恶性疟细胞毒性T淋巴细胞单表位疫苗抗原递呈细胞模型的建立

Establishment of Antigen Presenting Cells Model of Plasmodium Falciparum Cytotoxic T Lymphocyte Single Epitope Vaccine

目的 构建恶性疟细胞毒性T淋巴细胞（cytotoxic T lymphocyte，CTL）单表位疫苗及建立抗原递呈细胞模型。方法一采用中国人群常见的HLAⅠ类分子A11限制的恶性疟CTL抗原表位（VTCGNGIQVR），合成其DNA序列并克隆于真核表达载体，构建CTL单表位DNA疫苗。将上述克隆在HLA-A11表型细胞株中进行表达，流式细胞仪检测细胞表面HLAⅠ类分子表达水平。结果 上述CTL单表位DNA疫苗编码的短肽在细胞内的表达明显促进HLA-A11分子在细胞表面的表达，用流式细胞仪测定平均荧光强度可量化表达水平(P ＜ 0．05)。结论 成功构建CTL单表位短肽表达载体，模拟体内环境建立了抗原递呈细胞模型，提示CTL表位在该细胞模型内被内源性加工和递呈，以该表位为基础的疫苗可以为HLA-A11遗传背景的人群提供免疫防护。

Objective To construct plasmodium falciparum cytotoxic T lymphocyte（CTL） single epitope vaccine and establish antigen presenting cells model． Methods Gene encoding HLA-A11 restricted plasmodium falciparum CTL epitope (VTCGNGIQVR), which was in high frequency among Chinese population, was chosen and cloned into an eukaryotic expressing vector to form CTL single epitope vaccine: pcDNA3．1/β2m/A11． This plasmid was transfected and expressed in cell lines bearing only HLA-A11 molecule． The expressions of HLA class I molecules were accessed by flow cytometry． Results The CTL single epitope was expressed in HLA-A11 cell lines and an obviously increased expressions of HLA class were detected in the transfected cell lines，and evaluated as mean channel number of fluorescence by flow cytometry (P ＜ 0．05)． Conclutions CTL single epitope expressing plasmid was constructed and the antigen presenting cells model was established． It was demonstrated that plasmodium falciparum CTL single epitope was effectively processed and expressed． Our work suggested the single-epitope vaccine might provide protection for populations which containing HLA-A11 background．