人乳头瘤病毒16E7_(49-57)的分子修饰与鉴定

Molecular Modification and Identification of HPV16E749-57

目的对人乳头瘤病毒(HPV)16型E7抗原的人白细胞抗原A2分子限制性细胞毒性T细胞表位HPV16E749-57进行氨基酸置换修饰,并鉴定修饰表位。方法运用量化模体方案对置换后的多肽与人白细胞抗原A2分子的结合系数进行比较,以分子模拟方法确定合成序列,采用标准Fmoc方案进行合成与纯化多肽以及乳酸脱氢酶释放法检测特异性细胞毒性T细胞诱导活性。结果修饰多肽符合人白细胞抗原A2分子限制性细胞毒性T细胞的表位要求,9肽RLHYNIVTF具有特异性细胞毒性T细胞诱导活性。结论修饰表位(氨基酸序列RLHYNIVTF)具有更好的结合力和较强的抗原性,可以代替原有序列E749-57(氨基酸序列RAHYNIVTF)作为人乳头瘤病毒感染治疗性肽疫苗分子设计的候选表位。

Objective To introduce the amino acid substitution for HP V16E749-57(HLA-A2-restricted CTL epitope) and to identify the novel epitopes.Me thods Quantitative method was used to evaluate the affinity of the substituted peptides.To determine the peptide candidates to be synthesized and identified,the molecular models of the HLA-A2-peptide complex and CTL epitope candidates b ound to the HLA-A2 molecule were established by computer molecular modeling.Pep tides were synthesized and purified with standard Fmoc assay,lactate dehydrogen ase (LDH) release assay was used to determine their abilities of inducing the ge neration of specific CTLs.Results Modified peptides met the requirements of H LA-A2-restricted CTL epitopes.Peptide RLHYNIVTF had the abilitiy of inducing th e generation of specific CTLs.Conclusions Compared with HPV17E749-57 the mod ified peptide RLHYNIVTF has a higher antigenicity and affinity to HLA-A2.So,pe ptide RLHYNIVTF may be used as one of the HLA-A2-restricted candidate epitopes,instead of HPV17E749-57,for peptide vaccine in the treatment of HPV infection.