Establishing a new genetic mouse model of osteoarthritis

建立新型骨关节炎基因小鼠模型

• 批准号: 10260515
• 负责人: DAVID J. GRUNWALD
• 金额: $ 19.06万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-11 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10260515
• 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; Hyperactivity; 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

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.

骨性关节炎(OA)是导致老年人残疾的主要原因，影响着3000多万成年人 我们。这是一种疼痛和虚弱的疾病，涉及关节组织的异常重塑。目前尚无治疗骨性关节炎的良方 手术治疗是唯一有效的治疗方法。目前尚无已知的治疗方法可预防该病的发生或进展 这种疾病。缺乏对潜在的基因、分子途径和生物过程的了解 对骨性关节炎的易感性是开发有效治疗方法的关键限制。正如FOA所指出的(16- 对于这一点，这一提议回应道：“人们对引发疾病病因学的最初变化知之甚少 和早期进展。我们的目标是找出易受感染的分子途径。 骨性关节炎的发展：我们首先发现了与骨性关节炎易感性相关的人类基因变异，然后 确定这些基因变异是否以及如何增加转基因小鼠对骨性关节炎的易感性 模特们。我们预测，被这些等位基因干扰的通路是其正常功能保护的通路 反对美国国税局。我们假设这些是在衰老过程中被侵蚀或破坏的通路。 我们已经确定了四个家族，它们在编码的基因中存在强烈支持的OA易感变异 NOD-RIPK2信号通路的组成部分。这一途径使用结节模式识别受体来 感知分解产物，促进炎症信号，引导组织动态平衡。我们建议 NOD-RIPK2信号的调节可能与骨关节炎的易感性有关。在这项提案中，我们测试了一种罕见的 RIPK2变异体与骨性关节炎分离，并在信号转导中高度活跃，影响正常生理和/或关节 在小鼠中维持，并足以使小鼠对骨性关节炎易感。我们生成了一个经过精确修改的 携带变异蛋白编码等位基因的C57BL/6小鼠。我们将在两个目标中测试RIPK2104Asp变体 等位基因：1)引起异常延长或持续的炎症反应；2)改变 3)增强由机械损伤引发的骨性关节炎的发病和/或严重程度。 膝关节。研究小鼠模型的科学前提是强有力的。RIPK2等位基因分离为 与骨质疏松症和骨质疏松症相关的RIPK2产物相关的高渗透性主导因子增加了信号转导 相对于野生型蛋白的活性。最近，我们证明了单一氨基酸的替代具有 对B6小鼠免疫反应有明显影响。我们假设RIPK2变体作为一种增益- 对自然发生或诱导的关节过度刺激炎症反应的功能缺失等位基因 损坏。我们的研究将确定RIPK2等位基因是否足以增加小鼠对OA的易感性， 开始检测NOD-RIPK2炎症通路与骨性关节炎之间的联系，并确定启动类型 触发这一途径的事件。具有与一种常见的特发性骨性关节炎相关联的等位基因的小鼠模型 将使我们在未来能够识别i)特定的细胞类型和生物途径，这些细胞类型和生物途径是导致 和ii)与RIPK2信号相互作用并加剧对OA影响的其他因素。