摘要
目的 克隆能与多种肿瘤细胞特异性地反应 ,且经核素标记已成功试用于肿瘤原发灶和转移灶的临床显像的单克隆抗体 (McAb) 3H11的对应抗原 ,研究其表达分布。方法 在用McAb3H11筛选胃癌细胞MGC 80 3cDNA表达文库 ,获得一段阳性cDNA片段的基础上 ,用cDNA末端快速克隆技术 (RACE)获得对应抗原的全长cDNA。Northernblot研究表达分布。结果 McAb 3H11抗原cDNA长 2 .2kb ,主要分布于肿瘤组织。经序列比较在GenBank中无高度同源基因。同时在制备抗体的过程中发现McAb 3H11抗原在哺乳类体内免疫原性较低。结论 McAb 3H11对应抗原可能是哺乳动物胚胎生长的调节蛋白 ,在肿瘤中恢复表达 ,可能与细胞快速增殖和低分化相关。
Objective Monoclonal antibody (McAb) 3H11 can specifically bind to different cancer cells from different tissues. Meanwhile, McAb 3H11 labeled with radioactive isotopes has been successfully applied to detect primary cancer and metastatic cancer in clinical imaging. Molecular cloning of the antigen recognized by McAb 3H11 will be significant for understanding tumor development. Methods Based on the fragment of the McAb 3H11 antigen cloned by Immunoscreening MGC803 cDNA expression library, the whole length of the cDNA molecule was gotten by RACE and nested PCR. Results Sequence data of the cDNA molecule indicates that there was no homologous gene in GenBank. Northern blot experiments showed that mRNA of McAb 3H11 antigen extensively distributes in different cancer cells and tissues but not in corresponding normal tissues. Moreover in producing antibodies of the antigen expressed prokaryotically, it was found that the immunogenicity of the antigen was quite low in mammalian. Conclusion The antigen recognized by McAb 3H11 acts as a regulator in embryo cells and regains expression in tumor cells; and it may be associated with low differentiation and high proliferation.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2001年第3期154-157,共4页
National Medical Journal of China
基金
国家八六三高科技研究发展计划基金资助项目! (10 2 10 0 1 0 8)
北京市肿瘤分子生物学实验室基金资助项目
关键词
单克隆抗体
抗原
肿瘤
分子克隆
基因表达
对应抗原
Antibody, monoclonal
Antigens, neoplasm
Cloning molecular cloning
Gene expression
