癌胚抗原DNA疫苗对大肠癌特异性细胞免疫的激活效果

目的检测以质粒pIRES为载体构建的带有全序列癌胚抗原(CEA)基因的核苷酸疫苗对机体特异性抗肿瘤免疫反应的激活效果。方法将CEA基因片段连接于真核表达质粒pIRES中,用肌肉注射方法接种核酸疫苗;检测CEA在小鼠肌肉组织中的表达情况及其对小鼠脾细胞CEA特异性细胞免疫反应的激活效果。结果小鼠经肌肉注射质粒后,免疫组化证实该核酸疫苗可在体内有效表达CEA;分子免疫检测显示注射后小鼠特异性淋巴细胞增值反应明显并且伴有自然杀伤细胞NK活性显著增高。结论实验所构建的核酸疫苗pIRESCEA可在体外及小鼠体内高效表达并表现出良好的细胞免疫原性。

CEA cDNA vaccine induces special cellular immune response to a carcinoembryonic antigen in mice

Objective To detect the expression of the DNA vaccine in mice muscles and identify it's ability to induce special cellular immune r esponse to carcinoembryonic antigens. Methods Using cloning technique,the cDNA fragments of CEA gene were constructed into the mammalian co-expression plasmid vector pIRES. Mice's tongue muscle were injected with the constructed plasmid. The expression of CEA molecules in muscle were determined by immunohistochemitry technique and the special celluar immuse responses were detected by CTL and NK cytotoxity assays. Results We showed that plasmids could express the CEA molecules in mice's tongue muscles by immunohistochemitry technique.CTL activities and NK cytotoxity were much stronger in immunized mice. Conclusions The constructed mammalian co-expression plasmid pIRES-CEA can express CEA molecules in muscles and can generate cellular immunological responses against CEA positive carcinoma.