Keene W E, Hidalgo M E, Orozco E, McKerrow J H
Department of Pathology, University of California, San Francisco 94143.
Exp Parasitol. 1990 Aug;71(2):199-206. doi: 10.1016/0014-4894(90)90022-5.
Work from several laboratories suggests a correlation between expression of cysteine proteinase activity and the cytopathic effect of virulent HM1 strain Entamoeba histolytica trophozoites on cultured cell monolayers. Consistent with this relationship, we find that L-6 trophozoites, mutants cloned from the HM1 parent strain, are deficient in both proteinase expression and cytopathic effect. Three other clones, with proteinase expression equal to or greater than that of the HM1 strain, express the cytopathic effect. Furthermore, a nontoxic specific proteinase inhibitor, Z-phenylalanyl-alanyl-CH2F, inhibits the cytopathic effect of live trophozoites in a dose-dependent manner. These results support the hypothesis that expression and release of the cysteine proteinase is an important factor in producing the cytopathic effect, presumably by its degradation of cell anchoring proteins.
来自多个实验室的研究表明，半胱氨酸蛋白酶活性的表达与致病的溶组织内阿米巴滋养体HM1株对培养细胞单层的细胞病变效应之间存在相关性。与这种关系一致的是，我们发现从HM1亲本菌株克隆的L-6滋养体在蛋白酶表达和细胞病变效应方面均存在缺陷。另外三个克隆，其蛋白酶表达等于或高于HM1菌株，表现出细胞病变效应。此外，一种无毒的特异性蛋白酶抑制剂Z-苯丙氨酰-丙氨酰-CH2F以剂量依赖的方式抑制活滋养体的细胞病变效应。这些结果支持了这样一种假说，即半胱氨酸蛋白酶的表达和释放是产生细胞病变效应的一个重要因素，可能是通过其对细胞锚定蛋白的降解作用。
