B LYMPHOCYTE TOLERANCE IN HEALTH AND AUTOIMMUNITY

申请人申请研究项目补助金(RO1)，以澄清 B淋巴细胞耐受的机制。该项目的长期目标 是为了了解自体特异性B细胞是如何被控制的，以确定 如果有自身免疫倾向的小鼠品系具有固有的B细胞耐受性 缺陷，如果是这样的话，定位涉及的基因。 作为本研究的基础，转基因小鼠进行了功能重排 已产生抗H-2Kk IgM/IGD抗体基因。在这些小鼠中，B- 在适当的I类抗原存在的情况下，细胞是耐受的。 这项建议的具体目标如下： 1.确定自体耐受的外周耐受机制 B细胞。我们将跟进我们在最初拨款中获得的结果。 对外周表达抗原的耐受性进行分析。去做 我们将分析对非膜自身抗原的耐受性 在骨髓中表达，在成年小鼠的骨髓中发育B细胞， 但在其他器官中发现的细胞表面，如肝脏， 皮肤和胰腺。在本分析中，我们将利用现有的 由其他人生产的转基因小鼠，目标是表达 低亲和力的Kb与这些外周组织结合。这种方法行得通。 因为转基因编码的抗体水平很低，但是 对KB抗原具有重要的生理亲和力。 2.确定自身免疫易感遗传背景对 自身对外周膜抗原的耐受性。我们已经这么做了 证实在至少一个表达KB的转基因株系中 外周自身特异的抗H-2K B细胞可通过缺失耐受。我们 会将这些转基因基因转移到具有自身免疫倾向的小鼠品系上 确定它们是否表现出对KB抗原的B细胞耐受缺陷 这个双转基因系统。 3.开始MRL株背景基因的染色体定位 小鼠似乎倾向于打破B细胞的自我耐受性 MRL/LPR/3-83转基因回交小鼠。我们将使用最现代的 经典遗传作图中的技术，包括利用 多态DNA微卫星聚合酶链式反应标记。在……里面 在这个过程中，我们将确定转基因系统是否提供 对影响基因图谱的速度和准确性的优势 自身免疫力。

The applicant seeks a research project grant (RO1) to elucidate the mechanisms of B lymphocyte tolerance. The long-term goal of the project is to understand how autospecific B-cells are controlled, to determine if autoimmune-prone mouse strains have intrinsic B-cell tolerance defects, and, if so, to localize the genes involved. As a basis for this study, mice transgenic for functionally rearranged anti-H-2Kk IgM/IgD antibody genes have been generated. In these mice B- cells are tolerized in the presence of the appropriate class I antigens. The Specific Aims of this proposal are as follows: 1. To determine the mechanisms of peripheral tolerance in autospecific B-cells. We will follow up the results we obtained in our initial grant with the analysis of tolerance to peripherally-expressed antigen. To do this we will analyze tolerance to membrane autoantigen that is not expressed in the bone marrow, where B-cells develop in the adult mouse, but on the surfaces of cells found in other organs, such as the liver, skin and pancreas. In this analysis we will take advantage of existing transgenic mice, produced by others, that target the expression of the low affinity ligand Kb to these peripheral tissues. This approach works because the antibody encoded by the transgenes has a low, but physiologically significant affinity for the Kb antigen. 2. To determine the influence of autoimmune-prone genetic background on self-tolerance to peripheral membrane antigen. We have already established that in at least one transgenic line expressing Kb in the periphery, autospecific anti-H-2K B-cells are tolerized by deletion. We will cross these transgenes onto autoimmune-prone strains of mice to determine if they manifest a B-cell tolerance defect to Kb antigen in this double transgenic system. 3. To begin the chromosomal mapping of a background gene of MRL strain mice that appears to favor the breaking of self-tolerance in the B-cells of MRL/lpr/3-83 transgenic backcross mice. We will use the most modern technique in classical genetic mapping, including taking advantage of polymorphic DNA microsatellite polymerase chain reaction markers. In this process we will determine if the transgenic system provides advantages of speed and accuracy to the mapping of genes that affect autoimmunity.