The Role of Immunoglobulin CDRH3 in Autoimmune Disease

免疫球蛋白 CDRH3 在自身免疫性疾病中的作用

• 批准号: 8513453
• 负责人: Harry William Schroeder
• 金额: $ 36.63万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8513453
• 关键词: Accounting; Address; Affect; African; Aging; Alleles; American; Amino Acid Sequence; Amino Acids; Anti-DNA Antibodies; Antibodies; Antibody Formation; Antibody Repertoire; Appearance; Arginine; Autoantibodies; Autoantigens; Autoimmune Diseases; Autoimmune Process; B cell repertoire; B-Cell Development; B-Lymphocytes; Binding; Binding Sites; Breeding; C57BL/6 Mouse; Characteristics; Charge; Communities; Congenic Mice; Death Rate; Development; Disease; Ethics; Failure; Female; Foundations; Funding; Gene Targeting; Genes; Glean; Glycine; Goals; Health Expenditures; Hispanic Americans; Human; Immune system; Immunoglobulin G; Immunoglobulin Genes; Immunoglobulins; Inbred BALB C Mice; Individual; Infection; Inflammatory; Laboratories; Learning; Life Expectancy; Lupus; Lupus Nephritis; Mature B-Lymphocyte; Medical Research; Modeling; Morbidity - disease rate; Mouse Strains; Mus; Nephritis; Outcome; Pathogenesis; Plant Roots; Positioning Attribute; Predisposition; Prevention; Process; Production; Publishing; Reading Frames; Regulation; Reporting; Research; Resistance; Rest; Rheumatism; Role; SLEB1 gene; SLEB2 gene; SLEB3 gene; Structure; Susceptibility Gene; System; Systemic Lupus Erythematosus; Testing; Time; Tyrosine; Vaccines; Valine; Woman; Work; aged; anti-dsDNA antibodies; antigen binding; base; congenic; design; improved; innovation; insight; lupus like nephritis; mouse model; neoplastic; novel; overexpression; pathogen; prevent; resistant strain; response

DESCRIPTION (provided by applicant): Systemic lupus erythematosus (SLE) is a common multisystem autoimmune disease that is estimated to affect more than 500,000 Americans. Our goal is to gain a better understanding of the mechanisms that normally prevent expression of the self-reactive antibodies that cause the disease as well as to better understand where and how these mechanisms fail. Research into fundamental causes of disease in humans is often impossible due to ethical considerations. Decades of medical research attest to the usefulness of mouse models as a means to identify root causes as well as new avenues for treatment and prevention. The presence of the sle1, sle2, and/or sle3/5 NZM2410 lupus loci in C57BL/6 mice promotes development of an autoantibody driven disorder that shares many of the features of human SLE. It is our hypothesis that failure to properly regulate one specific part of the antibody, CDR-H3, in susceptible individuals facilitates production of anti-DNA antibodies and triggers disease. CDR-H3 is critical because it is created de novo by VDJ joining and it lies at the very center of the antigen binding site. In the past funding period, we finished creating a novel set of D- altered mouse strains, each of which incorporates one of three different DH alleles, each limited to a single DH gene segment. The first contains a single, normal DH as a control for the loss of the rest of the DH locus. This DH incorporates tyrosine and glycine in preferred reading frame 1 (RF1). The second forces use of inverted RF1, replacing tyrosine and glycine residues with arginine. The third forces use of RF2, replacing tyrosine and glycine residues with valine instead of arginine. We created these alleles in BALB/c, and then bred them onto C57BL/6 (N22). We showed that the sequence of the DH has a dominant effect on CDR-H3 content, B cell development and antibody production. In previously supported studies, we have documented that enrichment for arginine in the DH enhances expression of arginine in CDR-H3 and, with aging, promotes the development of IgG anti-dsDNA antibodies in BALB/c mice. We now propose to use our D-altered mice to test whether genes within the sle1, sle2, and/or sle3/5 NZM2410 lupus loci alter regulation of the amino acid content of CDR-H3 and/or the development of B cells that express charged CDR-H3 intervals. We will test whether early and enhanced expression of arginine in CDR-H3 in the presence of one or more of the sle1, sle2, and/or sle3/5 NZM2410 lupus loci in C57BL/6 mice will promote early expression of IgG anti-dsDNA antibodies and accelerate the development of autoimmune disease. We will then breed our D-altered mice onto B6 mice congenic for individual susceptibility genes or sub-intervals within the sle1, sle2, and/or sle3/5 loci in order to identify the specific genes, and by extension, the mechanisms that regulate CDR-H3 content and anti-dsDNA activity and assess their relationship to the development of nephritis. We predict that the information we glean from our studies will help us learn how to prevent lupus, as well as control humoral responses to pathogens, vaccines, and altered-self antigens.

描述（由申请人提供）：系统性红斑狼疮（SLE）是一种常见的多系统自身免疫性疾病，估计影响超过50万美国人。我们的目标是更好地了解通常阻止导致疾病的自身反应性抗体表达的机制，以及更好地了解这些机制在何处以及如何失败。由于伦理方面的考虑，对人类疾病的根本原因的研究往往是不可能的。数十年的医学研究证明了小鼠模型作为确定根本原因以及治疗和预防新途径的有效性。C57 BL/6小鼠中sle 1、sle 2和/或sle 3/5 NZM 2410狼疮基因座的存在促进了自身抗体驱动的疾病的发展，该疾病具有人类SLE的许多特征。我们的假设是，在易感个体中，未能正确调节抗体的一个特定部分CDR-H3，会促进抗DNA抗体的产生并引发疾病。CDR-H3是关键的，因为它是通过VDJ连接从头产生的，并且它位于抗原结合位点的正中心。在过去的资助期内，我们完成了一组新的D-改变小鼠品系的创建，其中每一种都包含三种不同DH等位基因中的一种，每一种都限于单个DH基因片段。第一个包含单个正常DH作为DH基因座其余部分丢失的对照。该DH在优选的阅读框1（RF 1）中掺入酪氨酸和甘氨酸。第二个强制使用反向RF 1，用精氨酸取代酪氨酸和甘氨酸残基。第三种迫使使用RF 2，用缬氨酸代替精氨酸取代酪氨酸和甘氨酸残基。我们在BALB/c中创建了这些等位基因，然后将它们繁殖到C57 BL/6（N22）上。我们发现DH的序列对CDR-H3含量、B细胞发育和抗体产生具有显性影响。在先前支持的研究中，我们已经证明DH中精氨酸的富集增强了CDR-H3中精氨酸的表达，并且随着年龄的增长，促进了BALB/c小鼠中IgG抗dsDNA抗体的产生。我们现在建议使用我们的D-改变小鼠来测试sle 1，sle 2和/或sle 3/5 NZM 2410狼疮基因座内的基因是否改变CDR-H3的氨基酸含量的调节和/或表达带电CDR-H3间隔的B细胞的发育。我们将测试在C57 BL/6小鼠中存在sle 1、sle 2和/或sle 3/5 NZM 2410狼疮基因座中的一个或多个的情况下，CDR-H3中精氨酸的早期和增强表达是否会促进IgG抗dsDNA抗体的早期表达并加速自身免疫性疾病的发展。然后，我们将我们的D-改变的小鼠与B6小鼠交配，这些小鼠与sle 1、sle 2和/或sle 3/5基因座内的单个易感基因或子区间同源，以鉴定特定基因， 延伸，调节CDR-H3含量和抗dsDNA活性的机制，并评估它们与肾炎发展的关系。我们预测，我们从研究中收集的信息将帮助我们了解如何预防狼疮，以及控制对病原体，疫苗和改变自身抗原的体液反应。