驱动蛋白18B免疫激活表位鉴定及其抗乳腺癌效应验证

Identification of kinesin family member 18B-derived epitope for immune activation and verification of its anti-breast cancer effect

目的从驱动蛋白18B(KIF18B)中寻找具有抗肿瘤免疫效应的细胞毒性T淋巴细胞表位。方法通过癌症基因图谱数据库和免疫组织化学确认KIF18B的表达。利用免疫表位数据库、超基序法、分子操作环境鉴定表位。酶联免疫斑点法、流式细胞术、钙黄绿素释放试验、人源性肿瘤动物模型用于评价表位体内外抗肿瘤免疫活性。秩和检验分析非正态分布变量的组间差异,独立样本t检验比较多次检测结果的组间差异。结果确证KIF18B为乳腺癌抗原,并筛选获得组织相容性抗原A2.1限制性KIF18B表位——KIF18B-P1。KIF18B-P1组CD8+T细胞比例、干扰素-γ分泌水平、靶细胞杀伤率均显著高于阴性肽组[(23.98±1.07)%比(8.81±0.34)%,t=-23.446,P<0.01],其移植瘤体积明显小于阴性肽组[(0.54±0.11)cm3比(0.71±0.09)cm3,t=5.279,P<0.01],差异有统计学意义。结论KIF18B优势表位KIF18B-P1具有体内外抗肿瘤免疫效应。

Objective To isolate the kinesin family member 18B(KIF18B)-derived epitope,which could induce antitumor immunity.Methods KIF18B expression was confirmed by the cancer genome atla database and immunohistochemistry.Immune epitope database,SYFPEITHIP,and Molecular Operating Environment software were used for epitope identification.Enzyme-linked immunospot,flow cytometry,calcein release assay,and a xenograft mouse model were used to examine the immune antitumour activity.Rank-sum test was used to analyze the differences between groups with non-normally distributed variables.Independent-samples t test was used to compare the continuous variable among the different groups.Results The human leukocyte antigen-A2.1-restricted KIF18B-derived epitope KIF18B-P1 was identified.Proportion of CD8+T cells,interferonγsecretion level of CTLs,and killing rate against target cells[(23.98±1.07)%vs.(8.81±0.34)%,t=-23.446,P<0.01]were significantly increased in KIF18B-P1 group as compared with those in negative peptide(NP)group.Similarly,xenograft tumor growth was significantly inhibited in KIF18B-P1 group compared to NP group[(0.54±0.11)cm3 vs.(0.71±0.09)cm3,t=5.279,P<0.01].Conclusion KIF18B-derived CTL epitope KIF18B-P1 could induce anti-tumor immune effects in vitro and in vivo,which might assist clinicians in the development of therapeutic tumor vaccines.