ANTI-SM B CELLS OF MRL/LPR MICE

本提案的长期目标是了解B中的事件 细胞发育和选择，导致生产 MRL/Mp-lpr/lpr（MRL/lpr）小鼠中的自身抗体。本品系小鼠 患上类似系统性狼疮的自发性自身免疫性疾病 红斑性狼疮（SLE）。我们已经开始研究B细胞对 Sm颗粒，一种存在于所有细胞核中的核糖核蛋白。的 人类对该颗粒的自发反应是SLE的诊断， MRL/lpr小鼠是唯一一种自发发展成 对这种抗原的反应。对Sm的反应与SLE的相关性 表明了疾病的病因学与 这些自身抗体的产生。我们之前的分析表明 Sm特异性B细胞是通过DNA选择的，但也表明 第二种抗原的参与，可能是Sm。我们在目标1中建议， 检验Sm是这种应答中的选择性抗原的假设。这 将通过鉴定多个抗Sm抗体中的突变来完成 杂交瘤，并确定它们的分布是否有偏差， 突变型B细胞抗原选择指示。另外通过 使用转染瘤抗体，我们将确定观察到的 突变改善Sm和DNA结合。在目标2中，我们将研究 对于抗Sm选择的杂交瘤的双重Sm和DNA结合。我们提出 DNA结合主要由H链决定，Sm 结合主要由L链决定。这一假设将是 通过测量产生的转染瘤的Sm和DNA结合来测试 在VH或Vk中不同的抗体。在目标3中，我们将生成 使用抗Sm和抗Sm/DNA的VH和Vk基因的转基因小鼠 杂交瘤 将转基因小鼠与正常和 自身免疫遗传背景，以检查这些免疫调节 正常小鼠中的细胞和自身免疫小鼠中的失调。

The long term objective of this proposal is to understand the events in B cell development and selection that lead to the production of autoantibodies in MRL/Mp-lpr/lpr (MRL/lpr) mice. Mice of this strain develop a spontaneous autoimmune disease that resembles systemic lupus erythematosus (SLE). We have begun a study of the B cell response to the Sm particle, a ribonucleoprotein present in the nuclei of all cells. The spontaneous response to this particle in humans is diagnostic of SLE, and MRL/lpr mice are the only mouse model that spontaneously develops a response to this antigen. The correlation of the response to Sm and SLE suggests an essential relationship between the etiology of the disease and the production of these autoantibodies. Our previous analysis indicates that Sm-specific B cells are selected by DNA, but also indicates the involvement of a second antigen, presumably Sm. We propose in Aim 1 to test the hypothesis that Sm is a selecting antigen in this response. This will be accomplished by identifying the mutations in multiple anti-Sm hybridomas, and determining whether their distribution is biased, an indication of antigen selection of mutant B cells. In addition, through the use of transfectoma antibodies we will determine whether the observed mutations improve Sm and DNA binding. In Aim 2 we will examine the basis for the dual Sm and DNA binding of anti-Sm selected hybridomas. We propose that DNA binding is determined principally by the H chain and that Sm binding is determined principally by the L chain. This hypothesis will be tested by measuring Sm and DNA binding of generated transfectomas antibodies that differ in the VH or Vk. In Aim 3 we will generate transgenic mice using VH and Vk genes of anti-Sm and anti-Sm/DNA hybridomas. Transgenic mice will be crossed onto both normal and autoimmune genetic backgrounds to examine the immunoregulation of these cells in normal mice and their disregulation in autoimmune mice.