Basic Research for Regenerative Therapy of Multiple Sclerosis

目标和背景：多发性硬化（MS）是一种免疫介导的疾病，影响中枢神经系统（CNS）白色物质，受遗传和环境因素之间复杂的相互作用调节，其特征在于引起永久性神经功能缺损的多灶性炎性脱髓鞘和轴突变性。MS显示出显著的临床病理异质性，根据病程分为复发缓解型MS（RRMS）、继发性进展型MS（SPMS）和原发性进展型MS（PPMS），根据病变分布分为常规MS（CMS）和视脊髓MS（OSMS），根据治疗反应分为干扰素-β（IFNB）应答者和无应答者，以及淋巴细胞介导的、抗体介导的、从病理学角度探讨少突胶质细胞增生介导的脱髓鞘。由于其变异性，MS的准确临床诊断往往是困难的，由于缺乏可靠的诊断标志物。近年来的研究表明，反应性胶质瘤形成的胶质瘢痕， ...更多信息 星形胶质细胞、在少突胶质细胞上表达的髓鞘相关的神经突生长抑制剂Nogo和从活化的小胶质细胞释放的促炎细胞因子在有效的髓鞘再生和轴突再生中起抑制作用。IFNB已被用作对抗MS急性复发的最有效的药物之一，尽管其潜在的机制仍然未知，并且IFNB对诱导髓鞘再生和轴突再生无效。本研究的目的是（1）通过DNA微阵列分析MS特异性基因表达谱来鉴定MS的新分子标志物;（2）建立治疗前区分IFNB应答者和非应答者的方法;（3）阐明反应性胶质增生的分子机制，（4）研究Nogo在MS轴突再生失败中的病理作用。方法、结果和结论：我们发现（1）通过DNA微阵列分析，MS患者外周血淋巴细胞中有一个参与细胞凋亡调控的基因家族异常表达。（2）通过系统聚类分析，一组在未治疗的MS患者和对照受试者之间差异表达的基因将MS患者分成四个不同的亚组，其中IFNβ应答者聚集在这些亚组中的两个中。(3)by通过免疫组织化学和蛋白质组学分析，14-3-3 β同种型与培养的人星形胶质细胞和MS病变中的反应性星形胶质细胞中的波形蛋白和GFAP结合。(4)by免疫组织化学显示，Nogo-A在存活的少突胶质细胞上上调，而Nogo受体表达在MS脱髓鞘病变中的反应性星形胶质细胞和小胶质细胞中增强。这些结果表明开发MS再生疗法的可能方法，例如靶向抑制反应性星形胶质细胞中的14-3-3功能，其可能用于预防神经胶质增生，以及阻断Nogo-A/NgR相互作用的人源化抗体的应用，这可能有助于支持MS中的轴突再生。

Objectives and Backgrounds : Multiple sclerosis(MS) is an immune-mediated disease affecting the central nervous system(CNS) white matter, regulated by a complex interplay between genetic and environmental factors, characterized by multifocal inflammatory demyelination and axonal degeneration that cause permanent neurological deficits. MS shows remarkable clinicopathological heterogeneity, categorized into relapsing-remitting MS(RRMS), secondary progressive MS(SPMS), and primary progressive MS(PPMS) based on the disease course, conventional MS(CMS) and opticospinal MS(OSMS) by lesion distribution, interferon-beta(IFNB) responder and nonresponder from the therapeutic response, and lymphocyte-mediated, antibody-mediated, and oligodendrocyte apoptosis-mediated demyelination from the pathological aspect. Because of its variability, the accurate clinical diagnosis of MS is often difficult due to lack of a reliable diagnostic marker. Recent studies showed that glial scar produced by reactive … More astrocytes, myelin-associated neurite outgrowth inhibitor Nogo expressed on oligodendrocytes, and proihflammatory cytokines released from activated microglia, play an inhibitory role in efficient remyelination and axonal regeneration. IFNB has been utilized as one of the most effective medications against acute relapse in MS, although the underlying mechanism remains unknown and IFNB is ineffective for induction of remyelination and axonal regeneration. Until present, no regenerative therapy is available for MS. The aim of this work is (1)to identify a novel molecular marker of MS by analyzing gene expression profile specific for MS on a DNA microarray, (2)to establish a method to distinguish IFNB responder and nonresponder before treatment, (3)to clarify the molecular mechanism of reactive gliosis, and (4)to investigate a pathological role of Nogo in the failure of axonal regeneration, in MS. Methods, Results, and Conclusions : We found that (1)by DNA microarray analysis, a family of genes involved in regulation of apoptosis are aberrantly expressed in peripheral blood lymphocytes in MS. (2)by hierarchial clustering analysis, a set of genes differentially expressed between untreated MS patients and control subjects separated four distinct subgroups of MS patients where IFNβ responders were clustered in two of these subgroups. (3)by immunohistochemical and proteome analysis, 14-3-3 epsilon isoform binds to vimentin and GFAP in cultured human astrocytes and reactive astrocytes in MS lesions. (4)by immunohistochemistry, Nogo-A is upregulated on surviving oligodendrocytes, while Nogo receptor expression is enhanced in reactive astrocytes and microglia in demyelinating lesions of MS. These results suggest a possible approach to develop regenerative therapy for MS, such as a targeted inhibition of 14-3-3 function in reactive astrocytes that might be useful for prevention of gliosis, and an application of humanized antibodies blocking Nogo-A/NgR interaction that might be helpful for supporting axonal regeneration in MS. Less