NEPHRITOGENIC ANTILAMININ IG--A TRANSGENIC MODEL

本文提出的研究将使用转基因这一强大的工具 鼠标来检查早期事件和调节 产生能够调节肾脏损害的自身抗体。这 这项工作是基于对免疫球蛋白受体在 测定B细胞应答并参与免疫学 细胞间和独特型的相互作用，以及有助于 自身抗体的致病潜能。拟议中的研究进展 从我们对肾小球免疫沉积形成的鉴定 针对固有肾脏抗原的自身抗体，层粘连蛋白，以及 表达似乎是异常靶标的可变区 免疫调节。这些免疫球蛋白由保守的VH基因编码，这些基因定义了 一种主要的自身免疫独特型，经常在抗dsDNA和 抗层粘连蛋白Ig，以及能够将疾病传播给幼稚的Ig 动物。此外，未突变的VH基因的反复使用表明 正常人群中这些潜在的肾炎性B细胞的存在 免疫前曲目。这里提出的研究将检验这一假设 这些特定的疾病相关免疫球蛋白受体是 免疫调节以防止它们在正常的免疫环境中被激活， 而这些通路的扰动是由于遗传的自身免疫 易感性和/或外源性免疫刺激可导致 自身免疫力。 为此，前免疫曲目将在实验上有所偏颇 通过产生转基因小鼠。这些将携带在他们的 生殖系对基因进行了功能重排，使大多数B 细胞表达预先确定的抗自身特异性与致病性 潜力。有了这个工具，这些特定致病原之间的相互作用 整个生物体复杂的免疫网络中的决定因素 可以被检查。体内和体外B细胞增殖试验， 分化抗原结合和单抗Ig技术将 用来比较免疫学的发育命运、状态 枯草杆菌的能力、自身反应性和致病性的表达 在不同生物相关性下产生的B细胞和Ig 条件。1)在正常的免疫环境中 非自身免疫性C57BL/6小鼠；2)受MRL/LPR的影响 自身免疫背景；3)外源性抗原的影响 (DNA和层粘连蛋白)和非特异性(内毒素)免疫刺激。首字母 研究将确定在正常情况下是否以及如何避免自身免疫 主持人。这将为评估操纵提供一个背景 旨在改变疾病的表现。最终，我们希望产生 一种使用免疫球蛋白的自身免疫模型，以一种固有的肾脏抗原为靶标。 这一结果应该有助于我们理解免疫学 导致自身免疫性肾病和全身性疾病的调节失调 自身免疫，并最终有助于发展新的 干预措施。

The research proposed here will use the powerful tool of the transgenic mouse to examine the early events and mechanisms that regulate the production of autoantibodies capable of mediating renal damage. This work is based on recognition of the central role of the Ig receptor in determining B cell responses and participating in immunologic intercellular and idiotypic interactions, as well as contributing to the pathogenic potential of autoantibodies. The proposed studies evolved from our identification of glomerular immune-deposit forming autoantibodies that target the intrinsic renal antigen, laminin, and that express variable regions that appear to be targeted by abnormal immunoregulation. These Ig are encoded by conserved VH genes that define a major autoimmune idiotype and recur frequently among anti-dsDNA and anti-laminin Ig, and among Ig capable of transferring disease to naive animals. Furthermore, the recurrent use of unmutated VH genes suggests the presence of these potentially nephritogenic B cells within the normal preimmune repertoire. The studies proposed here will test the hypothesis that these specific disease-associated Ig receptors are targets of immunoregulation to prevent their activation in the normal immune milieu, and that perturbation of these pathways due to a genetic autoimmune predisposition and/or exogenous immunostimulation can lead to autoimmunity. For this purpose, the preimmune repertoire will be experimentally biased through the generation of transgenic mice. These will carry in their germlines functionally rearranged genes such that the majority of the B cells express predetermined anti-self specificities with pathogenic potential. With this tool, the interactions of these specific pathogenic determinants within the complex immunologic network of the whole organism can be examined. In vivo and in vitro assays of B cell proliferation, differentiation and antigen binding and monoclonal Ig technology will be employed to compare the developmental fate, state of immunologic competence, expression of autoreactivity and pathogenicity of the resulting B cells and Ig under different biologically relevant conditions. 1) within the context of the normal immunologic milieu of nonautoimmune C57BL/6 mice; 2) under the influence of the MRL/lpr autoimmune background; and 3) under the influence of exogenous antigenic (DNA and laminin) and nonspecific (LPS) immunostimulation. Initial studies will determine if and how autoimmunity is avoided in the normal host. This will provide a background for evaluation of manipulations designed to alter disease expression. Ultimately, we hope to generate a model of autoimmunity using Ig that target an intrinsic renal antigen. The results should contribute to our understanding of the immunologic dysregulation that leads to autoimmune renal disease and systemic autoimmunity, and ultimately contribute to the development of new interventions.