Development of a conditional T1MP-1 knockout mouse

描述（由申请人提供）：组织金属蛋白酶抑制剂-1 （TIMP-1）是一种多营养细胞外蛋白，在炎症或损伤后在大脑中显著上调。TIMP-1作为基质金属蛋白酶（MMPs）蛋白水解活性的内源性调节剂具有良好的功能，基质金属蛋白酶（MMPs）是细胞外酶家族，在细胞稳态、适应和组织重塑中起关键作用。TIMP-1还具有与mmp无关的功能，包括抗凋亡活性和营养作用。TIMP-1的后一种功能与突触可塑性、神经保护、肿瘤发生和少突胶质细胞分化有关。TIMP-1可以在中枢神经系统的多种细胞类型中表达：星形胶质细胞在中枢神经系统炎症脱髓鞘或细菌感染时强烈表达TIMP-1，神经元在兴奋性毒性损伤后表达TIMP-1。在中枢神经系统损伤和炎症过程中，还需要指出的是，TIMP-1也通过免疫细胞表达，包括T细胞、巨噬细胞和小胶质细胞。因此，TIMP-1可以在多种细胞类型中快速表达，这为TIMP-1在中枢神经系统损伤或疾病反应中提供了无数的潜在作用。目前，只有全球的TIMP-1KO小鼠可用于研究，这意味着TIMP-1的细胞来源仍然是我们理解TIMP-1在大脑中的具体机制作用的一个混杂变量。测试特定细胞类型产生的TIMP-1是否有差异影响

DESCRIPTION (provided by applicant): Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a pleiotrophic extracellular protein that is dramatically upregulated in the brain following inflammation or injury. TIMP-1 has a well described function as an endogenous regulator of the proteolytic activities of the matrix metalloproteinases (MMPs) a family of extracellular enzymes that play critical roles in cellular homeostasis, adaptation and tissue remodeling. TIMP-1 also has noted MMP-independent functions including antiapoptotic activity and trophic actions. These latter functions of TIMP-1 have been implicated in synaptic plasticity, neuroprotection, oncogenesis and oligodendrocyte differentiation. TIMP-1 can be expressed by a variety of cell types in the CNS: astrocytes robustly express TIMP-1 in response to inflammatory demyelination or bacterial infection in the CNS, and neurons have been reported to express TIMP-1 following excitotoxic injury. In the course of CNS injury and inflammation, it is also important to point out that TIMP-1 is also expressed by immune cells, including T cells, macrophages and microglia. Thus, TIMP-1 can be rapidly expressed by a variety of cell types offering a myriad of potential roles for TIMP-1 in response to CNS injury or disease. Currently, only global TIMP-1KO mice are available for study meaning that the cellular source of TIMP-1 remains a confounding variable to our understanding on the specific mechanistic roles of TIMP-1 in the brain. To test whether production of TIMP-1 from specific cell types differentially impact neuropathology, we will develop an essential new reagent: a conditional TIMP-1 knockout mouse (TIMP-1cKO) line. This mouse line will significantly advance our understanding of TIMP-1 and its functions in the CNS by enabling us to directly test whether cell specific-TIMP-1 expression impacts the innate potential for brain recovery following injury. The first aim of this proposal will be to develop the new TIMP-1cKO mouse, which will then be crossed with the GFAP-Cre transgenic mouse to specifically knockout TIMP-1 expression from astrocytes throughout the CNS. Astrocyte-specific TIMP-1cKO mice will then be tested and compared with global. Together this work will, (a) provide a valuable new reagent for advanced study on TIMP-1 in a wide variety of disease models, including neurological diseases, and, (b) experimental results from this work will validate the TIMP-1cKO mouse as a viable new mouse line for study of cell-specific deletion of TIMP-1. PUBLIC HEALTH RELEVANCE: Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a protein that can protect the brain from injury and disease in a variety of ways. The purpose of this research project is to develop a new mouse strain where this protein can be eliminated from specific cells, and in so doing allow us to better understand how TIMP-1 can influence the behaviour of different types of cells during disease.