摘要目的 通过筛选和鉴定HBeAg来源的人类白细胞抗原(HLA)-A0201限制性细胞毒性T淋巴细胞(CTL)表位,为HBeAg表位的特异性治疗性疫苗的开发奠定基础. 方法 选择中国人群最常见的B基因型中的adw血清型的HBV e基因序列,通过网络在线表位筛选服务,分析得到分数比较高,而且是一样的表位,然后采用量化基序方案、延展基序方案以及超基序方案等通用表位筛选原则进行进一步的筛选,得到4条较为理想的九肽(HBe1,HBe2,HBe3,HBe4)作为候选表位.随后借助于流式细胞技术,通过T2细胞实验分析各候选肽以及阳性、阴性、空白对照的荧光系数,从而对所筛选的表位进行体外鉴定.结果 获得的4个候选表位(HBe1:LLWFHISCL ； HBe2:YLVSFGVWI；HBe3:CLTFGRETV ； HBe4:DLLDTASAL)中,HBe2和HBe3的亲和较高； HBe1、HBe2和HBe3的稳定性较好.结论 YLVSFGVWI和CLTFGRETV是HBeAg潜在的HLA-A0201限制性CTL表位,有可能作为HBV慢性感染治疗性DNA疫苗的候选表位.

abstractsObjective To identify HLA-A0201 restricted cytotoxic T lymphocyte (CTL) epitopes derived from the hepatitis B virus e (HBe) antigen,for future use in a specific immunotherapy based on the identified epitope(s).Methods HBe gene sequences from the hepatitis B virus serotypes with the highest frequencies in China were analyzed by bioinformatic web-based interfaces for quantitative motif prediction,extended motif prediction,and peptide super-motif prediction.Four candidate peptides were identified:HBe1,HBe2,HBe3,and HBe4.The affinities of each were tested in vitro with T2 cells,which lack the transporter-associated with antigen transport (TAP) protein but express low levels of the MHC class Ⅰ surface molecule,and measured by the T2 binding assay and DC50 assay.Flow cytometry was used to detect the fluorescence index of control and experimental groups.Results The peptides HBe1 (LLWFHISCL),HBe2 (YLVSFGVWI),HBe3 (CLTFGRETV),and HBe4 (DLLDTASAL) were identified and tested as candidate targets.HBe2 and HBe3 showed higher HLA-A0201 affinity.HBe1,HBe2,and HBe3 showed better binding stability.Conclusion Two peptides based on HBe antigen,YLVSFGVWI and CLTFGRETV,possess both sufficient binding affinity and stability and may represent useful HLA-A0201-restricted CTL epitopes.Further study is needed to determine the immunogenic properties of these two peptides in vivo.