小鼠单疱病毒角膜炎行羊膜移植MMPs及TIMPs表达的变化

Expression of Matrix Metalloproteinase and Tissue Inhibitor of Metalloproteinase in HSV-1-infected Mice with Amniotic Membrane Transplantation

目的:探讨羊膜移植对BalB/c小鼠感染单纯疱疹病毒-1(HSV-1)后基质金属蛋白酶-2,-8,-9及组织金属蛋白酶抑制剂TIMP-1,TIMP-2表达变化及其在单疱病毒角膜炎(HSK)病程中所起的作用。方法:将40只小鼠随机分为实验组和对照组,将5μl(105PFU)HSV-1感染小鼠单侧右眼角膜,建立单疱病毒角膜炎的动物模型。对实验组小鼠右眼角膜行羊膜移植术。分别在HSV-1感染后的第2,7,14 d处死小鼠,用免疫组化方法对小鼠感染HSV-1后MMP-2、MMP-9、MMP-8、TIMP-1、TIMP-2的表达变化进行研究,探讨它们在单疱病毒性角膜炎发展过程中所起的作用。结果:在对照组,角膜中MMP-2、MMP-8、MMP-9及TIMP-1、TIMP-2在第2天出现表达且表达主要位于浅表基质层及上皮下的炎性细胞中。感染后第14天可见坏死性角膜炎及角膜溃疡形成,同时角膜基质和浸润的炎性细胞中尤其溃疡处,可见MMP-2、MMP-9及TIMP-1、TIMP-2表达显著增加。溃疡区域有大量MMP-8阳性染色的中性粒细胞。实验组各时间点MMP-2,-9,-8活性均低于对照组,TIMPS表达高于对照组。结论:行羊膜移植可抑制角膜细胞和浸润的炎性细胞分泌产生MMPs,促进TIMPS表达,可能对上皮性角膜炎与溃疡形成过程起重要的抑制作用。

Objective： To study the expression and role of matrix metalloproteinase-2, -8 and -9 （MMP- 2, MMP-8 and MMP-9）and tissue inhibitor of metalloproteinase-1 and -2 （TIMP-1 and TIMP-2） in HSV-1-infected mice with amniotic membrane transplantation. Methods： Forty BalB/c mice were divided into two groups： the experimental group and control group. Their right corneas were infected with 5 μl（105 PFU）HSV-1, then amniotic membrane transplantation （AMT） was performed in the experimental group. At different time points （2, 7 and 14 days） after infection, all the mice were sacrificed, and the expression of MMP-2, -8,and -9 and TIMP-1 and -2 in cornea were detected by immunohistochemistry. Results. In the control group, at the second day after infection, the expressions of MMP-2, -8 and -9 and TIMPs were increased in the epithelium, and were detected in the superficial stroma and in inflammatory cells beneath the epithelium. Nerotizing keratitis with corneal ulceration was detected at the 14th day post-infection, which correlated with the increased expression of MMP-2, -8, -9 and TIMPs within the stroma and in infiltrating inflammatory cells. MMP-2,-9 and TIMPs staining were particularly intense in the proximity of the ulcers. The neutrophils, which were abundant at the site of ulceration, were stained positive with MMP-8 expression. At the same time, the expression levels of MMP-2, -8 and -9 in the experimental group were lower than those in the control group, while the expressions of TIMPs were higher. Conclusion： Immediate intervention with amniotic membrane transplantation for HSV keratitis promotes the healing of corneas and prevents cornea from melting by inhibiting the production of matrix metalloproteinases in epithelium and inflammatory cells.