Czepielewski Rafael S, Gallerand Alexandre, Gilleron Jérôme, Khedher Narges, Randolph Gwendalyn J, Ivanov Stoyan
Department of Pathology and Immunology, Washington University School of Medicine.
Université Côte d'Azur; Mediterranean Center of Molecular Medicine C3M, Team 13, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1065.
J Vis Exp. 2020 Nov 19(165). doi: 10.3791/61814.
Lymphatic collecting vessels and lymph nodes are inevitably embedded in adipose tissue. The physiological significance of this observation remains still not elucidated. However, obesity is characterized by impaired lymphatic function and increased vessel permeability. Inversely, lymphatic dysfunction induces obesity in mice, suggesting a significant interplay between lymphatic vessels and the adipose tissue. Therefore, understanding factors leading to lymphatic dysfunction might open new therapeutic windows to prevent obesity and associated comorbidities. The first step in this process requires a precise and detailed visualization of the lymphatic network in healthy and inflamed adipose tissue. Here, we describe a rapid, inexpensive, and efficient method that allows to label and analyze lymphatic and blood vessels. This approach takes advantage of the skin-draining brachial lymph node localization within the subcutaneous adipose tissue. The lymphatic arborization of this tissue can be revealed by injecting fluorochrome-conjugated lectins subcutaneously. Moreover, the in vivo labeling approach provides a way to evaluate lymphatic vessel density and functions. Coupled to blood vessel, adipocyte and immune cell staining, the protocol allows for high-resolution mapping of the subcutaneous adipose tissue by 3D imaging.
淋巴管和淋巴结不可避免地嵌入脂肪组织中。这一观察结果的生理意义仍未阐明。然而，肥胖的特征是淋巴功能受损和血管通透性增加。相反，淋巴功能障碍会在小鼠中诱发肥胖，这表明淋巴管与脂肪组织之间存在重要的相互作用。因此，了解导致淋巴功能障碍的因素可能会为预防肥胖及相关合并症打开新的治疗窗口。这一过程的第一步需要精确详细地可视化健康和发炎脂肪组织中的淋巴网络。在此，我们描述了一种快速、廉价且高效的方法，可用于标记和分析淋巴管和血管。该方法利用了皮下脂肪组织中引流皮肤的臂淋巴结定位。通过皮下注射荧光染料偶联凝集素，可以揭示该组织的淋巴分支。此外，体内标记方法提供了一种评估淋巴管密度和功能的途径。结合血管、脂肪细胞和免疫细胞染色，该方案允许通过三维成像对皮下脂肪组织进行高分辨率映射。
