Gastrointestinal Research Group, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
Am J Physiol Gastrointest Liver Physiol. 2010 Jul;299(1):G43-53. doi: 10.1152/ajpgi.00228.2009. Epub 2010 Mar 18.
Intestinal mucosal integrity is dependent on epithelial function and a regulated immune response to injury. Fucosyltransferase VII (Fuc-TVII) is an essential enzyme required for the expression of the functional ligand for E- and P-selectin. Trefoil factor 3 (TFF3) is involved in both protecting the intestinal epithelium against injury as well as aiding in wound repair following injury. The aim of the present study was to assess the interplay between barrier function and leukocyte recruitment in intestinal inflammation. More specifically, we aimed to examine how targeted disruption of Fuc-TVII either in wild-type or TFF3(-/-) mice would alter their susceptibility to colonic injury. TFF3 and Fuc-TVII double-knockout mice (TFF3/Fuc-TVII(-/-) mice) were generated by mating TFF3(-/-) and Fuc-TVII(-/-) mice. Colitis was induced by administration of dextran sodium sulfate (DSS) (2.5% wt/vol) in the drinking water. Changes in baseline body weight, diarrhea, and fecal blood were assessed daily. Upon euthanasia, extents of colonic inflammation were assessed macroscopically, microscopically, and through quantification of myeloperoxidase (MPO) activity. Colonic lymphocyte subpopulations were assessed at 6 days after administration of DSS by flow cytometry and immunohistochemistry. No baseline intestinal inflammation was found in TFF3/Fuc-TVII(-/-), TFF3(-/-), Fuc-TVII(-/-), or wild-type mice. Loss of Fuc-TVII resulted in a reduction in disease severity whereas TFF3(-/-) mice were markedly more susceptible to DSS-induced colitis. Remarkably, the loss of Fuc-TVII in TFF3(-/-) mice markedly decreased the severity of DSS-induced colitis as evidenced by reduced weight loss, diarrhea, decreased colonic MPO levels and improved survival. Furthermore, the loss of TFF3 resulted in increased severity of spontaneous colitis in IL-2/beta-microglobulin-deficient mice. These studies highlight the importance of the interplay between factors involved in the innate immune response, mucosal barrier function, and genes involved in regulating leukocyte recruitment and other aspects of the immune response.
肠黏膜完整性依赖于上皮功能和对损伤的调节免疫反应。岩藻糖基转移酶 VII（Fuc-TVII）是表达 E-和 P-选择素功能配体所必需的酶。三叶因子 3（TFF3）参与保护肠上皮免受损伤以及损伤后促进伤口修复。本研究旨在评估肠内炎症中屏障功能和白细胞募集之间的相互作用。更具体地说，我们旨在研究靶向敲除 Fuc-TVII 对野生型或 TFF3（-/-）小鼠易感性的影响。TFF3 和 Fuc-TVII 双敲除小鼠（TFF3/Fuc-TVII（-/-）小鼠）通过交配 TFF3（-/-）和 Fuc-TVII（-/-）小鼠产生。通过在饮用水中给予葡聚糖硫酸钠（DSS）（2.5%wt/vol）诱导结肠炎。每天评估基线体重、腹泻和粪便血的变化。安乐死后，通过宏观、微观和髓过氧化物酶（MPO）活性定量评估结肠炎症程度。在给予 DSS 后 6 天，通过流式细胞术和免疫组织化学评估结肠淋巴细胞亚群。TFF3/Fuc-TVII（-/-）、TFF3（-/-）、Fuc-TVII（-/-）或野生型小鼠无基线肠道炎症。Fuc-TVII 的缺失导致疾病严重程度降低，而 TFF3（-/-）小鼠对 DSS 诱导的结肠炎明显更敏感。值得注意的是，Fuc-TVII 的缺失在 TFF3（-/-）小鼠中显著降低了 DSS 诱导的结肠炎的严重程度，表现为体重减轻减少、腹泻减少、结肠 MPO 水平降低和存活率提高。此外，TFF3 的缺失导致 IL-2/beta-微球蛋白缺陷小鼠自发性结肠炎的严重程度增加。这些研究强调了参与固有免疫反应、黏膜屏障功能以及调节白细胞募集和免疫反应其他方面的基因之间相互作用的重要性。
