实验性自身免疫性脑脊髓炎豚鼠鼻粘膜免疫耐受研究

目的　探讨鼻粘膜摄入髓鞘碱性蛋白（ＭＢＰ） 抗原诱导免疫耐受，在抑制实验性自身免疫性脑脊髓炎（ＥＡＥ）的发生中的作用及其机制。方法　先使豚鼠经鼻粘膜摄入ＭＢＰ，诱导建立外周免疫耐受，然后用ＭＢＰ加完全弗氏佐剂（ＣＦＡ） 免疫豚鼠，观察动物的临床症状、Ｅ花环形成试验、淋巴细胞转化试验、迟发型超敏反应（ＤＴＨ） 、细胞因子水平及病理改变。结果　鼻粘膜免疫耐受可有效地阻止ＥＡＥ发生，耐受组动物Ｅ花环形成试验、淋巴细胞转化试验及ＤＴＨ反应明显受到抑制，外周血淋巴细胞培养后测得白细胞介素４ （ＩＬ４） 水平明显升高，γ干扰素（ＩＦＮγ） 水平则明显降低。结论经鼻粘膜摄入小量自身抗原是诱导疾病免疫耐受的有效途径，可能为多种自身免疫病的防治提供有希望的方法。推测鼻粘膜免疫耐受可能与Ｔｈ１ 反应及促炎症性细胞因子，如ＩＦＮγ分泌下调、Ｔｈ２ 反应及抗炎症性细胞因子，如ＩＬ４ 分泌上调有关。     

多发性硬化症髓鞘素组分特异性抗体分泌细胞

本文用酶联免疫斑点法（Ｅｌｉｓｐｏｔ）检测了２３例临床确诊多发性硬化症（ＭＳ）和１２例无菌性脑膜炎（ＡＭ）患者外周血（ＰＢ）和脑脊液（ＣＳＦ）中髓鞘素碱性蛋白（ＭＢＰ）、髓鞘素结合糖蛋白（ＭＡＧ）和含脂质蛋白（ＰＬＰ）特异性ＩｇＧ抗体分泌细胞。两组患者ＣＳＦ中该３种抗体分泌细胞均呈明显增多趋势，ＭＳ组尤著，但两组ＰＢ中该类细胞数均很少。指示对髓鞘素组分的Ｂ细胞免疫应答主要局限于与中枢神经系统（ＣＮ     

急性脑梗塞患者分泌γ—干扰素的特异性髓鞘素记忆性T细胞的研究

通过计数分泌细胞因子γ－干扰素记忆性Ｔ细胞，观察急性脑梗塞（ＡＣＩ）患者的特异性Ｔ细胞免疫应答。方法采用酶联免疫斑点法（ＥＬＩＳＡ）检测了３２例ＡＣＩ、２４例炎症性神经疾病（ＯＩＮＤ）和２５例其他神经疾病（ＯＮＤ）患者髓鞘素抗原及其多肽应答性Ｔ细胞。结果ＡＣＩ患者外周血髓鞘素碱性蛋白（ＭＢＰ）及其多肽和含脂质蛋白（ＰＬＰ）自身抗原应答性Ｔ细胞数呈显著增高，脑脊液（ＣＳＦ）中ＭＢＰ应答性Ｔ细胞数约为外周血中的１１０倍。结论这种免疫应答可能是继发于急性缺血后的脑组织损伤，且在紧邻靶器官的ＣＳＦ中表现尤为明显，其病理意义还有待进一步探讨。     

Alzheimer型痴呆的髓鞘素蛋白自身应答性T细胞免疫反应

通过计数分泌细胞因子γ－干扰素（ＩＦＮ－γ）、辅助性Ｔ细胞（Ｔｈ１），检查ＡＤ患者外周血和脑脊液（ＣＳＦ）中Ｔ细胞免疫应答。方法：将单个核细胞（ＭＮＣ）暴露于中枢神经系统（ＣＮＳ）髓鞘素抗原髓鞘碱性蛋白（ＭＢＰ）和含脂质蛋白（ＰＬＰ）中进行体外短时间培养，用酶联免疫斑点试验（Ｅｌｉｓｐｏｔ）检测ＩＦＮ－γ分泌性Ｔｈ１细胞链，同时检测急性脑血管病（ＣＶＤ）和其他神经疾病（ＯＮＤ）患者作为对照。结果显示ＡＤ患者外周血中呈高水平ＭＢＰ应答性Ｔｈ１细胞链，而其ＣＳＦ中尤为明显，外周血中ＰＬＰ应答性Ｔｈ１细胞亦显著高于ＯＮＤ对照组。结论认为ＡＤ患者存在高水平的髓鞘素蛋白自身应答性Ｔ细胞反应，且在与ＣＮＳ紧邻的ＣＳＦ中表现得尤为显著，其在ＡＤ发病机制中的作用还有待进一步深入探讨。     

发作性头痛者动态脑电图监测的价值

目的 探讨发作性头痛者２４ｈ动态脑电图（ＡＥＥＧ）监测的价值。方法 对１２０例发作性头痛患者进行２４ｈＡＥＥＧ监测，分析发作期和间期脑电活动特点，并与常规ＥＥＧ作自身对照。结果 ＡＥＥＧ非特异性异常５４例（４５％），捕捉到痫样放电１１例（９．２％），ＥＥＧ非特异性异常３１例（２５．８％），捕捉到痫样放电仅４例（３．３％），ＡＥＥＧ异常率（５４．２％）明显高于ＥＥＧ（２９．２％）。ＡＥＥＧ痫样放电多     

急性脑梗死和Alzheimer病脑脊液高水平髓鞘素抗原B细胞免疫应答

目的确认急性脑梗死（ＡＣＩ）和Ａｌｚｈｅｉｍｅｒ病（ＡＤ）对髓鞘素碱性蛋白（ＭＢＰ）、髓鞘素结合糖蛋白（ＭＡＧ）和含脂质蛋白（ＰＬＰ）的Ｂ细胞免疫应答。方法采用酶联免疫斑点技术检测了ＡＣＩ、临床可能ＡＤ和其它神经疾病（ＯＮＤ）对照组患者外周血和脑脊液（ＣＳＦ）中ＭＢＰ、ＭＡＧ和ＰＬＰ抗体分泌细胞。结果ＡＣＩ、ＡＤ和ＯＮＤ患者外周血中均可检出ＩｇＧ、ＩｇＡ、ＩｇＭ三种表型ＭＢＰ、ＭＡＧ、ＰＬＰ抗体分泌细胞，无显著差异。但ＡＣＩ和ＡＤ患者ＣＳＦ中ＩｇＧ型ＭＢＰ、ＭＡＧ和ＰＬＰ抗体分泌细胞均呈显著性增高。结论ＡＣＩ急性脑缺血损伤和ＡＤ神经变性可能导致体内Ｂ细胞激活及ＣＮＳ内髓鞘素反应性Ｂ细胞免疫应答，其病理意义有待探讨。     

大鼠单侧颈动脉阻断所致的脑缺血性损害和764—3脑保…

采用三种方式暂时阻断大鼠单侧颈动脉（ＣＡ）：阻断颈总动脉（ＣＣＡ），阻断颈内动脉（ＩＣＡ），阻断ＣＣＡ，ＩＣＡ和颈外动脉（ＥＣＡ）。此三种阻断方式可造成脑缺血性损害，但不引起脑梗塞和神经缺失症状。以同时阻断ＣＣＡ，ＩＣＡ和ＥＣＡ造成的脑缺血性损害最重，阻断ＩＣＡ次之，阻断ＣＣＡ最轻。阻断单侧ＣＡ１小时以上，可造成脑皮层神经缺血性损害加重，若缺血时间延长可发生不可逆损害，伴有缺血性脑水肿。７６４－…     

心房纤颤致脑栓塞的临床分析

目的探讨心房纤颤（ＡＦ）致脑栓塞（ＣＥ）的临床特点和影像学改变。方法对５２例ＡＦ致ＣＥ患者的临床、ＣＴ／ＭＲＩ、治疗及转归进行分析。结果≥６０岁老年人占８２．６９％（４３／５２），且７６．７４％（３３／４３）由非瓣膜性房颤所致；栓塞性出血（ＥＨ）发生率为４０．３８％，多发生在栓塞后２周内，大面积栓塞发生ＥＨ的机率较小面积栓塞高（Ｐ＜０．００５）。结论ＡＦ是引起老年卒中的重要危险因素     

心房纤颤致脑梗塞的临床分析

目的 探讨心房纤颤（ＡＦ）致脑梗塞（ＣＥ）的临床特点和影像学改变。方法 对５２例ＡＦ致ＣＥ患者的临床、ＣＴ／ＭＲＩ，治疗及转归进行分析。结果≥６０岁老年人占８２．６９％（４３／５２），且７６．７４％（３３／４３）由非瓣膜性房颤所致；栓塞性出血（ＥＨ）发生率为４０．３８％，多发生在栓塞后２周内，大面积栓塞发生ＥＨ的机率较小面积栓塞高（Ｐ〈０．００５），结论 ＡＦ是引起老年卒中的重要危险因素。     

急性脑梗死和Alzheimer病脑脊液高水平髓鞘素抗原B细胞免 …

目的 确认急性脑梗死对髓鞘素碱性蛋白（ＭＢＰ）,髓鞘素结合糖蛋白（ＭＡＧ）和含脂质蛋白（ＰＬＰ）的Ｂ细胞免疫应答。方法 采用酶联免疫斑点技术检测了ＡＣＩ,临床可能ＡＤ和其它神经疾病（ＯＮＤ）对照组患者外周血和脑脊液（ＣＳＦ）中ＭＢＰ,ＭＡＧ和ＰＬＰ抗体分泌细胞。     

Inhibition of relapsing experimental autoimmune encephalomyelitis in SJL mice by feeding the immunodominant PLP139-151 peptide

Peripheral antigen-specific tolerance can be induced by feeding protein antigens. The mechanism has been described as either clonal anergy/deletion or induction of antigen-specific regulatory cells that produce transforming growth factor-β (TGF-β). These two mechanisms have been linked to the magnitude and frequency of the dose of antigen fed; a single high dose induces anergy/deletion, whereas multiple low doses of antigen induce TGF-β-secreting regulatory cells. In the present study, we investigated the mechanisms of feeding soluble peptides of proteolipid protein (PLP) for prevention of experimental autoimmune encephalomyelitis (EAE) induced by either intact PLP or the immunodominant PLP139-151 peptide. Feeding PLP139-151 prevented acute and relapsing EAE induced by either PLP139-151 or intact PLP. PLP139-151 feeding induced anergy in the T helper 1 (Th1) population as measured by an inhibition of both proliferation and interferon-γ (IFN-γ) production. Interleukin-4 (IL-4) production was increased, but increased TGF-β production was not observed. Importantly, PLP139-151 feeding induced anergy in peripheral and central system (CNS)-infiltrating T cells. Feeding of the subdominant PLP epitope (PLP178-191) failed to inhibit EAE induced by PLP139-151; therefore, oral tolerance was not due to induction of bystander suppression. These results demonstrate that both acute and relapsing paralysis in EAE can be prevented by feeding the immunodominant peptide of PLP. © 1996 Wiley-Liss, Inc.     

Differential recognition of peptide analogs by naive verses activated PLP 139–151-specific CD4 T cells

CD4⁺ T cells specific for PLP 139–151 induce a relapsing-remitting form of EAE which is similar to the human demyelinating disease multiple sclerosis (MS) in both clinical course and histopathology. Conservative and nonconservative amino acid substitutions were introduced at three TcR or MHC contact residues within PLP 139–151 to identify fine specificity requirements, at the polyclonal level, for stimulating naive encephalitogenic T cells and for reactivating pre-primed autoreactive T cells as measured by T cell proliferation, cytokine induction, and functional encephalitogenic potential. The results indicate that peptides with substitutions at position 145 exhibited a significantly diminished ability to induce active disease, but these substitutions had little or no effect on the ability to activate PLP 139–151-primed T cells for proliferation or disease transfer. A conservative or a nonconservative substitution at position 144 ablated both encephalitogenic potential in active and adoptive EAE models and the ability to induce proliferative responses in T cells primed to the native peptide. A nonconservative lysine for glycine, but not a conservative serine substitution, at position 146 had similar effects. In contrast to their inability to induce active EAE and stimulate in vitro proliferation of PLP 139–151-primed T cells, the Y144 and the 146 analog peptides were able to suboptimally reactivate these cells for transfer of adoptive EAE. Furthermore, the nonencephalitogenic K146 peptide was found to exacerbate in vivo induction of EAE induced by priming with a suboptimal dose of PLP 139–151. These data support the hypothesis that naive neuroantigen-specific CD4⁺ T cells have more stringent activation requirements than do PLP 139–151-specific T cells which have previously encountered antigen. The finding that the analog peptides induced differential patterns of cytokine production, with LT/TNF- production but not IFN-γ production correlating with full encephalitogenic potential, suggests different functional outcomes may result from differential levels of signal transduction triggered by the substituted peptides. The significance of these results to the potential development of autoimmune disease via molecular mimicry and for the development of new strategies for preventing and treating T cell-mediated autoimmune diseases is discussed.     

Tolerance induction by acylated peptides: suppression of EAE in the mouse with palmitoylated PLP peptides

Treatment of SJL mice either before or after challenge with palmitoylated PLP139-151 (PAL139-151) completely suppressed or considerably reduced both acute and relapsing stages of EAE induced with PLP139-151. In the presence of Pertussis toxin, treatment with PAL139-151 was less effective, but treatment with a mixture of PAL139-151 and PAL178-191, the palmitoylated PLP epitope to which T cell recognition spreads, resulted in almost complete protection. Proliferation of lymphocytes from treated mice were sharply reduced, and adoptive transfer of lymph node lymphocytes from treated mice to naive recipients resulted in the reduction of the acute phase of EAE and in delayed relapses following challenge. The results suggest that treatment with PAL139-151 leads to both anergy and the generation of regulatory cells.     

Humoral immune recognition of proteolipid protein (PLP)-specific encephalitogenic epitopes in the SJL/J mouse

SJL/J mice were immunized with human PLP as well as encephalitogenic PLP peptides 139–151 and 178–191 and the resulting antibody responses examined for immunochemical specificity employing a panel of 17 synthetic PLP peptide ligands. All animals had demonstrable circulating titers of antibodies early in the humoral immune response to their respective encephalitogens, however, there was no clear qualitative correlation between antibody responses and the induction of EAE. In the majority of PLP immunized animals, determinant-specific antibody populations, including those against encephalitogenic centers, were not detectable in the presence of an anti-PLP antibody response. Antiencephalitogenic peptide antibodies were present in both 139–151 and 178–191 immunized animals regardless of clinical/histologic status. Neither group produced cross-reactive anti PLP antibodies as detected by ELISA. In animals immunized with peptide 139–151, only anti-139–151 antibody specificities were noted. In contrast, all animals immunized with peptide 178–191 had an antibody population cross-reactive with three other PLP peptides: 97–110, 209–217, and 215–228. As humoral immune responses can be demonstrated against PLP-specific encephalitogenic epitopes, the significance of these B cell responses should be considered in the context of their potential role in the development, modulation, and/or potentiation of EAE. © 1994 Wiley-Liss, Inc.     

Lipophilin (PLP) gene in X-linked myelin disorders

There are several X-linked diseases in animals and at least one in man in which there is a failure of CNS myelination. We have recently cloned cDNAs for lipophilin (PLP) with which PLP sequences were localized to a region of the long arm of the X chromosome (Xq13-q22 in man) close to the jimpy (jp) locus in that mouse mutant. The present communication pursues the postulate that some of this class of diseases may involve mutations at the PLP locus. Blot hybridization analysis of PLP mRNA levels revealed a five-to tenfold reduction in the brains of hemizygous jp/Y mice. The major PLP mRNA species of those mice was also reduced in size. However, Southern blots of jp DNA digested with many different restriction enzymes failed to detect major deletions or other rearrangements in the PLP gene. A human PLP cDNA was isolated and employed to similarly analyze DNA from four patients diagnosed as having Pelizaeus-Merzbacher disease. In one of these four a significant rearrangement of the PLP gene was found. These findings suggest that there may be alterations in the PLP gene in both jp mouse and Pelizaeus-Merzbacher disease.     

Copolymer 1 inhibits chronic relapsing experimental allergic encephalomyelitis induced by proteolipid protein (PLP) peptides in mice and interferes with PLP-specific T cell responses

Copolymer 1 (Cop 1) is a synthetic amino acid copolymer effective in suppression of experimental allergic encephalomyelitis (EAE) and developed as a candidate drug for multiple sclerosis (MS). In the present study, we induced chronic relapsing (CR)-EAE in (SJL/J X BALB/c) F₁ mice by either whole spinal cord homogenate or two synthetic peptides of proteolipid protein (PLP), p139–151 and p178–191. When Cop 1 was added to the encephalitogenic inoculum, mice were almost completely resistant to disease induction. T cell lines to p139–151 and p178–191 were specific to these peptides. Their antigen-specific responses were inhibited by Cop I in a dose-dependent manner, while their polyclonal response to the superaniigen staphylococcal enterotoxin A (SEA) was not affected by Cop 1. Using biotinylated PLP derivatives, we demonstrated that the two PLP peptides bound to I-A' molecules, and that their binding was completely inhibited by unlabelled Cop 1. Furthermore, Cop 1 could displace the PLP peptides from the MHC binding site. These results support the potential of Cop 1 as a broad-spectrum drug for MS.     

Differential prevention of experimental autoimmune encephalomyelitis with antigen-specific DNA vaccination

We compared the potential therapeutic effect of vaccination with DNA constructs encoding two encephalitogenic proteins, PLP and MOG, on the outcome of subsequent sensitization of EAE induced in SJL/J and C57/B6 mice. Early sensitization for EAE (4 weeks after DNA vaccination) caused recipient animals to develop enhanced disease with DNA-encoding PLP but not with DNA-encoding MOG. Late sensitization (more than 10 weeks) resulted in an amelioration of EAE in animals vaccinated with both PLP and MOG DNA constructs. These results, confirming the DNA-mediated ameliorating effect on EAE, also indicate significant differences in the kinetics of development of EAE tolerance in response to vaccination with different DNA-encoding myelin antigens. Since PLP and MOG require different MHC presentation and induce different EAE models, the results point to potential differences in immune system requirements for efficient DNA-induced amelioration of the autoimmune response.     

A neuropathological analysis of experimental autoimmune encephalomyelitis with predominant brain stem and cerebellar involvement and differences between active and passive induction

Experimental autoimmune encephalomyelitis (EAE) is an autoimmune demyelinating disease that can be induced in a variety of animal species and which is commonly used as an animal model of multiple sclerosis. In rodent EAE models, the clinical disease is typified by ascending paralysis; however, other clinical patterns can also be observed by inducing disease with particular peptides of myelin proteolipid protein (PLP) or myelin oligodendrocyte glycoprotein. Here we describe EAE induced in C3H/HeJ mice by inoculation with residues 190–209 of PLP. This form of EAE is manifested clinically by a movement disorder, with axial rotation of the head and trunk. Histologically, this form of EAE is characterized by predominant cerebellar or brain stem involvement, depending on whether EAE is induced by active immunization with the PLP peptide, or by passive transfer of T cells specific for the peptide. The inflammatory cell infiltrate is composed of polymorphonuclear cells and mononuclear cells. This rotatory form of EAE may be a useful model for studying the neuropathological characteristics of multiple sclerosis affecting the brain stem and cerebellum. Received: 23 June 1999 / Revised, accepted: 25 October 1999     

Experimental allergic encephalomyelitis induced by proteolipid apoprotein in Lewis rats

Experimental allergic encephalomyelitis (EAE) was induced in inbred Lewis rats by sensitization with bovine white matter proteolipid apoprotein (PLP). 18-61 days after a single injection of 100 micrograms of PLP, 12 of 31 rats (39%) developed clinical EAE and 18 of 23 (78%) showed pathologic EAE with significant demyelination. Lymphocyte proliferative responses and antibodies to PLP were elevated but did not correlate with the clinical or pathologic state. This is the first demonstration of PLP-induced EAE with significant demyelination in rats and will contribute to the study of autoimmune demyelination.