小鼠单纯疱疹病毒性角膜炎中基质金属蛋白酶-2、8、9阳性细胞计数及意义

目的探讨单纯疱疹病毒性角膜炎小鼠角膜中基质金属蛋白酶(MMP)-2、8、9阳性细胞计数、细胞来源及临床意义。方法建立小鼠单纯疱疹病毒性角膜基质炎(HSK)模型,分别收集正常角膜和感染1型单纯疱疹病毒(HSV-1)后2d、7d、14d的小鼠角膜,行免疫组化染色。在光学显微镜下对免疫组化切片的结果进行分析,观察不同时间点MMP-2、8、9在角膜组织中的定位,并分别统计中央角膜及周边角膜基质中MMP-2、8、9阳性细胞、MMP-2、8、9阳性的中性粒细胞及浸润的中性粒细胞、总细胞的数量,进行统计分析。结果感染后第2天,上述各细胞表达增加,主要位于浅表基质层及上皮下的炎性细胞,周边角膜组织中的中性粒细胞和MMP-2、8、9阳性细胞数明显高于中央角膜基质中;感染后第7天,MMP-2、8、9及中性粒细胞表达下降;感染后第14天可见中央角膜坏死及角膜溃疡形成,同时角膜基质和浸润的炎性细胞中尤其溃疡处,可见MMP-2、8、9表达显著增加。结论 HSV-1感染角膜后,大量中性粒细胞自角膜缘血管网侵入中央角膜基质。中性粒细胞与角膜细胞释放大量的蛋白水解酶(MMP-2、8、9),可能在角膜上皮炎、角膜溃疡穿孔、新生血管形成等过程中发挥重要作用。

Expression and clinical significance of matrix metalloproteinases-2,8,9 positive cells in murine herpes stromal keratitis

Objective By established the mouse model of herpes stromal keratitis（HSK）,to study the expression,distribution and clinical significance of matrix metalloproteinases（MMPs）-2,8,9 positive cells in the corneas of HSK.Methods BALB/c mice infected with herpes simplex virus type-1（HSV-1,KOS strain）to induce HSK.The infected animals were followed up daily with a silt lamp microscope for the development of HSV-1 keratitis.After different time points（0,2,7,14 days after infection）,the animals were killed.The inoculated eyes were enucleated.The samples were analyzed for the distribution of MMP-2,8,9 by immunohistochemistry.Meanwhile,the MMP-2,8,9 positive cells,MMP-2,8,9 positive neutrophils,neutrophils and total cells per high power filed（450）were counted in the central and peripheral corneas.Results At day 2 post-infection,MMP-2,8,9 expression were increased in the epithelium as compared to the uninfected control eyes,and were detected in the superficial stroma and in inflammatory cells beneath the epithelium.The neutrophils and MMP-2,8,9 positive cells in the peripheral stroma are more than these in the center stroma.MMP-2,8,9 and neutrophils expression were decreased at day 7 post-infection.Necrotizing keratitis with corneal ulceration was present on days 14 post-infection.This correlated with increased expression of MMP-2,8,9 within the stroma and in infiltrating inflammatory cells.MMP-2,8,9 staining were particularly intense in the proximity of the ulcers.Conclusions After corneal HSV-1 infection,abundant neutrophils invaded into the stroma cornea through the vascular net of limbus.MMPs produced by inflammatory cells and resident corneal cells play an important role in the pathological process of HSK,possibly promote epithelial keratitis,corneal ulceration and neovascularization after corneal HSV-1 infection.