肠系膜脂肪组织肥厚及爬行脂肪变是克罗恩病（CD）所特有的组织病理学特征，肠系膜脂肪通过其表达的脂肪因子在CD的发生及发展中起到关键的作用。肠道淋巴系统功能障碍是导致CD黏膜水肿及肠道炎症的重要机制。脂肪因子Apelin具有促进淋巴管生成、维持淋巴管功能的重要作用。本课题组前期研究发现CD患者肠系膜切缘Apelin的低表达与术后复发存在显著相关性；予以Apelin能够明显减轻CD模型小鼠的肠道炎症。在前期研究基础上，本课题以CD模型小鼠及CD患者肠系膜脂肪组织为研究对象，采用体内研究与体外研究相结合，通过免疫组化、分子生物学及分子免疫学等技术，着眼于肠道炎症，基于淋巴内皮细胞，从肠系膜组织角度探讨调节Apelin对CD的作用机制，探索肠系膜脂肪因子Apelin与淋巴内皮细胞相互作用在CD肠道炎症中的作用，为阐释 CD 病理生理奠定理论基础，为CD防治提供新的靶点。

Fat wrapping or creeping fat, characterized by a hypertrophy of the mesenteric fat surrounding the inflamed intestinal segments is the unique feature of Crohn’s disease (CD). Accumulated data indicate that the mesenteric adipose tissue (MAT) plays an important role in the pathogenesis of CD through the expression of adipokines including apelin which has been demonstrated to be critical in the lymphatic development and in the stabilization of lymphatic vessels. Lymph flow is a critical determinant of antigen and dendritic cell transport while lymphatic obstruction, remodeling and impaired contraction may lead to repeated rounds of lymphangiogenesis and the subsequent intestinal inflammation in CD. We recently found that the expression of apelin in the margin of MAT was inversely associated with the postoperative recurrent CD. Furthermore, administration of apelin can effectively attenuated the intestinal inflammation in CD animal model, suggesting the important role played by apelin in CD. Based on our preliminary results, on the standing of MAT, we proposed a study performing in vivo and in vitro which will focus on the cross-talk between apelin and lymphatic endothelium in CD, and further exploring the potential mechanisms of the effects of apelin on lymphatic vessels, by molecular biology techniques. The results of our study would provide evidence to the understanding of the pathogenesis of CD, and may also shed light on the clinical management for CD.