Establishing a new genetic mouse model of osteoarthritis

建立新型骨关节炎基因小鼠模型

基本信息

批准号：
9979381
负责人：
DAVID J. GRUNWALD
金额：
$ 22.88万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-11 至 2022-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9979381
关键词：
Address Adult Affect Aging Alleles Amino Acid Substitution Animal Model Animals Arthritis Biological Biological Assay Biological Process Bone Spur C57BL/6 Mouse Candidate Disease Gene Cartilage Cells Code Degenerative polyarthritis Development Disease Disease Progression Drug Screening Etiology Event Family Functional disorder Future Gene-Modified General Population Genes Genetic Goals Homeostasis Human Hyperactive behavior Immune response Inbred Strains Mice Individual Inflammation Inflammatory Inflammatory Response Injury Intervention Invaded Joints Knee joint Link Maintenance Measurable Mechanics Modeling Molecular Mus Operative Surgical Procedures Organ Pain Pathway interactions Pattern Recognition Pattern recognition receptor Pharmaceutical Preparations Phosphotransferases Physiological Physiology Predisposition Process Production Proteins RIPK2 gene Replacement Arthroplasty Replacement Therapy Research Risk Role Sclerosis Severities Signal Pathway Signal Transduction Study models Surface Susceptibility Gene Testing Therapeutic Intervention Tissues United States Variant aged aging population base bone cartilage degradation cell type disability effective therapy experience gain of function genetic variant high reward immunoregulation joint injury mouse model palliative pre-clinical precise genome editing prevent programs protein function receptor subchondral bone

项目摘要

Osteoarthritis (OA) is the major cause of disability among the aging, affecting more than 30 million adults in the US. It is a painful and debilitating disease involving abnormal remodeling of joint tissues. No cure for OA exists and surgical intervention is the only effective therapy. No known treatment prevents initiation or progression of the disease. Lack of understanding of the genes, molecular pathways, and biological processes underlying susceptibility to OA is the key limitation to the development of effective therapies. As noted in the FOA (16- 240) to which this proposal responds: “little is understood about the initial changes triggering disease etiology and early progression.” Our goal is to identify molecular pathways that are vulnerability points for the development of OA: We first discover human gene variants associated with susceptibility to OA and then determine whether and how these gene variants confer susceptibility to OA in genetically modified mouse models. We predict the pathways perturbed by these alleles are pathways whose normal functions guard against OA. We hypothesize these are the pathways that are eroded or compromised during aging. We have identified four families that harbor strongly supported OA-susceptibility variants in genes encoding components of the NOD-RIPK2 signaling pathway. This pathway uses NOD pattern recognition receptors to sense breakdown products and promote inflammatory signaling that directs tissue homeostasis. We propose modulation of NOD-RIPK2 signaling can contribute to OA susceptibility. In this proposal we test whether a rare RIPK2 variant, which segregates with OA and is hyperactive in signaling, affects normal physiology and/or joint maintenance in mice and is sufficient to confer susceptibility to OA in mice. We generated a precisely modified C57Bl/6 mouse that carries the variant protein-coding allele. In two aims we will test if the variant RIPK2104Asp allele: 1) causes an aberrantly prolonged or sustained inflammatory response; 2) alters maintenance of the joint in naturally aging mice; and 3) enhances the onset and/or severity of OA initiated by mechanical injury to the knee joint. The scientific premise for study of the mouse model is strong. The RIPK2 allele segregates as a highly penetrant dominant factor linked to OA and the OA-associated RIPK2 product has increased signaling activity relative to the wildtype protein. Recently we demonstrated the single amino acid substitution has a measurable effect on the immune response of B6 mice. We hypothesize the RIPK2 variant acts as a gain- of-function allele to over-stimulate the inflammatory response to naturally occurring or induced joint damage. Our studies will determine if the RIPK2 allele is sufficient to increase susceptibility to OA in mice, begin to test the link between the NOD-RIPK2 inflammation pathway and OA, and determine types of initiating events that trigger this pathway. Having a mouse model of an allele linked to a common, idiopathic form of OA will allow us in the future to identify i) specific cell types and biological pathways that are key to vulnerability to OA and ii) additional factors that interact with and exacerbate the effect of RIPK2 signaling on OA.

骨关节炎（OA）是衰老中残疾的主要原因，影响了超过3000万成年人我们。这是一种痛苦而令人衰弱的疾病，涉及关节组织的异常重塑。无法治愈OA 手术干预是唯一有效的疗法。没有已知的治疗可以阻止主动或进展疾病。缺乏对基因，分子途径和生物学过程的理解 OA的敏感性是开发有效疗法的关键限制。如FOA中所述（16- 240）此提案回应：“关于触发病因的最初变化几乎没有理解我们的目标是确定是脆弱点的分子途径 OA的发展：我们首先发现与OA易感性相关的人类基因变异确定这些基因变体是否以及如何在一般修饰的鼠标中会易于OA的敏感性型号。我们预测这些等位基因扰动的途径是正常功能守护的途径反对OA。我们假设这些是在衰老过程中侵蚀或损害的途径。我们已经确定了四个家庭，这些家庭在编码的基因中强烈支持OA支持性变体 NOD-RIPK2信号通路的组件。该途径使用点头模式识别受体感官分解产物并促进指导组织稳态的炎症信号传导。我们建议 NOD-RIPK2信号传导的调节可能有助于OA敏感性。在此提案中，我们测试是否罕见 RIPK2变体与OA分离并在信号传导方面具有多动，会影响正常生理和/或关节小鼠的维护足以使小鼠对OA的敏感性。我们生成了一个经过精确修改的携带变体蛋白质编码等位基因的C57BL/6小鼠。在两个目标中，我们将测试变体RIPK2104ASP是否等位基因：1）引起异常延长或持续的炎症反应； 2）改变维护的自然老化小鼠的关节； 3）增强了通过机械损伤引发的OA的发作和/或膝关节。研究小鼠模型的科学前提很强。 RIPK2等位基因将与OA相关的高渗透率主要因素和与OA相关的RIPK2产品具有增加的信号传导相对于野生型蛋白的活性。最近我们证明了单个氨基酸取代对B6小鼠的免疫响应的可测量作用。我们假设RIPK2变体是增益 - 功能性等位基因过度刺激对天然或诱发关节的炎症反应损害。我们的研究将确定RIPK2等位基因是否足以增加小鼠OA的敏感性，开始测试NOD-RIPK2注入途径和OA之间的链接，并确定启动的类型触发这一路径的事件。具有与OA的常见特发性形式相关的等位基因的鼠标模型将来将允许我们识别i）特定的细胞类型和生物学途径，这是脆弱性的关键 OA和II）与RIPK2信号对OA相互作用并加剧的其他因素。