Chen Y F, Haskill S
Cancer Res. 1984 Oct;44(10):4548-52.
Immunodiffusion, immunofluorescence, and flow cytometric techniques were used to characterize the expression of murine gamma-glutamyltranspeptidase (gamma GT) on normal and cervical cancer tissue. In immunodiffusion tests, the rabbit antiserum produced against highly purified murine kidney gamma GT formed two lines against normal kidney and one line with pancreas which fused with the major line of kidney. gamma GT purified by similar techniques from a murine cervical tumor produced a single line of identity with the kidney preparation, indicating that the gamma GT of the tumor was immunologically identical with normal enzyme. Both kidney and tumor gamma GT were labile to heating at 56 degrees, and neither enzyme was protected by dithiothreitol. Polyacrylamide gel electrophoresis indicated three components from the tumor material and four from the normal kidney. Both tissue sites expressed several isozymes which appeared to be antigenically identical. Biochemical methods indicated there was at least 50-fold more gamma GT in kidney than in tumor cells. In contrast, the level of membrane-associated gamma GT determined by flow cytometry was similar in the two cell types. Two-parameter flow cytometric analysis with DNA and antibody defined the presence of two proliferating gamma GT-positive tumor cell populations in the cervical tumor. Thus, although tumor and normal gamma GT are antigenically identical, the antisera can be combined with DNA and other markers to better describe tumor heterogeneity and progression.
采用免疫扩散、免疫荧光和流式细胞术技术来表征小鼠γ-谷氨酰转肽酶（γGT）在正常组织和宫颈癌组织中的表达。在免疫扩散试验中，针对高度纯化的小鼠肾γGT产生的兔抗血清与正常肾形成两条沉淀线，与胰腺形成一条沉淀线，该沉淀线与肾的主要沉淀线融合。用类似技术从鼠宫颈癌中纯化得到的γGT与肾制剂产生一条单一的同一沉淀线，表明肿瘤的γGT在免疫学上与正常酶相同。肾和肿瘤的γGT在56摄氏度加热时均不稳定，且两种酶均不受二硫苏糖醇的保护。聚丙烯酰胺凝胶电泳显示肿瘤材料中有三种成分，正常肾中有四种成分。两个组织部位均表达了几种似乎在抗原性上相同的同工酶。生化方法表明，肾中的γGT含量至少比肿瘤细胞高50倍。相比之下，通过流式细胞术测定的两种细胞类型中膜相关γGT的水平相似。用DNA和抗体进行的双参数流式细胞术分析确定了宫颈癌中有两个增殖的γGT阳性肿瘤细胞群体。因此，尽管肿瘤和正常γGT在抗原性上相同，但抗血清可与DNA和其他标记物结合，以更好地描述肿瘤的异质性和进展情况。
