistar大鼠建立EAE模型.Wistar大鼠随机分为正常对照组、EAE组、地塞米松(dexamethasone,DXM)组、TP-5小剂量组、TP-5大剂量组.采用双抗体夹心ELISA法检测Wistar大鼠免疫后7、14、21 d不同时间点血清中IL-12、IL-10的含量.结果 与EAE组和TP-5大剂量组比较,TP-5小剂量组和DXM组大鼠的发病率和临床评分显著性降低(P＜0.01);DXM组大鼠的发病率和临床评分低于TP-5小剂量组(P＜0.01).各个时间点EAE组、DXM组、TP-5小剂量组、TP-5大剂量组IL-12含量均较正常对照组明显升高(P＜0.01),免疫后14、21 d DXM组和TP-5小剂量组IL-12水平比EAE组低(P＜0.01);免疫后14、21 dDXM组、TP-5小剂量组IL-10水平与其余3组比较明显升高(P＜0.01).结论 TP-5对EAE有保护作用,其作用机制可能与上调IL-10水平以及下调IL-12水平有关,通过双向调节作用逆转TH1/TH2失衡.     

Spreading of the immune response to different myelin basic protein peptides in chronic experimental autoimmune encephalomyelitis in B10.RIII mice

B10.RIII mice develop chronic and relapsing experimental autoimmune encephalomyelitis (EAE) after immunization with the myelin basic protein (MBP) peptide 89-101 (VHFFKNIVTPRTP). To investigate the basis for the chronicity of the disease, the subsequent development of an immune responses to other parts of the MBP protein were investigated. Onset of disease occurs 9-25 days after immunization with MBP89-101. T cell responses towards a series of MBP peptides were assessed in an enzyme-linked immunospot assay detecting single cells secreting IFN-γ. There were responses not only to MBP89-101, but also towards peptides derived from sequences outside of MBP89-101. These peptides were of two kinds: those with sequences completely outside the 89-101 stretch of MBP; and those sharing a short sequence with MBP89-101 depending on alternative splicing of MBP mRNA. Immunization with these peptides also produced chronic EAE and a spreading of the immune response to other MBP peptides. Immunization with stepped peptides around the relevant region (MBP87-110) showed that peptides sharing a 6-amino-acid motif induced EAE after immunization. After MBP 89-101 peptide immunization, T cells isolated from lymph nodes did not cross-react in vitro to the other peptides sharing this motif. We suggest that one mechanism for the development of relapses during the disease course is the recruitment of new T cells with specificity for MBP peptides not derived from the peptide used for immunization. This is the first time such a mechanism has been demonstrated in a chronic autoimmune disease model.     

Antigen-driven tissue-specific suppression following oral tolerance: Orally administered myelin basic protein suppresses proteolipid protein-induced experimental autoimmune encephalomyelitis in the SJL mouse

Immunomodulatory treatment paradigms have been applied to animal models of T cell-mediated autoimmune diseases in an attempt to develop an immunospecific and non-toxic form of therapy which can be applied to humans. These treatment paradigms are often directed to T cells with a restricted T cell receptor repertoire or that react with dominant peptide determinants. Experimental data, however, suggests that even if the initial T cell response is restricted to a specific self-protein in the target organ, spreading autoimmunity may develop with broadening of T cell autoreactivity to additional epitopes of the same autoantigen or to different autoantigens in the target organ. Thus, multiple autoantigens may become targets of the autoimmune response. This makes immunotherapeutic strategies based on suppressing responses to restricted proteins or clones of cells problematic. We have previously shown that suppression of experimental autoimmune encephalomyelitis (EAE) in the Lewis rat by oral myelin basic protein (MBP) is mediated by the release of transforming growth factor-β after triggering by the oral tolerogen. Here, we report that in the SJL model of EAE oral administration of an autoantigen from the target tissue suppresses disease independent of whether it is or is not the inciting antigen. Thus, orally administered MBP or MBP peptides suppress proteolipid protein (PLP)-induced EAE, whereas intravenously administered MBP does not. Both oral and intravenous PLP, however, suppressed PLP disease. These findings have important implications for the use of oral tolerance as a therapeutic approach for the treatment of T cell-mediated inflammatory autoimmune diseases in man in which the inciting autoantigen is unknown or in which there is autoreactivity to multiple autoantigens in the target tissue.     

Orally administered myelin basic protein in neonates primes for immune responses and enhances experimental autoimmune encephalomyelitis in adult animals

Antigen-driven tolerance is an effective method for suppression of autoimmune diseases. Adult animals can be tolerized against the induction of experimental autoimmune encephalomyelitis (EAE) by both oral and parenteral administration of myelin basic protein (MBP). We have found that in contrast to previous studies of neonatal tolerance in which parenterally administered autoantigens induced tolerance, the oral administration of MBP in neonatal rats did not result in tolerization to MBP, but instead, primed for immunologic responses. Proliferative responses to MBP and its encephalitogenic epitope were present in animals fed with MBP as neonates and co-culture of encephalitogenic T cells with cells from neonatal rats fed with MBP were associated with enhanced MBP responses rather than the suppression observed with cells from adult rats fed with MBP. Furthermore, neonates fed with MBP and immunized 6–8 weeks later with MBP in adjuvant to induce EAE revealed enhancement of disease severity, and were not protected from a second attack upon active reinduction of EAE. Subcutaneous injection of soluble MBP into neonates had no effect on EAE induction as adults, whereas intraperitoneal injection of MBP in neonates was associated with marked suppression of disease in adults. Suppression of EAE began to appear in animals fed with MBP at 4 weeks of age, and was similar to oral tolerance in adult animals when animals were fed at 6 weeks of age. These results suggest that immaturity of the immunoregulatory network associated with oral tolerance and sensitization to autoantigens via the gut in the neonatal period may contribute to the pathogenesis of autoimmune diseases.     

Synapsin-induced proliferation of T-cell lines against myelin basic protein obtained from rats with experimental autoimmune encephalomyelitis

We have previously described that antibodies and T cells against myelin basic protein (MBP) rose under conditions to induce acute experimental autoimmune encephalomyelitis (EAE) bind other proteins present in the synaptosomal fraction, some of them identified as synapsin I. The aim of this study was to evaluate whether anti-MBP T-cell lines can be also activated by synapsin. The analysis of rat anti-MBP T-cell lines cultured with each antigen showed that these cells responded also to purified rat synapsin and to the amino terminal portion of this protein. This recognition originated a proliferative response with a concomitant pattern of cytokine secretion similar to that induced by MBP itself implicating that this recognition would be mediated by the T-cell receptor. On the other hand, anti-synapsin T-cell lines were not capable of responding to MBP stimulation. Therefore, the immunological cross-reactivity between both proteins occurs only in one direction and these cross-reactive cells would be elicited only in animals sensitized with MBP. A possible implication of immunological agents against MBP cross-reactive with extra-myelin proteins in the process of EAE is considered.     

Transplantation of autoimmune regulator-encoding bone marrow cells delays the onset of experimental autoimmune encephalomyelitis

The autoimmune regulator (AIRE) promotes "promiscuous" expression of tissue-restricted antigens (TRA) in thymic medullary epithelial cells to facilitate thymic deletion of autoreactive T-cells. Here, we show that AIRE-deficient mice showed an earlier development of myelin oligonucleotide glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE). To determine the outcome of ectopic Aire expression, we used a retroviral transduction system to over-express Aire in vitro, in cell lines and in bone marrow (BM). In the cell lines that included those of thymic medullary and dendritic cell origin, ectopically expressed Aire variably promoted expression of TRA including Mog and Ins2 (proII) autoantigens associated, respectively, with the autoimmune diseases multiple sclerosis and type 1 diabetes. BM chimeras generated from BM transduced with a retrovirus encoding Aire displayed elevated levels of Mog and Ins2 expression in thymus and spleen. Following induction of EAE with MOG(35-55), transplanted mice displayed significant delay in the onset of EAE compared with control mice. To our knowledge, this is the first example showing that in vivo ectopic expression of AIRE can modulate TRA expression and alter autoimmune disease development.     

Epicutaneous (EC) immunization with myelin basic protein (MBP) induces TCRalphabeta+ CD4+ CD8+ double positive suppressor cells that protect from experimental autoimmune encephalomyelitis (EAE)

Multiple sclerosis (MS) is a central nervous system (CNS) chronic inflammatory autoimmune disease with limited treatment modalities. Oral tolerance is one of the experimental methods that protects from autoimmune diseases. However, this method failed to be therapeutic in clinical trials. In our previous work we found that epicutaneous (EC) immunization with protein antigen induced a state of profound immunosuppression that inhibited inflammatory response in contact sensitivity, in experimental autoimmune encephalomyelitis (EAE) and in allogeneic skin graft rejection. In our current work, we precisely determined the phenotype of EC induced T suppressor (Ts) cells that reduce the progress of EAE. Employing TCRdelta-/-, CD1d-/- mice, we showed that EC induced Ts cells do not belong either to the population of TCRgammadelta cells or CD1d restricted NKT cells. Moreover, we noticed that a lack of CD1d-/- restricted NKT lymphocytes resulted in the induction of much stronger suppression of EAE than in wild type mice. This might suggest that NKT cells could interfere with the induction of Ts cells. Using beta2m-/- mice, negative selection and positive selection of EC induced Ts cells, we showed that Ts cells protecting from EAE belong to the population of TCRalphabeta+ CD4+ CD8+ double positive lymphocytes.     

Exacerbation of experimental autoimmune encephalomyelitis in rodents infected with murine gammaherpesvirus-68

Viral infections have long been suspected to play a role in the pathogenesis of multiple sclerosis. In the present study, two different rodent models of experimental autoimmune encephalomyelitis (EAE) were used to demonstrate the ability of murine gammaherpesvirus-68 (gammaHV-68) to exacerbate development of neurological symptoms. SJL mice received UV-inactivated gammaHV-68 or intranasalgammaHV-68, followed by immunization against proteolipid-protein peptide 139-151. Infected mice became moribund within 10 days post-immunization, whereas mice exposed to UV-inactivated gammaHV-68 recovered. In the second model, Lewis rats were exposed to UV-inactivated gammaHV-68 or to gammaHV-68, followed by passive transfer of encephalitogenic T lymphocytes specific for myelin basic protein. Consistently, infected rats had higher clinical scores, and this result was observed during acute or latent gammaHV-68 infection. It is unlikely that this gammaHV-68-induced exacerbation was due to significant viral replication within the central nervous system since nested PCR, viral plaque assays, and infectious-centers assays demonstrated no detectable virus in spinal cords or brains of infected rodents undergoing EAE. Taken together, these studies demonstrate increased clinical symptoms of EAE in rodents infected by a gammaherpesvirus that has a limited ability to invade the central nervous system.     

Combined nasal administration of encephalitogenic myelin basic protein peptide 68-86 and IL-10 suppressed incipient experimental allergic encephalomyelitis in Lewis rats

Mucosal administration of low doses of myelin basic protein (MBP) peptide 68-86 (MBP 68-86) or anti-inflammatory cytokine IL-10 effectively prevented experimental allergic encephalomyelitis (EAE), but failed to suppress the disease if given after 7 days postimmunization (p.i.), i.e., after T cell priming had occurred. We anticipated that combined administration of autoantigen and IL-10 can treat incipient EAE. Lewis rats with EAE actively induced with MBP 68-86 and complete Freund's adjuvant received 120 microg MBP 68-86 + 200 ng IL-10 per rat per day from day 7 p.i. and for 5 consecutive days. These rats showed later onset, lower clinical scores, less body weight loss, and shorter duration of EAE than rats receiving MBP 68-86 or IL-10 only or PBS. EAE amelioration was associated with decreased infiltration of ED1(+) macrophages and CD4(+) T cells within the central nervous system and with decreased proliferative responses of lymph node cells, indicating that combined administration of MBP 68-86 and IL-10 induced immune hyporesponsiveness. IFN-gamma secretion as well as IFN-gamma, TNF-alpha, IL-4, and IL-10 mRNA expression by lymph node MNC was down-regulated in the treated rats. Immune hyporesponsiveness, rather than immune deviation or regulatory mechanisms, seems to be responsible for the protection of EAE after autoantigen + IL-10 administration by the nasal route.