ANTIBODIES THAT PLAY DIFFERENT ROLES IN MYASTHENIA GRAVI

这项研究计划涉及自身抗体的特征。 与肌肉乙酰胆碱受体(AChR)的反应性 导致神经肌肉疾病，重症肌无力(MG)。过去时 观察表明，在两个国家的 MG患者产生的循环抗AChR抗体及其严重程度 由此产生的疾病症状。因此，这样做的目的是 调查是为了证明个别物种之间的差异。 由个别患者产生的抗AChR抗体可能会 将抗体分类为与1相关的子集) 抗原结合的特殊模式精细特异性(包括 与主要免疫原区(MIR)的反应性和有趣的 过去注意到的交叉反应(即AChR和肌球蛋白之间)，以及 2)具有高或低的致病潜力。要使用的策略 是将抗原结合的精细特异性的测定与 基于等电点的抗体分析与纯化 (即制备性等电聚焦)。通过这种方式，关系可以 在与AChR和AChR的特定反应模式之间揭示 “克隆型”B细胞产物(即抗AChR抗体)。这应该是 允许以不同于过去的视角看待这种关系 在分离的MG血清中发现多克隆抗体的研究。 因此，该项目将根据以下几个方面解决具体目标 患者抗体结合和纯化的标准如下。 此外，还将寻找特定子集之间的关系 抗体和它们的结合特异性，与它们的能力 影响AChR的表达及其致病潜能。 特定目标1.确定反应性分布和潜力 涉及抗-克隆性种的免疫病理关系 AchR抗体。将使用分析性IEF来评估反应性和 抗AChR抗体与MIR-R的交叉反应谱 相关多肽和肌球蛋白，以及与11E10的关联 独特型。制备性IEF(PIEF)将用于纯化克隆型 用于结合特异性测试的限制性抗AChR抗体， 受体交联性/下调活性，并用于测试 通过被动抗体转移研究致病潜力 免疫幼稚的老鼠。 特异性目的2.确定血清学和潜在的免疫病理学 抗AChR抗体克隆型与 MLR相关合成肽的特异性。抗体是针对 通过吸附和洗脱进行亲和纯化的研究 来自Alpha61-76 MLR相关肽所在的Sepharose柱 已经联系在一起了。对这些抗原特异性抗体的评估将是 类似于为具体目标1所描述的内容。 特异目的3.确定血清学和潜在的免疫病理学 涉及抗AChR抗体克隆型物种的关系 缺乏与MIR相关的合成肽的特异性。为了 进一步阐明猪传染性支气管炎的血清学和免疫病理学重要性 对MIR有反应性的抗体，患者Ig已耗尽 与α61-76 MLR相关多肽的反应性将是 检查过了。对这些抗原特异性抗体的评估将是 类似于为具体目标1所描述的内容。

This research proposal involves the characterization of autoantibodies with reactivity for the muscle receptor for acetylcholine (AChR) responsible for the neuromuscular disorder, myasthenia gravis (MG). Past observations indicate a frequent disparity between the level of circulating anti-AChR antibodies produced in MG patients and the severity of resulting disease symptoms. Therefore, the objective of this investigation is to demonstrate distinctions among the individual species of anti-AChR antibodies produced by individual patients that might allow the categorization of antibodies into subsets associated with 1) particular patterns of antigen binding fine-specificity (including reactivity with the main immunogenic region (MIR) and the intriguing crossreactivities noted in the past (i.e., between AChR and myosin]), and 2) with high or low disease-causing potential. The strategy to be used is to combine determinations of antigen binding fine-specificity with the analysis and purification of antibodies based on their isoelectric point (i.e., preparative isoelectric focusing). In this way, relationships may be revealed between particular patterns of reactivity with the AChR and "clonotypic" B cell products (i.e., anti-AChR antibodies). This should allow a different perspective on such relationships than have past studies of the polyclonal antibodies found in unfractionated MG sera. Accordingly, this project will address specific aims based on several criteria of patient antibody binding and purification described below. Additionally, relationships will be sought between particular sub sets of anti body and their binding specificity, with their ability to influence the expression of AChR and their disease-causing potential. SPECIFIC AIM 1. Determine the reactivity profile and potential immunopathological relationships involving -clonotypic species of anti- AChR antibodies. Analytical IEF will be used to assess the reactivity and crossreactivity profiles of anti-AChR antibodies with respect to the MIR- associated peptide and myosin, as well as for associations with the 11E10 idiotype. Preparative IEF (pIEF) will be used to purify clonotypically restricted anti-AChR antibodies for tests of binding specificity, receptor crosslinking/down-modulating activities, and for tests of disease-causing potential via passive antibody transfer studies into immunologically naive rats. SPECIFIC AIM 2. Determine serological and potential immunopathological relationships involving clonotypic species of anti-AChR antibodies with specificity for an MlR-associated synthetic peptide. Antibodies are to be studied that have been affinity-purified by adsorption to and elution from Sepharose columns to which the alpha61-76 MlR-associated peptide has been attached. Evaluations of these antigen-specific antibodies will be similar to those described for Specific Aim 1. SPECIFIC AIM 3. Determine serological and potential immunopathological relationships involving clonotypic species of anti-AChR antibodies that lack specificity for an MIR-associated synthetic peptide. In order to further clarify the serological and immunopathological importance of antibodies with reactivity to the MIR, patient Ig that has been depleted of reactivity with the alpha61-76 MlR-associated peptide will be examined. Evaluations of these antigen-specific antibodies will be similar to those described for Specific Aim 1.