NEPHRITOGENIC ANTILAMININ IG--A TRANSGENIC MODEL

这里提出的研究将使用转基因的强大工具， 小鼠研究早期事件和机制，调节 产生能够介导肾损伤的自身抗体。 这 这项工作是基于对IG受体的核心作用的认识， 决定B细胞应答并参与免疫反应 细胞间和独特型的相互作用，以及有助于 自身抗体的致病潜力。 拟议的研究不断发展 从我们对肾小球免疫沉积物形成的鉴定 靶向内在肾抗原层粘连蛋白的自身抗体， 表达的可变区似乎被异常的 免疫调节 这些IG由保守的VH基因编码， 一种主要的自身免疫独特型，在抗dsDNA和 抗层粘连蛋白IG，以及能够将疾病转移至幼稚的IG 动物 此外，未突变的VH基因的反复使用表明， 这些潜在的致肾炎B细胞存在于正常的 免疫前的所有功能 这里提出的研究将检验这一假设 这些特定的疾病相关的IG受体是 免疫调节以防止它们在正常免疫环境中活化， 由于遗传性自身免疫性疾病对这些通路的干扰 易感性和/或外源性免疫刺激可导致 自身免疫 为此，免疫前库将在实验上有所偏差 通过转基因小鼠的产生。 这些将携带在他们的 生殖系功能性重排基因，使得大多数B 细胞表达预定的抗自身特异性， 潜力 有了这个工具，这些特定的病原体之间的相互作用 整个生物体的复杂免疫网络中的决定因素 可以检查。 B细胞增殖的体内和体外测定， 分化和抗原结合以及单克隆IG技术将是 用于比较发育命运，免疫状态， 自身反应性的表达和致病性 在不同生物学相关性下产生的B细胞和IG 条件 1)在正常的免疫环境中， 非自身免疫性C57 BL/6小鼠; 2）在MRL/lpr的影响下 自身免疫背景; 3）在外源性抗原的影响下， (DNA和层粘连蛋白）和非特异性（LPS）免疫刺激。 初始 研究将确定是否以及如何在正常情况下避免自身免疫。 主持人 这将为评价操作提供背景 旨在改变疾病的表达。 最终，我们希望 使用靶向内在肾抗原的IG的自身免疫模型。 这些结果将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.