B cell regulation of diabetogenic activity

描述(由申请人提供)：为什么曲谱库的特定组成部分发展或未能发展是一个复杂的问题，与在不同水平上决定免疫优势的力量有关。NOD小鼠有产生自身免疫谱并死于1型糖尿病(T1D)的倾向。然而，有多种方法可以很容易地纠正Nod的问题。我们想要探索其中一些调节疾病过程的途径，并涉及B细胞效应，这些效应特定地影响T细胞库的组成。首先，在整个糖尿病前期和糖尿病期间，通过使用CDR3长度谱，并在出现“特征峰”(SP)之后，将跟踪在NOD中自发出现的特定流行克隆型的不同的一组，每个峰反映BV/BJ基因家族内3000个可能的CDR3长度峰之一。问题是，公共克隆类型的出现是否有明确的、程序化的、随机的或同时出现的顺序。然后将研究B细胞充足的NOD小鼠和B细胞缺乏的NOD小鼠之间的SPS的差异。将寻求CD4和CDS克隆外观的重合，询问它是否依赖于它们的特定决定因素的接近。有了克隆生活史的知识，我们将探讨两个令人烦恼的问题。有数据强调B细胞作为抗原提呈细胞在NOD中征募致病T细胞的重要性：在B细胞基因敲除的小鼠中，不会发生糖尿病，也不能做出某些相关的抗原特异性反应。这表明B细胞和T细胞识别的决定簇之间的关系非常严格，而且树突状细胞和巨噬细胞不能产生某些抗原决定簇。我们将重建具有不同B细胞群体的B基因敲除小鼠，试图学习对特定B细胞的严格要求的规则。是否激活的B细胞比未激活的B细胞更有效，可以通过转基因B细胞来发现。使用环磷酰胺，移除或灭活调节细胞，将有可能确定特定的SP为调节细胞，通过在药物治疗的小鼠中跟踪它们的消失。或者，可能会披露对监管特别敏感的某些主要SP。将进行B细胞Ag-LG构建物激活抗原特异性T细胞的研究。我们将彻底测试的保护机制是由充当APC的B细胞内的MHC分子捕获决定簇，并将使用包含捕获决定簇和要捕获的决定簇在同一肽链或基因片段上的嵌合肽。

DESCRIPTION (provided by applicant): Why particular components of the repertoire develop or fail to develop is a complex problem related to the forces that determine immunodominance at various levels. The NOD mouse has a propensity for generating an autoimmune repertoire and succumbing to Type 1 diabetes (T1D). Nevertheless, there are a variety of ways that the NOD's problems can be readily corrected. We would like to explore some of these pathways that modulate the disease process and involve B cell effects that specifically affect the composition of the T cell repertoire. First, a distinct panel of certain prevalent clonotypes that arise spontaneously in the NOD will be followed throughout the prediabetic and diabetic periods, by using CDR3-length spectroscopy, and following the appearance of "signature peaks" (SPs), each reflecting one of the 3000 possible peaks of CDR3 lengths within BV/BJ gene families. The question of whether there is a clear programmed or random or a simultaneous order of appearance of public clonotypes will be asked. The difference in SPs between NOD mice in B cell sufficient and B cell deficient mice will then be studied. The coincidence of CD4 and CDS clonal appearance will be sought, asking whether it is dependent on the proximity of their specific determinants. With the knowledge of the clonotypic life histories, we will approach two vexing problems. There are data emphasizing the importance of the B cell as an antigen presenting cell in enlisting disease- causing T cells in the NOD: in a B cell knockout mouse, diabetes does not occur, nor can certain relevant Ag-specific responses be made. This suggests that there are great stringencies in the relationships between determinants recognized by the B cell and T cell, and also, that dendritic cells and macrophages cannot generate certain antigenic determinants. We will reconstitute B knockout mice with different populations of B cells to attempt to learn the rules for the stringent requirement for particular B cells. Whether activated B cells are more effective than naive B cells can be discovered with transgenic B cells. Using cyclophosphamide, which removes or inactivates regulatory cells, it will be possible to identify particular SPs as regulatory cells, by following their disappearance in drug-treated mice. Alternatively, certain dominant SPs may be disclosed which are particularly sensitive to regulation. Studies of activation of antigen-specific T cells with B cell Ag-lg constructs will be performed. The mechanism of protection that we will test thoroughly is determinant capture by MHC molecules within B cells acting as APC, and chimeric peptides will be employed that contain the capturing determinant and the determinant to be captured on the same peptide chain or gene segment.