Dempsey P J, Feleppa F P, Brown R W, de Kretser T A, Whitehead R H, Jose D G
J Natl Cancer Inst. 1986 Jul;77(1):1-15.
In an attempt to identify antigens expressed during breast differentiation, three murine monoclonal antibodies, CIBr2, CIBr7, and CIBr18, were produced against the human pleomorphic breast carcinoma cell line PMC42. All three monoclonal antibodies reacted with previously undescribed antigenic determinants on the PMC42 cell line. Antibody CIBr18 reacted only with the immunizing cell line PMC42, whereas antibodies CIBr2 and CIBr7 showed minimal reactivity toward a panel of 34 human leukemia- and solid tumor-derived cell lines. The antigenic determinants detected by the three antibodies were distinct, and each showed variable expression in PMC42 monolayer and organoid cultures. The heterogeneity of staining seen on PMC42 cultures may reflect the fact that this cell line contains up to eight morphologically distinct cell types. Antigen expression correlated with cell type in some instances, whereas in other instances phenotypic subdivision within a cell type was apparent. Antigens recognized by antibodies CIBr7 and CIBr18 were characterized biochemically. In Western blotting, antibody CIBr7 identified a single band of an apparent molecular weight of 38,000 within PMC42 cell lysates. Sodium dodecyl sulfate-polyacrylamide gel analysis of polypeptides immunoprecipitated by antibody CIBr18 from [35S]methionine-labeled PMC42 cell lysates identified two glycoproteins of apparent molecular weights of 115,000 and 120,000, respectively. No biochemical data for the CIBr2 antigen are yet available. All three antigens were detected in human mammary epithelium and some non-breast tissues. The expression of these antigens in normal and neoplastic mammary epithelia is discussed in terms of antigen heterogeneity and changes in antigen expression upon conversion to the malignant state.
为了鉴定乳腺分化过程中表达的抗原，制备了三种针对人多形性乳腺癌细胞系PMC42的鼠单克隆抗体，即CIBr2、CIBr7和CIBr18。这三种单克隆抗体均与PMC42细胞系上以前未描述的抗原决定簇发生反应。抗体CIBr18仅与免疫细胞系PMC42发生反应，而抗体CIBr2和CIBr7对一组34种源自人白血病和实体瘤的细胞系显示出最小反应性。这三种抗体检测到的抗原决定簇各不相同，并且在PMC42单层培养物和类器官培养物中均表现出可变表达。在PMC42培养物上观察到的染色异质性可能反映了该细胞系包含多达八种形态学上不同的细胞类型这一事实。在某些情况下，抗原表达与细胞类型相关，而在其他情况下，细胞类型内的表型细分很明显。对抗体CIBr7和CIBr18识别的抗原进行了生化特性分析。在蛋白质印迹法中，抗体CIBr7在PMC42细胞裂解物中鉴定出一条表观分子量为38,000的单条带。对抗体CIBr18从[35S]甲硫氨酸标记的PMC42细胞裂解物中免疫沉淀的多肽进行十二烷基硫酸钠-聚丙烯酰胺凝胶分析，分别鉴定出两种表观分子量为115,000和120,000的糖蛋白。目前尚无关于CIBr2抗原的生化数据。在人乳腺上皮和一些非乳腺组织中均检测到了这三种抗原。从抗原异质性以及转化为恶性状态后抗原表达的变化方面讨论了这些抗原在正常和肿瘤性乳腺上皮中的表达情况。
