Cr2 as a Murine Lupus Susceptibility Gene

Cr2 作为小鼠狼疮易感基因

• 批准号: 6680934
• 负责人: SUSAN A. BOACKLE
• 金额: $ 9.69万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6680934
• 关键词: B lymphocyte; SDS polyacrylamide gel electrophoresis; autoimmunity; cell line; complement receptor; disease /disorder model; enzyme linked immunosorbent assay; flow cytometry; gene expression; gene targeting; genetic polymorphism; genetic regulation; genetic susceptibility; genetically modified animals; immunoprecipitation; laboratory mouse; polymerase chain reaction; site directed mutagenesis; systemic lupus erythematosus

DESCRIPTION (provided by applicant): The major murine systemic lupus erythematosus (SLE) susceptibility locus, Sle1, corresponds to 3 loci independently affecting loss of tolerance to chromatin in the NZM2410 mouse. The congenic interval corresponding to Sle1c, derived from NZW, contains Cr2, which encodes complement receptors I and 2 (CR1/CR2, CD35/CD21). CR1/CR2 deficiency has been associated with autoimmune disease in both humans and in animal models. A structural difference in a critical ligand-binding domain has recently been identified in Sle1c CR1/CR2 which results in significant impairment in receptor function. These results strongly support the role of Cr2 as a disease susceptibility gene in the Sle1c interval. The project outlined in this proposal will be directed towards characterizing the role of NZW CR2 in the NZM2410 mouse model for lupus. The specific aims are to prove that CR2 is the lupus susceptibility gene in the NZM2410 Sle1c interval, to identify the structural domains in NZW CR2 that are critical in loss of tolerance, and to determine the mechanisms by which NZW CR2 results in loss of tolerance. Proof that CR2 is the lupus susceptibility gene in the Sle1c locus will be provided by demonstrating that the Sle1c phenotypes resolve in the presence of normal gene products. Recombinant strains that contain narrowed intervals containing Cr2 will be assessed to ensure that CR2 dysfunction continues to track with autoimmune disease, The critical receptor domains that result in the autoimmune phenotypes will be determined, using both CR2-deficient cell lines transfected with recombinant proteins as well as B cells from BAC transgenic mice that express various forms of the polymorphic NZW CR2. Finally, the mechanisms by which the altered NZW CR2 allele results in loss of B cell tolerance will be characterized using the 3-83 and HEL models for B cell tolerance. These studies will clarify the specific functions of CR2, impaired in the NZM2410 mouse model, that may impact on the development of autoimmune disease and thus be important targets for therapeutic interventions.

描述（由申请方提供）：主要鼠系统性红斑狼疮（SLE）易感基因座Sle 1对应于独立影响NZM 2410小鼠染色质耐受性丧失的3个基因座。与Sle 1c对应的同源间隔来自NZW，含有编码补体受体I和2（CR 1/CR2，CD 35/CD 21）的Cr2。CR 1/CR2缺陷与人类和动物模型中的自身免疫性疾病相关。最近在Sle 1c CR 1/CR2中发现了一个关键配体结合结构域的结构差异，导致受体功能显著受损。这些结果强烈支持的作用，Cr2作为一种疾病的易感基因在Sle 1c间隔。本提案中概述的项目将致力于表征NZW CR 2在狼疮NZM 2410小鼠模型中的作用。具体目的是证明CR2是NZM 2410 Sle 1c区间的狼疮易感基因，以确定NZW CR2中对耐受性丧失至关重要的结构域，并确定NZW CR2导致耐受性丧失的机制。通过证明Sle 1c表型在存在正常基因产物的情况下消退，将提供CR2是Sle 1c基因座中狼疮易感基因的证据。将评估包含含Cr2的窄间隔的重组菌株，以确保CR2功能障碍继续跟踪自身免疫性疾病。将使用用重组蛋白转染的CR2缺陷细胞系以及来自表达各种形式的多态性NZW CR2的BAC转基因小鼠的B细胞来确定导致自身免疫表型的关键受体结构域。最后，改变的NZW CR2等位基因导致B细胞耐受性丧失的机制将使用用于B细胞耐受性的3-83和HEL模型来表征。这些研究将阐明CR2的特定功能，在NZM 2410小鼠模型中受损，可能影响自身免疫性疾病的发展，因此是治疗干预的重要靶点。