中文摘要：

目的：分析结核分枝杆菌（MTB）抗原Rv2389的T细胞表位,确定和筛选优势表位,为研制更加有效的诊断标志物,和更安全、高效的表位疫苗奠定基础。方法：应用在线预测软件IEDB和SYFPEITHI对MTB抗原Rv2389的T细胞表位进行预测,并与ESAT-6相比较;采用SOPMA Sever软件预测其编码蛋白的二级结构;用Ex PASy在线软件预测Rv2389的三级结构,综合分析Rv2389的T细胞抗原决定簇。结果：经软件分析,Rv2389多肽预测分值普遍高于ESAT-6,Rv2389分值较高的T细胞表位区域氨基酸位于35~43、85~93、107~126和184~200。MTB抗原Rv2389蛋白无规则卷曲占71.89%,β折叠占5.53%,主要覆盖的氨基酸区域位14~23,51~67,72~112,117~127和134~212。说明这些肽段存在潜在的抗原表位优势区域的可能性;三级结构预测显示,85~93位氨基酸和107~126位氨基酸暴露于蛋白表面,是最有可能的抗原表位。结论：经生物信息学软件预测MTB抗原Rv2389有2个T细胞优势表位,即85~93位和107~126位氨基酸。

英文摘要：

Objective： Determine and screen the T cell dominant epitopes of Mycobacterium tuberculosis antigen Rv2389 （MTB）, and so to lay the foundation of developing more effective diagnostic markers, and producing much safer and more efficient epitope vaccine. Methods： We predicted and compared the T cell epitopes of MTB antigen of Rv2389 and ESAT-6 with application of on-line prediction software IEDB and SYFPEITHI. The protein secondary structure was predicted by using the SOPMA Sever software. The tertiary structure of Rv2389 was predicted and comprehensively analyzed by online software ExPASy. Results： Through the analysis of the software, prediction score of Rv2389 was higher than that of ESAT-6. T cell epitope regions with high score of Rv2389 were in 35-43, 85-93, 107-126 and 184-200. Random coil in Rv2389 protein of MTB antigen accounted for 71.89%, beta folding accounted for 5.53%, and mainly covered the region of 14-23,51-67,72-112,117-127 and 134-212, which illustrated the possibility of potential antigen epitope of the Mycobacterium tuberculosis antigen. The prediction of tertiary structure displayed that amino acids regions of 85-93 and 107-126 exposed on the surface of the protein and had more possibility to be antigen epitopes. Conclusion： Two possible T cell dominant epitopes （85-93 and 107-126） in Rv2389 antigen of Mycobacterium tuberculosis were determined by bioinformatics sottwares.