Transgenic ES Cell Differentiation Systems to replace Transgenic Mouse Analysis of Tissue Specific Regulatory Elements

了解基因是如何调控的，对正常发育和癌症等疾病的进展都有重要意义。对于一个特定的细胞或组织的发展，适当的基因组必须在一个严格控制的过程中被激活。控制整体基因活化的调控元件目前使用基于细胞的测定和转基因小鼠的组合来鉴定，以评估它们在其中具有活性的细胞类型。以这种方式分析调控因素的一个主要缺点是动物福利问题，涉及小鼠所经历的程序以及所需小鼠的数量。在这里，我们建议开发的试剂和协议，将取代使用转基因小鼠在体外基于胚胎干细胞（ES）分化测定。ES细胞易于进行遗传操作，并且在适当的培养条件下具有发育成许多不同细胞类型的潜力。我们计划在ES细胞分化过程中系统地测试调控元件，并验证可以以这种方式研究的细胞类型，以证明ES细胞分化为评估基因调控功能提供了一种可行的替代方案。通过提供合适的工具和方案，我们的目标是鼓励更广泛的科学界采用基于ES细胞的系统来分析基因调控，从而大大减少用于此类研究的动物数量。此外，这项研究将有助于确定在具有潜在治疗益处的各种细胞类型中具有特异性活性的调控元件，例如免疫细胞或产生胰岛素的胰腺细胞。工程化的ES细胞携带这种细胞类型特异性调控元件将为开发生产这些细胞的新方案提供强大的工具，因此对于利用胚胎干细胞用于再生医学的前景至关重要。

Understanding how genes are regulated has important implications in both normal development and in the progression of diseases such as cancer. For a specific cell or tissue to develop, the appropriate set of genes must be activated in a tightly controlled process. Regulatory elements that control overall gene activation are currently identified using a combination of cell based assays and transgenic mice to assess the cell types in which they are active. A major drawback of analysing regulatory elements in this way are the animal welfare issues concerning both the procedures that the mice undergo as well as the numbers of mice required. Here, we are proposing to develop reagents and protocols that will replace the use of transgenic mice with in vitro based embryonic stem (ES) cell differentiation assays. ES cells readily undergo genetic manipulation and under appropriate culture conditions have the potential to develop into many different cell types. We plan to systematically test regulatory elements during ES cell differentiation and validate the cell types that can be studied in this way in order to demonstrate that ES cell differentiation provides a viable alternative for assessing gene regulatory function. By providing suitable tools and protocols we aim to encourage the wider scientific community to adopt ES cell based systems for analysing gene regulation thereby dramatically reducing the numbers of animals used in this kind of research. In addition, this study will help to identify regulatory elements that are specifically active in various cell types with potential therapeutic benefits such as immune cells or insulin producing pancreatic cells. ES cells engineered to carry such cell-type specific regulatory elements will provide powerful tools for the development of new protocols for producing these cells and will therefore be vital to harness the promise of embryonic stem cells for regenerative medicine.