Zhai Hua-lei, Xie Li-xin, Dong Xiao-guang
State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Qingdao 266071, China.
Zhonghua Yan Ke Za Zhi. 2007 Sep;43(9):817-22.
To study the roles of gelatinases, including matrix metalloproteinase (MMP)-2 and MMP-9, in pathological changes of fungal keratitis in rabbits.
Eighty New Zealand albino rabbits were randomly and equally divided into 4 groups, 3 of them were test groups, with Fusarium solani, Aspergillus fumigatus, and Candida albicans inoculated onto the right corneas, respectively. In the other group, sterile saline was injected onto the right corneas and was used as the control group. The source and activity of gelatinases were examined by immunohistochemistry and gelatin zymography, respectively. Hematoxylin-eosin stains was applied for observing infiltration of inflammatory cells and degradation of corneal extracellular matrixes (ECMs). Periodic acid-Schiff stain was used for studying hyphal growth patterns and the invasive depth in the cornea.
MMP-2 was mainly produced by the keratocytes. Active MMP-2 was detected from day 5 after inoculation and increased greatly on day 8. MMP-9 was mostly produced by neutrophils, and active MMP-9 was detected from day 1 and increased to day 3, then decreased gradually. In A. fumigatus and C. albicans keratitis, the corneal ECMs were degraded obviously, the hyphae grew vertically, and the neutrophils were much more than those in F. solani keratitis whose hyphae grew horizontally and ECMs were degraded slightly. On day 8, the hyphae and neutrophils in F. solani and C. albicans keratitis decreased greatly compared with day 3, but did not change significantly in A. fumigatus keratitis.
There is significant difference in gelatinase activities in the rabbits' corneas infected by F. solani, A. fumigatus, and C. albicans. Gelatinases play important roles in the degradation of corneal ECMs. Hyphal growth pattern and invasive depth are depended on the difference of degradations of ECMs and show difference in various fungal keratitis.
研究明胶酶，包括基质金属蛋白酶（MMP）-2和MMP-9，在兔真菌性角膜炎病理变化中的作用。
80只新西兰白兔随机等分为4组，其中3组为试验组，分别将茄病镰刀菌、烟曲霉和白色念珠菌接种于右眼角膜。另一组右眼角膜注射无菌生理盐水作为对照组。分别采用免疫组织化学和明胶酶谱法检测明胶酶的来源和活性。应用苏木精-伊红染色观察炎性细胞浸润及角膜细胞外基质（ECM）的降解情况。采用高碘酸-希夫染色研究菌丝生长模式及在角膜中的侵袭深度。
MMP-2主要由角膜细胞产生。接种后第5天可检测到活性MMP-2，第8天显著增加。MMP-9主要由中性粒细胞产生，接种后第1天可检测到活性MMP-9，第3天增加，随后逐渐下降。在烟曲霉和白色念珠菌性角膜炎中，角膜ECM明显降解，菌丝垂直生长，中性粒细胞比茄病镰刀菌性角膜炎中的多，后者菌丝水平生长，ECM降解轻微。第8天，与第3天相比，茄病镰刀菌和白色念珠菌性角膜炎中的菌丝和中性粒细胞显著减少，但烟曲霉性角膜炎中无明显变化。
茄病镰刀菌、烟曲霉和白色念珠菌感染兔角膜后，明胶酶活性存在显著差异。明胶酶在角膜ECM降解中起重要作用。菌丝生长模式和侵袭深度取决于ECM降解的差异，在不同真菌性角膜炎中表现不同。
