A decaepitope polypeptide primes for multiple CD8+ IFN-γ and Th lymphocyte responses:: Evaluation of multiepitope polypeptides as a mode for vaccine delivery
A decaepitope polypeptide primes for multiple CD8+ IFN-γ and Th lymphocyte responses:: Evaluation of multiepitope polypeptides as a mode for vaccine delivery
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DOI：
10.4049/jimmunol.168.12.6189
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发表时间：
2002-06-15
影响因子：
4.4
通讯作者：
Sette, A
中科院分区：
文献类型：
--
作者：
Alexander, J;Oseroff, C;Sette, A
蛋白质通常被认为是CTL应答的无效免疫原。我们合成了一个100聚体的十表位多肽，并在HLA转基因小鼠中测试了其诱导多种CD 8（+）IFN-γ和Th淋巴细胞（HTL）应答的能力。在不存在佐剂的情况下进行单次免疫后，对于构建体中包括的所有表位（六个A2.1-、三个All限制性CTL表位和一个通用HTL表位）检测到显著的IFN-γ体外回忆应答。使用截短形式的十表位多肽进行免疫以证明最佳免疫原性与至少30-40个残基（3-4个表位）的大小相关。截短构建体的溶解度分析用于鉴定IFN-γ应答的免疫原性与这些构建体形成颗粒聚集体的倾向之间的相关性。虽然十表位多肽和IFA中乳化的表位库使用新鲜脾细胞引起类似水平的CD 8（+）应答，但我们发现十表位多肽更有效地引发体外回忆CD 8（+）T细胞应答。最后，还在十表位多肽和通过裸DNA免疫递送的编码相同多肽的相应基因之间进行免疫原性比较。尽管裸DNA免疫在单次免疫后2周诱导了更大的直接离体和体外回忆反应，但仅多肽在引发免疫后6周诱导了显著的体外回忆反应。这些研究支持进一步评价多表位多肽疫苗诱导CD 8（+）IFN-γ和HTL应答。
Proteins are generally regarded as ineffective immunogens for CTL responses. We synthesized a 100-mer decaepitope polypeptide and tested its capacity to induce multiple CD8(+) IFN-gamma and Th lymphocyte (HTL) responses in HLA transgenic mice. Following a single immunization in the absence of adjuvant, significant IFN-gamma in vitro recall responses were detected for all epitopes included in the construct (six A2.1-, three All-restricted CTL epitopes, and one universal HTL epitope). Immunization with truncated forms of the decaepitope polypeptide was used to demonstrate that optimal immunogenicity was associated with a size of at least 30-40 residues (3-4 epitopes). Solubility analyses of the truncated constructs were used to identify a correlation between immunogenicity for IFN-gamma responses and the propensity of these constructs to form particulate aggregates. Although the decaepitope polypeptide and a pool of epitopes emulsified in IFA elicited similar levels of CD8(+) responses using fresh splenocytes, we found that the decaepitope polypeptide more effectively primed for in vitro recall CD8(+) T cell responses. Finally, immunogenicity comparisons were also made between the decaepitope polypeptide and a corresponding gene encoding the same polypeptide delivered by naked DNA immunization. Although naked DNA immunization induced somewhat greater direct ex vivo and in vitro recall responses 2 wk after a single immunization, only the polypeptide induced significant in vitro recall responses 6 wk following the priming immunization. These studies support further evaluation of multiepitope polypeptide vaccines for induction of CD8(+) IFN-gamma and HTL responses.