CB2 Receptor Regulatin of Inflammatory Response in EAE

描述(申请人提供)：多发性硬化症(MS)是一种慢性中枢神经系统脱髓鞘疾病，在西方国家是导致神经功能障碍的主要原因。尽管进行了密集和持续的研究工作，但现有的治疗方案并不能实质上预防组织损伤和临床残疾。MS是一种自身免疫性神经退行性疾病，由中枢神经系统炎症发作所致。我们建议研究一种新合成的分子(O-1966)，它可能显著降低免疫细胞对中枢神经系统损伤的贡献。O-1966是大麻类分子中的一员。虽然从大麻植物中提取的大麻素已经被使用了数千年，但它们在治疗多发性硬化症等疾病方面的价值受到其精神活性的限制。目前，靶向CB2受体是可能的，主要表达在免疫细胞上，具有免疫调节功能。O-1966是一种选择性的CB2激动剂，可以改变免疫功能，而不会对精神产生影响。初步结果表明，刺激CB2受体可减轻实验性自身免疫性脑脊髓炎(EAE)的中枢神经系统损伤。我们的初步数据表明，O-1966在EAE中的保护作用是通过对炎症的影响而实现的。在这项建议中，我们将研究O-1966具体影响免疫细胞功能的分子机制。拟议的研究将在分子/细胞和整个动物水平上进行，以便更好地评估O-1966的治疗潜力。我们认为，选择性CB2R激动剂O-1966激活CB2受体的结果是：1.通过诱导调节性T细胞改变效应T细胞的表型；2.通过减少T细胞的滚动和与血管CNS内皮的黏附而抑制脑源性T细胞向中枢神经系统的运输。在具体目标1中，我们将评估O-1966在EAE中的作用，并基于CB2激活导致T细胞分化从脑源性Th17/Th1向调节性T细胞转变的假设，鉴定CNS浸润性细胞。根据初步研究，我们认为CB2选择性激动剂O-1966通过诱导产生耐受性树突状细胞来影响T细胞分化。这是一个新的研究领域，因为大麻素在DC分化中的作用尚未得到解决。在特定的目的2中，我们将在活体显微镜下观察O-1966对脑源性T细胞和Treg细胞滚动和与CNS毛细血管后小静脉黏附的影响，它对Tef/Treg细胞和CNS内皮细胞黏附分子表达的影响，以及对参与活化T细胞向血管周围空间和CNS实质募集的趋化因子表达的影响。识别CB2受体配体的分子/细胞因子及其抗炎作用机制，对认识和干预中枢神经系统自身免疫性/炎症性疾病具有重要意义。这项提案的最终目标是开发新的有效治疗剂，旨在改变导致多发性硬化症的炎症反应，这与公共卫生密切相关：多发性硬化症是最常见的中枢神经系统慢性脱髓鞘疾病，是西方国家残疾的主要原因。全世界约有250万人患有多发性硬化症，美国有40万人患有多发性硬化症。除了对多发性硬化症患者的生活质量造成破坏性影响外，对个人和国家层面的经济影响都是巨大的。据估计，每年治疗多发性硬化症的费用超过25亿美元。尽管进行了密集和持续的研究工作，但现有的治疗方案并不能实质上预防组织损伤和临床残疾。目前提案的最终目标是开发治疗多发性硬化症的新的有效治疗剂。

DESCRIPTION (provided by applicant): Multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system, is a major cause of neurological disability in Western countries. In spite of intensive and sustained research efforts, existing treatment options do not substantially prevent tissue damage and clinical disability. MS is increasingly recognized as an autoimmune neurodegenerative disease triggered by inflammatory attacks of the CNS. We propose to study a newly synthesized molecule (O-1966) that may significantly reduce the contribution of immune cells to CNS damage. O-1966 is a member of the cannabinoid class of molecules. While cannabinoids derived from the plant Cannabis Sativa have been used for thousands of years, their value in the treatment of diseases such as MS has been limited by their psychoactive properties. Presently, it is possible to target the CB2 receptors, primarily expressed on immune cells, which exhibit immunomodulatory functions. O-1966, a selective CB2 agonist, alters immune functions without psychoactive effects. Preliminary results showed that stimulation of CB2 receptors decreases CNS damage in experimental autoimmune encephalomyelitis (EAE). Our preliminary data suggest that the protective action of O-1966 in EAE occurs through effects on inflammation. In this proposal we will investigate the molecular mechanisms by which O-1966 specifically influences the function of immune cells. The proposed studies will be conducted at both molecular/cellular and whole animal level, to allow a better evaluation of the therapeutic potential of O- 1966. We propose that CB2 receptor activation by the selective CB2R agonist O-1966 results in: 1. changes in the phenotype of effector T cells through the induction of regulatory T cells; and 2. inhibition of encephalitogenic T cell traffic to the CNS through a reduction in T cell rolling and adhesion to the vascular CNS endothelium. In Specific Aim 1 we will evaluate the effect of O-1966 in EAE and characterize the CNS infiltrating cells, based on the hypothesis that CB2 activation results in a shift in T cell differentiation from encephalitogenic Th17/Th1 to regulatory T cells. Based on preliminary studies, we propose that the CB2 selective agonist O-1966 affects T cell differentiation through the induction of tolerogenic dendritic cells. This represents a new research area, since the role of cannabinoids on DC differentiation has not been addressed. In Specific Aim 2 we will examine the effects of O-1966 on encephalitogenic Teffector and Treg cell rolling and adhesion to CNS postcapillary venules by intravital microscopy, its effect on the expression of adhesion molecules in Teff/Treg cells and in CNS endothelial cells, and on the expression of chemokines involved in the recruitment of activated T cells to the perivascular space and CNS parenchyma. The identification of molecular/cellular factors and of the mechanisms involved in the anti-inflammatory effect of CB2 receptor ligands will have a significant impact on the understanding and intervention in CNS autoimmune/inflammatory diseases. The ultimate goal of this proposal is the development of new effective therapeutic agents targeted at modification of the inflammatory responses that contribute to MS. PUBLIC HEALTH RELEVANCE: Multiple sclerosis, the most common chronic demyelinating disease of the central nervous system, is a major cause of disability in Western countries. Approximately 2.5 million people worldwide and 400,000 Americans suffer from MS. In addition to the often devastating consequences for quality of life for individuals suffering from MS, the economic impact at both the personal and national level is substantial. It is estimated that the annual costs for the treatment of MS is in excess of $2.5 billion. In spite of intensive and sustained research efforts, existing treatment options do not substantially prevent tissue damage and clinical disability. The ultimate goal of the current proposal is the development of new effective therapeutic agents for the treatment of MS.