Genetics of Cartilage Regeneration and Osteoarthritis

描述（由申请人提供）：本提案来自矫形外科和细胞生物学系的软骨生物学家琳达·桑德尔博士和解剖学和神经生物学系的群体遗传学家和形态学家詹姆斯·切弗鲁德博士。使用与“超级愈合”小鼠相关的品系（重组近交系和高级杂交），我们定义了关节软骨再生和耳组织再生的表型，并在这两种表型之间建立了强正相关性。此外，概念验证研究表明，愈合关节软骨的能力可能与防止创伤后骨关节炎有关。这种独特的遗传资源将用于测试耳创伤愈合，软骨再生和骨关节炎之间的关联，并系统地识别有助于软骨再生的基因，从而促进骨关节炎的发展。目前赠款建议的具体目标是：（1）在LG/J和SM/J的重组近交系中测试关节软骨再生和骨关节炎之间的相关性，映射到约10 cM。（2）确定关节软骨再生和骨关节炎在LG/J和SM/J的高级杂交中的分布，将这些区域映射到包含1-5个基因的亚cM间隔（3）确定负责代表极端愈合的菌株中的软骨和干细胞应答中的已建立菌株差异的细胞和分子机制，以及（4）使用系统教育的候选基因方法，通过我们的“借一只耳朵治疗骨关节炎”活动验证基因。用于实现这些特定目标的方法依赖于具有不同再生软骨和耳组织能力的LG/J和SM/J的重组近交和高级杂交株的可用性，结合用于关节软骨创伤和内侧半月板不稳定的小鼠手术技术（DMM骨关节炎模型），通过组织学和显微CT分析。软骨和干细胞的功能分析将在极端愈合的菌株中进行。基因参与的证据将通过在敲除小鼠中使用DMM骨关节炎模型来建立。该项目的成果将是鉴定影响小鼠骨关节炎发展和关节软骨再生的基因，为探索人类基因组提供高质量的候选基因。

DESCRIPTION (provided by applicant): This proposal is from Dr. Linda Sandell, a cartilage biologist in the Departments of Orthopaedic Surgery and Cell Biology and Dr. James Cheverud, a population geneticist and morphologist in the Department of Anatomy and Neurobiology. Using strains related to the "super healing" mouse (both recombinant inbred strains and an advanced intercross), we have defined phenotypes of articular cartilage regeneration and ear tissue regeneration and established a strong positive correlation between these two phenotypes. Furthermore, proof- of-concept studies demonstrate that the ability to heal articular cartilage may be associated with protection from post-traumatic osteoarthritis. This unique genetic resource will be used to test the association between ear wound healing, cartilage regeneration and osteoarthritis and to systematically identify genes that contribute to cartilage regeneration and thus to osteoarthritis development. The specific aims of the current grant proposal are: (1) Test the correlation between articular cartilage regeneration and osteoarthritis in recombinant inbred lines of LG/J and SM/J, mapping to approximately 10 cM (2) Determine the distribution of articular cartilage regeneration and osteoarthritis in the advanced intercross f LG/J and SM/J, mapping these regions to sub-cM intervals containing 1-5 genes (3) Determine the cell and molecular mechanisms responsible for established strain differences in cartilage and stem cell responses in the strains that represent extremes of healing, and (4) Using a systems-educated candidate gene approach, validate genes through our "Lend an Ear for Osteoarthritis" Campaign. The methods used to undertake these specific aims rely on the availability of recombinant inbred and advanced intercross strains of LG/J and SM/J with different abilities to regenerate cartilage and ear tissue combined with mouse surgical techniques for articular cartilage wounding and destabilization of the medial meniscus (DMM osteoarthritis model), analyzed by histology and micro-CT. Functional analyses of cartilage and stem cells will be performed in the strains that are extremes of healing. Proof of gene involvement will be established by using the DMM osteoarthritis model in knock-out mice. The outcome of this project will be the identification of genes affecting osteoarthritis development and articular cartilage regeneration in mice, providing high-quality candidates for probing the human genome.