T细胞受体β独特型抗原决定簇DNA疫苗诱导抗淋巴瘤抗体的研究

Experimental study on TCRβ idiotypic antigenic determinants DNA vaccine to induce anti-lymphoma antibodies

目的 观察T细胞受体 (TCR) β不同独特型抗原决定簇DNA疫苗诱导BALB c小鼠抗人类CEM淋巴瘤细胞免疫反应的情况。方法 RT PCR扩增CEM细胞特异性重排的TCRβ基因片段 ,克隆至真核表达载体pcDNA3中 ,然后以此为模板 ,扩增编码不同抗原决定簇的基因片段 ,分别克隆到pcDNA3中作为DNA疫苗。肌肉注射法免疫小鼠 ,间接免疫荧光法检测小鼠血清中抗体生成情况。结果 CEM细胞TCRβ共包含 5个抗原决定簇 ,其DNA疫苗免疫的 6只小鼠全部产生了特异性抗独特型抗体 (最高滴度 1∶480 ) ;含 4个抗原决定簇的DNA疫苗免疫的 6只小鼠中有 4只产生了特异性抗独特型抗体 ,但滴度均较低 (最高滴度 1∶80 ) ;仅含 2个抗原决定簇的DNA疫苗未能使小鼠产生特异性抗独特型抗体。结论 包含TCRβV区全长 ,共有 5个抗原决定簇的独特型DNA疫苗可以诱导小鼠产生抗淋巴瘤细胞的独特型特异性抗体 ;含有 4个抗原决定簇的DNA疫苗仍可诱导特异性抗体的生成 ,但这种反应较弱 ;而仅含有

Objective To investigate the anti-human CEM lymphoma cell activities induced by TCR idiotypic DNA vaccine containing different antigen determinants in BALB/c mice. Methods The specific rearranged gene fragment encoding TCRVβ region of CEM cell line was obtained by RT-PCR technique. The PCR product was cloned into eukaryocytic expression vector pcDNA3,which was used as DNA vaccine and template for PCR amplifying different antigen determinant. Gene fragments encoding different antigen determinant were amplified and cloned into pcDNA3, separately. The experimental mice were immunized by intramuscular injection of the DNA vaccines. The specific anti-idiotype antibodies were detected by indirect immunofluorescence assay. Results TCRβV of CEM cell line contains five antigen determinants. Specific anti-idiotype antibody was detected in all of the six mice immunized with DNA vaccine containing all the five determinants (the highest titer was 1∶480). Although the antibody could also be detected in four of the six mice immunized with DNA vaccine containing four of the five antigen determinants, the antibody titer was lower (the highest titer was 1∶80). DNA vaccine containing two of the five determinants could not induce the specific antibody. Conclusion The idiotypic DNA vaccine containing the whole TCRβV five antigen determinants could induce the specific anti-lymphoma idiotypic antibody in BALB/c mice.