正常角膜与圆锥角膜中的Ⅰ型、Ⅵ型胶原与金属蛋白酶-2

摘要

目的对比正常角膜与圆锥角膜中的Ⅰ型，Ⅵ型胶原及金属蛋白酶-2的定位与含量。方法应用酶免疫组化及间接免疫荧光技术检测正常与圆锥角膜中Ⅰ型、Ⅵ型胶原及金属蛋白酶-2（MMP-2)的定位。阳性结果应用图像分析系统进行定量分析。结果免疫组化结果显示所有角膜中Ⅰ型胶原存在于前弹力层和基质中；Ⅵ型胶原存在于上皮基底膜、前弹力层、基质、后弹力层；MMP-2存在于上皮、基质、内皮中。同正常角膜比，圆锥角膜中Ⅰ型、Ⅵ型胶原的含量无差别而MMP-2的含量明显增多，差异有显著性。结论圆锥角膜的MMP-2含量增多，其所导致的胶原降解异常可能是圆锥角膜发病的关键。%ObjectiveTo compare the levels and locations of metalloprotionase-2（MMP-2），collagen types Ⅰ and Ⅵ in keratoconus and normal human corneas．MethodsAn immunoperoxidase and indirect immunofluorescent technique were used to visualize the presence of collagen types Ⅰ， Ⅵ and MMP-2．The immunohistochemical staining was further analyzed and the intensity of reaction products was measured with an Image-processing system．ResultsCollagen type Ⅰ was demonstrated immunohistochemicall and indirect immunofluorescent technique in the bowman and stroma layers；collagen type Ⅵ was in epithelium basement，bowman，stroma and descement layers；MMP-2 was in epithelium，stroma and endothelium of all corneal sections．Compared with normal control specimens，the staining intensity of collagen types Ⅰ and Ⅵ was similar，while MMP-2 was markly increased．ConclusionsKeratoconus contained an increased level of MMP-2 and similar of collagen levels．These results lead further support to the hypothesis that degradation processes may be aberrant in keratoconus．