中文摘要：

目的：本课题组前期工作已经证明阻断Notch信号对角质形成细胞的分泌功能有所影响,使其分泌的多种促纤维化因子发生改变。本实验将探讨在复合培养的条件下,通过调节角质形成细胞中的Notch信号,了解其对成纤维细胞collagen-1合成的影响。方法：运用角质形成细胞-成纤维细胞复合培养的模型,于复合培养前3天进行血清刺激或者γ-分泌酶抑制剂DAPT阻断角质形成细胞中的Notch信号,即在角质形成细胞分化前进行干预。然后提升至气液交界面使其达到复层生长和终末分化,后与成纤维细胞共培养,观察阻断Notch信号后的角质形成细胞对成纤维细胞合成collagen-1的影响。结果：在分化前,给予角质形成细胞血清刺激,在复合培养0小时,Notch-1、Jagged-1表达明显升高（P〈0.05）,在复合培养第一天,p21表达上调、p63表达下降（P〈0.05）,表明在复合培养时,角质形成细胞中的Notch信号明显活化。通过在血清刺激前给予DAPT预处理,在复合培养0小时,角质形成细胞中Notch信号下游分子p21和p63的表达恢复至无血清刺激水平（P〈0.05）,表明DAPT组确实阻断了角质形成细胞中的Notch信号。而DAPT组的成纤维细胞collagen-1的表达相对于血清刺激组明显下降,而与无血清组无明显差异,表明阻断Notch信号后的角质形成细胞在复合培养条件下,确实能够抑制成纤维细胞collagen-1的表达,使其合成collagen-1的量恢复至无血清刺激水平。结论：DAPT能够阻断Notch信号的活化,用阻断Notch信号后的角质形成细胞与成纤维细胞共培养,能够明显抑制成纤维细胞合成Ⅰ型胶原的能力,从而抑制瘢痕的增生。

英文摘要：

Objective： The previous study showed that blocking Notch signaling could suppress the promotion of fibrotic cytokines production in keratinocytes. And now, we study the impact of expression of collagen-1 in fibroblasts which are co-culturing with Notch signaling occurred keratinocytes. Methods： To use keratinocytes which were stimulated by serum or pretreated by DAPT （inhibitor of 3,-secretase） to block Notch signaling （before the terminal differentiation in keratinocytes） co-cultured with fibroblasts, and detect the impact of expression of collagen-1 in fibroblasts. Results： To stimulate the keratinocytes with 10 %, FCS before the terminal differentiation, the expression of Notch-1 and Jagged-1 up-regnlated at 0 hour of co-culture （P〈0.05）. And the expression of downstream gene p21 increased, but p63 decreased on the first day of co-culture （P〈0.05）, which meant the Notch signaling were activated in keratinocytes with serum-stimulation. However, the DAPT group which pretreated by DAPT, the expression of p21 and p63 had no significant difference compared to serum-flee group, suggesting DAPT exactly blocked the Notch signaling in keratinocytes. And the expression of collagen-1 in fibroblasts of DAPT group had significant decreased compared to serum-stimulated group, but almost had no differences with serum-flee group, indicating the expression of collagen-1 was inhibited in fibroblasts of DAPT group, and the level of collagen-1 had no significant difference with serum-free group. Conclusions： DAPT can block the activity of Notch signaling in keratinocytes, and when keratinocytes co-culturing with fibroblasts, blocking Notch signaling pathway in keratinocyte could suppress the expression of collagen-1 in fibroblasts.