Real Time Visualization of Obesity-Induced Inflammation in Adipose Tissue

描述(申请人提供)：肥胖引起的炎症在肥胖与心血管疾病和2型糖尿病等疾病之间的联系中发挥着重要作用。这背后的机制与在脂肪组织中发现的广泛的白细胞有关，这些白细胞分泌许多炎症介质。自从最初在脂肪中发现巨噬细胞以来，脂肪中存在的白细胞类型已经大大增加，现在包括了大多数白细胞类型。不幸的是，对这些细胞如何相互作用以及如何与脂肪细胞相互作用缺乏完整的理解，限制了该领域的进展。我们认为，我们认识上的这种差距在很大程度上是由于可用于检测脂肪中炎性细胞的有限技术。此外，我们认为有许多动态细胞事件发生在脂肪中，但没有被捕捉到。因此，本研究的目标是设计和实施一种新的方法，用于在肥胖小鼠模型中对脂肪组织进行活体显微镜检查。能够观察脂肪中白细胞的相互作用可以揭示肥胖症炎症的启动和维持机制。这一进展将是重大的，因为它有可能解开肥胖是如何产生炎症的谜团。我们将通过完成两个目标来实现我们的目标。(1)建立脂肪组织中白细胞活体显像的方法学。这将使用双光子共聚焦显微镜在活体动物身上生成脂肪的4D图像。(2)探讨肥胖对脂肪相关淋巴团(FALCs)T细胞迁移的影响。我们将使用活体显微镜来测试肥胖诱导的T细胞流出FALCs并进入脂肪以产生炎症的模型。在项目结束时，我们希望为肥胖研究人员提供一个新的标准化工具，可以生成新的模型，并为了解脂肪组织基质细胞的动态特性提供一个窗口。 公共卫生相关性：对于肥胖，脂肪组织功能障碍会导致糖尿病和代谢综合征等疾病的发展。这与炎症细胞向脂肪募集和激活密切相关。这方面的研究目前有限，因为研究人员和临床医生研究脂肪中的炎性细胞的方法很少。为了解决这个问题，我们将为肥胖研究人员开发一种新的资源，使活体脂肪组织中的炎性细胞能够可视化。

DESCRIPTION (provided by applicant): Obesity-induced inflammation plays an important role in the link between obesity and diseases such as cardiovascular disease and type 2 diabetes. The mechanism behind this relates to the wide range leukocytes found in adipose tissue that secrete numerous inflammatory mediators. Since the initial identification of macrophages in fat, the number of leukocyte types present in fat have greatly increased and now include most leukocyte types. Unfortunately, an integrated understanding of how these cells interact with each other and with adipocytes is lacking and limits progress in the field. We feel that this gap in our understanding is due in large part to the limited techniques available to assay inflammatory cells in fat. Furthermore, we feel that there are many dynamic cellular events that are occurring in fat but are not being captured. Therefore, the goal of this study is to design and implement a novel methodology for intravital microscopy on adipose tissue in mouse models of obesity. Being able to observe leukocyte interactions in fat can reveal the mechanisms involved in the initiation and maintenance of inflammation in obesity. This advance will be significant as it has the potential to unlock the mystery of how inflammation is generated in obesity. We will accomplish our goal by completing two aims. (1) To establish the methodology for intravital imaging of leukocytes in adipose tissue. This will employ two-photon confocal microscopy to generate 4D views of fat in live animals. (2) To evaluate the effects of obesity on T cell migration in relation to fat associated lymphoid clusters (FALCs). We will use intravital microscopy to test a model of obesity-induced induction of T cell flux out of FALCs and into fat to generate inflammation. At the end of the project, we hope to generate a new standardized tool for obesity researchers that can generate new models and provide a window into the dynamic properties of adipose tissue stromal cells. PUBLIC HEALTH RELEVANCE: With obesity, adipose tissue dysfunction contributes the development of diseases such as diabetes and metabolic syndrome. This is closely linked to the recruitment and activation of inflammatory cells to fat. Research in this area is currently limited due to few methods that are available to researchers and clinicians to study inflammatory cells in fat. To address this, we will develop a novel resource for obesity researchers to enable visualization of inflammatory cells in live adipose tissue.