IMAGE-GUIDED INJECTION WITH A HIGH-RESOLUTION ULTRASOUND SYSTEM ADAPTED FOR RODENT USE

生物是由细胞组成的，这些细胞聚集在一起形成器官，这些器官进一步组织成功能系统，如呼吸系统，骨骼系统，消化系统，神经系统和免疫系统。申请资助的目的是获得免疫系统的知识;特别是，我们专注于称为T细胞的白色血细胞的子集。T细胞在一个叫做胸腺的器官中通过一系列明确的细胞阶段发育。这些不同的细胞阶段依赖于高度保守的分子过程。因此，T细胞是研究细胞和分子生物学的一个很好的模型，因为这些不同的细胞阶段可以很容易地被识别，分离和修饰。 我们是一个由五位科学家组成的小组，共同研究驱动T细胞发育和功能的细胞和分子相互作用的不同方面。具体来说，我们的团队包括一名免疫遗传学家、一名分子免疫学家、一名细胞免疫学家、一名血管生物学家和一名生物药理学家。我们方法的多样性带来了原创性和创造性的项目以及新工具和技术的开发。我们研究的性质要求我们研究生理系统中复杂的细胞相互作用。因此，小鼠代表了我们研究的首选模型。描述特定基因、蛋白质或细胞在T细胞发育中的功能的最有效方法之一是从一只小鼠的胸腺中分离T细胞，并将其转移到另一种小鼠品系的胸腺中。然后，我们研究了受体小鼠中的T细胞，例如缺乏特定基因，以确定该基因对T细胞发育和功能的影响。 为了将这些细胞转移到活小鼠的胸腺中，我们以前采用了不可靠的方法，这是发现和科学进步的障碍;此外，由于成功率低，以前的方法现在被我们的伦理委员会拒绝。我们请求购买一种图像引导注射系统，该系统使用适用于小鼠的高分辨率超声。该设备操作方便，因此我们所有的人员都可以迅速接受培训，独立进行细胞转移。对于所有经过培训的用户来说，使用该系统进行细胞转移的成功率超过95%。除了显著增加研究产出外，根据加拿大动物护理理事会现行的道德准则，需要使用的动物将减少。因此，我们有科学和道德义务改变我们的做法，并开始常规使用高分辨率超声系统在小鼠体内研究。

Living beings are composed of cells which are grouped together to form organs that are further organized into functional systems such as the respiratory, skeletal, digestive, nervous, and immune systems. The objective of the grant application is to gain knowledge on the immune system; in particular, we focus on a subset of white blood cells called T cells. T cells develop through a series of well-defined cellular stages in an organ called the thymus. These different cell stages rely on highly conserved molecular processes. As such, T cells are a great model to study cellular and molecular biology due to the ease with which these different cell stages can be identified, isolated, and modified. We are a group of five scientists working together to understand different aspects of the cellular and molecular interactions driving T cell development and function. Specifically, our group includes an immunogeneticist, a molecular immunologist, a cellular immunologist, a vascular biologist and a biophysicist. The diversity in our approaches has given rise to original and creative projects as well as to the development of new tools and techniques. The nature of our research requires that we study complex cell interactions in a physiological system. As such, the mouse represents the model of choice for our studies. One of the most effective means to delineate the function of specific genes, proteins, or cells in T cell development is to isolate T cells from the thymus of one mouse and transfer them into the thymus of another mouse strain. We then study T cells in the recipient mouse, lacking a specific gene for instance, to define the impact of that gene on T cell development and function. To perform these cell transfers into the thymus of live mice, we previously resorted to unreliable methods that are a barrier to discovery and the advancement of science; in addition, previous approaches are now rejected by our ethics board due to low success rates. We request the purchase of an image-guided injection system using high-resolution ultrasound adapted for use in mice. This device is user-friendly, such that all our personnel can rapidly be trained to independently carry out the cell transfers. The success rate of cell transfers with this system exceeds 95% for all trained users. In addition to significantly increasing research output, fewer animals will need to be used, in compliance with current ethical guidelines from the Canadian Council on Animal Care. We thus have a scientific and moral obligation to change our practices and begin routinely using high-resolution ultrasound system for in vivo studies in mice.