Objective: To explore the association of the Notch1/Jagged1 pathway with the homing of mesenchymal stem cells (BMSCs) to regulate Th1/Th2 drift in asthma.
Methods: Twenty SD rats were randomly divided into normal control group, model group, BMSC transplantation group, and BMSC+Notch inhibitor group. Ovalbumin sensitization was used to establish rat models of asthma, and BMSCs were transplanted via the tail vein. The pathology of the lung tissue was examined with HE staining, and the contents of interleukin (IL)-5, IL-13, and interferon-γ (IFN-γ) in lung tissue homogenate were determined with enzyme-linked immunosorbent assay. The expressions of Notch1 and Jagged1 mRNA were detected with RT-PCR, and CXCR4 expression in the bronchial epithelial cells was examined using immunofluorescence staining; Western blotting was used to detect the protein expressions of T-bet, GATA-3, Notch1, and Jagged1 in the lung tissue.
Results: Compared with those in the control group, the expressions of IFN-γ and T-bet proteins decreased significantly and the pulmonary expressions of IL-5, IL-13, and GATA-3 proteins as well as Notch1 and Jagged1 mRNA and protein expressions all increased significantly in the model group (P < 0.05 or 0.01). Compared with those in the model group, CXCR4, IFN-γ, and T-bet protein expressions in BMSC group and BMSCs+Notch inhibitor group all increased significantly, and Notch1 and Jagged1 protein expressions in BMSCs group and IL-5, IL-13, Notch1, and Jagged1 mRNA and protein expressions in BMSCs + Notch inhibitor group all decreased significantly (P < 0.05 or 0.01). The expressions of CXCR4 and IFN-γ were significantly higher and the expressions of IL-13 and Notch1 mRNA were significantly lower in BMSCs+Notch inhibitor group than in BMSC group (P < 0.05).
Conclusion: In asthmatic rats, the homing of the BMSCs to the lung tissue has a regulatory effect on Th1/Th2 drift, and the Notch1/Jagged1 pathway may participate in the homing of the BMSCs.
目的: 观察间充质干细胞（BMSCs）归巢调节哮喘Th1/Th“ 2漂移”与Notch1/Jagged1通路的关系。
方法: 20只SD大鼠用随机数字表法均分为4组：正常对照组（NC）、模型对照组（MC）、BMSCs移植组（BMSCs）、BMSC+Notch抑制剂组。采用卵清蛋白致敏和激发建立哮喘模型，尾静脉注射BMSCs。HE染色观察肺组织病理形态学，酶联免疫吸附法检测肺组织白介素（IL）-5、IL-13、IFN-γ，RT-PCR法检测肺组织Notch1、Jagged1基因表达，免疫荧光染色检测支气管上皮细胞中CXCR4蛋白表达，免疫印迹法检测肺组织T-bet、GATA-3、Notch1、Jagged1蛋白表达。
结果: 与NC组比较，MC组IFN-γ、T-bet蛋白表达降低，IL-5、IL-13、GATA-3蛋白表达升高，Notch1、Jagged1mRNA和蛋白表达升高（P＜0.05或P＜0.01）。与MC组比较，BMSCs组、BMSCs+Notch抑制剂组CXCR4、IFN-γ、T-bet蛋白表达量显著升高，BMSCs组Notch1、Jagged1蛋白表达降低，BMSCs+Notch抑制剂组IL-5、IL-13、Notch1、Jagged1mRNA和蛋白降低（P＜0.05或P＜0.01）。与BMSCs组比较，BMSCs+Notch抑制剂组CXCR4、IFN-γ表达升高，IL-13、Notch1mRNA表达降低（P＜0.05）。
结论: BMSCs向哮喘肺组织归巢对Th1/Th2 “漂移”产生调节作用，Notch1/ Jagged1通路可能参与其过程。
Keywords: Notch1/Jagged1 signaling pathway; Th1/Th2 drift; asthma; bone mesenchymal stem cells; homing.