目的：采用生物信息方法预测和鉴定survivin抗原HLAA2+限制性CTL表位，为探索基于survivin的肿瘤免疫治疗奠定基础。〖HT5W〗方法：〖HT5"SS〗采用超基序法和量化基序法对靶抗原survivin HLAA2+限制性 CTL表位进行预测；选取得分>10的表位肽为候选对象，并进行人工合成。采用T2细胞，以HLAA2结合实验和流式细胞术（FITC染色）检测候选CTL表位肽的结合亲和力\[以荧光系数（fluorescence index,FI）表示\]；以HLAA2解离实验和流式细胞术检测其结合稳定性\[以复合物解离50%的时间DC50（dissociation complex 50%）表示\]。〖HT5W〗结果：〖HT5"SS〗预测到的候选survivin CTL表位肽分别是：20STFKNWPFL28 (SV2028)、23KNWPFLEGC31 (SV2331)、96LTLGEFLKL104 (SV96104)、6LPPAWQPFL14 (SV614)、33CTPERMAEA41 (SV3341)、46CPTENEPDL54 (SV4654)、130KVRRAIEQL138 (SV130138)、37RMAEAGFIH45 (SV3745)、88SVKKQFEEL96 (SV8896)。亲和力分析显示： SV2028 、SV96104、SV130138、SV2331的FI分别为8.61、6.88、5.89、3.81；SV3341、SV614、 SV4654、 SV3745 、SV8896的FI分别为0.31、-0.29、-04、-0.16和-0.03；稳定性分析结果DC50为：SV2028、SV96104、SV130138 ＞8 h；SV2331 为4~6 h；SV614、SV3341、SV8896为2~4 h；SV4654、 SV3745为0~2 h。结果提示,SV2028 、 SV96104、SV130138为高亲和力表位肽，SV2331为中等亲和力表位肽，SV3341、SV614、 SV4654、 SV3745 、SV8896为低亲和力表位肽。〖HT5W〗结论：〖HT5"SS〗超基序法、量化基序法可快速有效地预测抗原表位，SV2028 、SV96104、SV130138有可能是survivin HLAA2+ CTL表位，可用于后续研究。

Objective: To predict and identify survivin specific HLAA2+ CTL restricted epitopes by bioinformatic methods, so as to provide a foundation for survivinbased immunotherapy. Methods: Survivin specific HLAA2+ restricted CTL epotides were predicted by computer supermotif algorithm combined with quantitativemotif algorithm. Candidate epitopes were verified when their scores were higher than 10 and were then artificially synthesized. Affinity of candidate epitope was examined by HLAA2 binding assay combined with flow cytometry using T2 cells (shown as fluorescence index, FI). Stability of candidate epitope was evaluated by HLAA2 dissociation assay combined with flow cytometry (shown as 50% complex dissociation time, DC50). Results: Nine candidate epotides were obtained: 20STFKNWPFL28 (SV2028), 23KNWPFLEGC31 (SV2331), 96LTLGEFLKL104 (SV96104), 6LPPAWQPFL14 (SV614), 33CTPERMAEA41 (SV3341), 46CPTENEPDL54 (SV4654), 130KVRRAIEQL138(SV130138), 37RMAEAGFIH45(SV3745), and 88SVKKQFEEL96 (SV8896). HLAA2 binding assay showed that FI values of SV2028, SV96104, SV130138 and SV2331 epotides were 8.61, 688, 5.89 and 3.81, respectively; those of SV3341, SV614, SV4654, SV3745 and SV8896 epotides were 0.31, -0.29,-04,-0.16 and -0.03, respectively. HLAA2 dissociation assay showed that DC50 values of SV2028, SV96104 and SV130138 epotides were longer than 8 h; that of SV2331 epotide was 46 h; those of SV614, SV3341and SV8896 epotides were all 24 h; those of SV4654, SV3745 epotides were both 02 h. The above results demonstrated that SV2028, SV96104 and SV130138 were high affinity epotides; SV2331 was intermediate affinity epotide; and SV3341, SV614, SV4654, SV3745 and SV8896 were low affinity epotides. Conclusion: Antigen epitope can be quickly and efficiently predicted by supermotif algorithm combined with quantitativemotif algorithm. SV2028, SV96104 and SV130138 epitopes are survivin specific HLAA2+ restricted CTL epotides, which can be used for later research.

福建省科技发展计划重点项目（No.2008I0012)