Immune Dysregulation During Multiple Sclerosis Relapse

项目总结/摘要 多发性硬化症（MS）是一种中枢神经系统的炎性脱髓鞘疾病， 超过40万人。MS最常见的临床形式表现为复发-缓解型 临床病程（RRMS）。然而，RRMS患者和非RRMS患者之间存在几种免疫差异， 对于健康受试者，临床复发的免疫学基础仍然知之甚少。一些研究 在急性髓磷脂病中显示出对髓鞘抗原的异常免疫应答以及调节性T和B细胞的缺陷。 疾病复发。然而，复发的免疫失调仍然不清楚。特别是， 缺乏针对CD 4和CD 8 T细胞效应和调节应答的纵向研究 在急性复发之前、期间和之后。利用创新的方法，我们最近的研究已经取得了 几个有趣的观察结果与急性复发期间的CD 4和CD 8调节性T细胞生物学有关 我们已经证明了CNS特异性CD 8 + T细胞的新的和意想不到的免疫调节功能， 细胞有趣的是，静止期疾病的RRMS患者和健康受试者显示出相当的水平， CNS特异性CD 8抑制剂活性。然而，在急性复发期间，患者表现出戏剧性的 CNS特异性抑制活性的缺陷，即使可以检测到CNS特异性CD 8应答 在复发前的水平。此外，随着患者[通过各种不同的疗法]达到疾病静止， 它们一致地显示CNS特异性CD 8抑制活性的正常化。我们进一步观察到 这些缺陷是可以通过调节细胞因子环境和通过理解细胞因子的作用来纠正的。 通过这些机制实现免疫调节。在最近未发表的研究中，我们还 显示在急性MS期间诱导的CD 4+调节性T细胞的新亚群的失调 复发基于这些发现，我们假设，免疫系统的累积性纵向缺陷， 调节功能和效应物抗性导致MS复发。作为推论，我们预测， 纠正这些功能缺陷是疾病静止期的重要免疫学相关性。通过 我们将通过描述CD 4和CD 8的纵向波动来解决这些假设 调节能力及其与MS复发的关系。我们将剖析复发的各种机制- 相关的CD 8调节缺陷，并试图设计策略，以纠正观察到的缺陷。的 拟议中的研究将为疾病的免疫过程提供更基本的见解 复发与新的免疫策略的潜力。

Project Summary/Abstract Multiple sclerosis (MS) is an inflammatory, demyelinating disorder of the central nervous system that affects over 400,000 people in the US. The most common clinical form of MS presents with a relapsing-remitting clinical course (RRMS). Whereas several immune differences have been shown between RRMS patients and healthy subjects, the immunologic basis of a clinical relapse remains poorly understood. Some studies have shown aberrant immune responses to myelin antigens and defect in regulatory T and B cells during an acute disease relapse. However, the immune dysregulation that underlies the relapse remains unclear. In particular, there is a paucity of longitudinal studies addressing CD4 and CD8 T cell effector and regulatory responses before, during and after an acute relapse. Using innovative approaches, our recent studies have made several interesting observations relating to CD4 and CD8 regulatory T cell biology during acute relapse of MS. We have demonstrated the novel and unexpected immune regulatory function of CNS-specific CD8+ T cells. Interestingly, RRMS patients with quiescent disease and healthy subjects showed comparable levels of CNS-specific CD8 suppressor activity. However, patients during an acute relapse showed a dramatic deficit of CNS-specific suppressor activity, even when CNS-specific CD8 responses could be detected at pre-relapse level. Moreover, as patients attained disease quiescence [with various different therapies], they consistently showed normalization of CNS-specific CD8 suppressor activity. We have further observed that these deficits are correctable by modulation of the cytokine milieu and through understanding of the mechanisms through which immune regulation is achieved. In recent unpublished studies, we have also shown the dysregulation of a novel sub-population of induced CD4+ regulatory T cells during an acute MS relapse. Based on these findings, we hypothesize that an accumulating longitudinal deficit of immune regulatory function and effector resistance results in an MS relapse. As a corollary, we predict that correcting these functional deficits is an important immunologic correlate of disease quiescence. Through the proposed studies, we will address these hypotheses by delineating the longitudinal fluctuation of CD4 and CD8 regulatory ability and its relationship with an MS relapse. We will dissect the various mechanisms of relapse- associated CD8 regulatory deficit and attempt to devise strategies to correct the observed deficits. The proposed studies will provide greater fundamental insights into the immunologic processes underlying disease relapse with the potential for novel immunotherapeutic strategies.