乳链菌肿瘤特异性标记载体的构建及初步验证  

Construction and identification of the tumor-specific imaging system with the recombinant lactococcus lacti shuttle vector

作　　者：陈雅莹 陈科全 陈学清 

机构地区：[1]广州医学大学附属第一医院消化内科,510120

出　　处：《现代消化及介入诊疗》2014年第4期214-217,共4页Modern Interventional Diagnosis and Treatment in Gastroenterology

基　　金：国家自然科学基金项目(No:81250012)

摘　　要：目的利用乳链菌穿梭载体构建肿瘤特异标记表达系统,为肿瘤特异性口服疫苗的研究开辟一个新领域。方法采用体外基因拼装的方法得到PEG-3启动子,经酶切鉴定并测序验证。然后利用基因克隆技术,将PEG-3启动子、EGFP、Poly A亚克隆到乳链菌载体pTRKH2中,成功得到肿瘤特异标记质粒pTR-peg3-egfp。最后,转染肿瘤及非肿瘤细胞初步验证其肿瘤特异性标记能力。结果通过PCR基因拼装得到460bp左右目的片段,测序结果与设计完全一致。获得了肿瘤特异标记的乳链菌穿梭质粒pTR-peg3-egfp,并在细胞水平得到初步验证。结论 PEG-3启动子介导的乳链菌穿梭质粒具有肿瘤特异性,这一实用新颖的系统将为研究乳链菌疫苗应用于肿瘤标记及靶向治疗奠定基础。Objective The aim of this study is to construct a tumor-specific imaging system with the shuttle vector of lactococcus lacti which will open a new field for the study of tumor-specific oral vaccine. Methods The PEG-3 promoter was constructed by means of PCR base gene assembly, and conformed by en-zyme digestion and DNA sequencing. Then, constructed recombinant pTR-peg3-egfp （shuttle plasmid） carry-ing the PEG-3 promoter enhanced green fluorescent protein and Poly A tail. Finally, the ability of tumor-spe-cific imaging in the means of in vitro transfection was validated. Results A 460 bp purpose fragment obtained by PCR gene splicing agreed exactly with the design. The tumor specific lactococcus lacti plasmid pTR-peg3-egfp was successfully constructed , and also got a preliminary validation on cellular level. Conclusion Lacto-coccus lacti vector with PEG-3 promoter could specifically recognize tumor cell. This utility, new lactococ-cus lacti system can lay a solid foundation for both cancer imaging and tumor-specific gene therapy.

关 键 词：PEG-3启动子 乳链菌 基因治疗 肿瘤 

分 类 号：R730.54[医药卫生—肿瘤]