抗上皮细胞黏附分子单克隆抗体的制备及应用’

Preparation and identification of monoclonal antibody specific to the epithelial cell adhesion molecule

目的制备抗人类上皮细胞黏附分子（EpCAM）的单克隆抗体（mAb）并对其进行鉴定及初步功能研究。方法将原核表达的EpCAM免疫BALB／c小鼠，按常规方法将小鼠脾细胞与小鼠骨髓瘤Sp2／0细胞进行融合，用酶联免疫吸附试验进行阳性克隆的筛选。免疫印迹法对制备的mAb进行鉴定，用免疫组织化学法对临床的3份大肠癌组织样本进行初步检测。结果酶联免疫吸附试验筛选获得了3株分泌抗EpCAM的mAb杂交瘤细胞株1810、3G2和4E11。免疫印迹检测结果表明，3株杂交瘤细胞株分泌的抗体均能与EpCAM呈阳性反应，与GST蛋白不发生反应。免疫酶组织化学染色结果显示3株mAb能使3份大肠肿瘤组织样本呈现阳性反应，效果优于对照mAb。结论成功地制备了3株识别大肠癌细胞表面抗原的mAb，这些mAb在大肠癌的诊断中可能具有一定潜在的应用价值。

Objective To prepare and identify the monoclonal antibody （mAb） specific to epithelial cell adhesion molecule （EpCAM） and explore the function of the mAb. Methods The EpCAM antigen expressed by the prokaryotie expression systems was used to immunize the BALB/c mice, and then the splenic cells from the mice were fused with the Sp2/0 cells to produce hybridomas secreting specific mAb. The positive clones were screened by the ELISA. The western blot analysis was used to identify the reactivity of the mAb to the antigen. Then the immunohistochemistry staining was used to detect EpCAM expression in the 3 primary colorectal carcinoma tissues. Results Three mAb specific to EpCAM were obtained by ELISA tests. Western blot results indicated that these three kinds of antibodies could react to the EpCAM antigen, but no response to the GST tag. Immunohistoehemical staining results identified that these mAb could give positive signals to the primary coloreetal carcinoma tissues from patients. Conclusion Three mAb specific to EpCAM are obtained and identified, which contributes to the diagnosis and therapy of the carcinoma in the future.