SOX2抗原HLA-A*0201限制性CTL表位的预测及鉴定  

Prediction and identification of HLA-A*0201 restricted CTL epitopes derived from SOX2 gene family

作　　者：王宇[1] 袁竞妍 张忆雯[1] 杨拴盈[2] WANG Yu;YUAN Jingyan;ZHANG Yiwen;YANG Shuanying(Department of Cardiovascular Surgery,Second Affiliated Hospital of Xi’an Jiaotong University,Xi’an 710004,China;Department of Respiratory and Critical Care Medicine,Second Affiliated Hospital of Xi’an Jiaotong University)

机构地区：[1]西安交通大学第二附属医院心血管外科,西安710004 [2]西安交通大学第二附属医院呼吸与危重症医学科

出　　处：《山西医科大学学报》2020年第1期58-64,共7页Journal of Shanxi Medical University

基　　金：国家自然科学基金面上项目(81672300)。

摘　　要：目的 预测和鉴定SOX2抗原的HLA-A*0201限制性CTL表位,通过体外实验筛选出能诱导机体特异性杀伤肺癌肿瘤细胞的抗原表位。方法 应用生物信息学软件SYFPEITHI、BIMAS、ProPred-I对SOX2蛋白进行优势表位的预测和筛选。通过T2细胞结合实验检测不同多肽组在不同肽浓度条件下HLA-A2分子平均荧光强度增加百分数(%MFI increase)来考察表位肽与MHCⅠ类分子的结合力强弱;用优势表位肽诱导PBMCs、T2细胞分别产生效应细胞和靶细胞,通过hIFN-γELISPOT实验检测IFN-γ斑点数、LDH释放实验检测光密度(OD)值来考察效应细胞对靶细胞的杀伤力。结果 预测所得优势表位肽:SMYLPGAEV、TLMKKDKYT、ALGSMGSVV。随着表位肽浓度的增高,SMYLPGAEV组平均荧光强度增加百分数逐渐升高,当肽浓度为50μmol/L和100μmol/L时明显高于TLMKKDKYT、ALGSMGSVV、阳性肽和阴性肽组,差异具有统计学意义(P<0.05)。LDH释放实验结果显示表位肽SMYLPGAEV、TLMKKDKYT组的OD值高于其他肽组,差异具有统计学意义(P<0.05)。hIFN-γELISPOT实验结果显示表位肽SMYLPGAEV诱导的CTLs较另两种表位肽诱导的CTLs能产生更多的IFN-γ斑点,差异具有统计学意义(P<0.05)。结论 在SOX2抗原的众多天然表位肽中,SMYLPGAEV具有较强免疫原性,有望用于制备肺癌治疗性疫苗。Objective To predict and identify the HLA-A0201 restricted CTL epitopes of SOX2 protein antigen,and screen the epitope peptide with strongest ability that can induce the human body to specifically kill the lung cancer cells by a series of tests in vitro.Methods The dominant epitopes of SOX2 antigen were predicted and screened by SYFPEITHI,BIMAS,and ProPred-I.Percentages of the median fluorescence intensity increase(%MFI increase)of each epitope peptide in different concentrations was detected by T2 binding assay,and then the binding ability between each epitope peptide and MHCⅠmolecules was obtained.The effector cells were acquired by inducing PBMCs with peptides,and the target cells were acquired by inducing T2 cells with peptides.Then the cytotoxic activity of effector cells was detected by measuring the number of IFN-γspots in hIFN-γELISPOT test and the optical density(OD)in LDH test.Results The dominant epitopes acquired by softwares were SMYLPGAEV,TLMKKDKYT and ALGSMGSVV.In SMYLPGAEV group,the%MFI increase increased along with the increase of the peptide concentrations.When the concentration of SMYLPGAEV peptide was 50μmol/L or 100μmol/L,the%MFI increase was significantly higher than that in the other peptide groups(P<0.05).The LDH releasing test showed that OD was significantly higher in SMYLPGAEV group and TLMKKDKYT group than in the other peptide groups(P<0.05).The hIFN-ELISPOT test showed that IFN-γspots secreted by SMYLPGAEV were more than that by TLMKKDKYT and ALGSMGSVV(P<0.05).Conclusion SMYLPGAEV is the HLA-A*0201 restricted CTL natural epitope of SOX2 antigen that may induce the patients to have strongest immune responses to lung cancer,and this peptide may play an important role in lung cancer vaccine.

关 键 词：肺癌 SOX2 表位预测 表位鉴定 疫苗 

分 类 号：R734.2[医药卫生—肿瘤]