Lau Yuk Fai, Deliyannis Georgia, Zeng Weiguang, Mansell Ashley, Jackson David C, Brown Lorena E
Cooperative Research Centre for Vaccine Technology, Department of Microbiology and Immunology, University of Melbourne, Victoria 3010, Australia.
Int Immunol. 2006 Dec;18(12):1801-13. doi: 10.1093/intimm/dxl114. Epub 2006 Oct 31.
Anti-viral CD8(+) T cell responses can be induced using synthetic lipopeptides and a range of different lipid moieties have been examined in a variety of model systems and in man for this purpose. Nevertheless, only limited data exist on comparative efficacy of different lipopeptides in a single model of protection so that the optimal composition for vaccination purposes remains unknown. In this study, we examined different lipid structures from bacterial or non-bacterial sources coupled to peptides representing influenza viral epitopes recognized by CD8(+) and CD4(+) T cells. These were assessed in the context of intra-nasal (i.n.) immunization in the absence of added adjuvant. The strongest immunogens were those containing bacterially derived lipids that induced dendritic cell (DC) maturation via Toll-like receptor 2 (TLR2) binding. The number of DCs induced to mature in vitro was directly associated with the strength of the CD8(+) T cell-mediated viral clearing responses in primed mice. Mice immunized with the TLR2-binding lipopeptides showed greatly enhanced numbers of specific IFN-gamma-secreting CD8(+) T cells at the site of infection after i.n. exposure to virus, which resulted in enhanced protection of the pneumonic lung. Importantly, lipopeptide-pulsed DCs were able to induce the appropriate T cells, indicating that the self-adjuvanting effects could occur in the absence of free lipopeptide interacting with additional TLR2-bearing cells in vivo. This study defines a hierarchy of lipopeptide constructs that can program DC to prime memory CD8(+) T cells that on recall function to clear influenza virus from the infected lung.
使用合成脂肽可诱导抗病毒CD8(+) T细胞反应,为此已在多种模型系统和人体中研究了一系列不同的脂质部分。然而,在单一保护模型中,关于不同脂肽比较疗效的数据有限,因此用于疫苗接种的最佳组成仍不清楚。在本研究中,我们研究了来自细菌或非细菌来源的不同脂质结构与代表CD8(+)和CD4(+) T细胞识别的流感病毒表位的肽偶联。在不添加佐剂的情况下,对这些进行鼻内(i.n.)免疫评估。最强的免疫原是那些含有细菌衍生脂质的免疫原,它们通过Toll样受体2 (TLR2)结合诱导树突状细胞(DC)成熟。体外诱导成熟的DC数量与致敏小鼠中CD8(+) T细胞介导的病毒清除反应强度直接相关。用TLR2结合脂肽免疫的小鼠在鼻内接触病毒后,感染部位分泌特异性IFN-γ的CD8(+) T细胞数量大大增加,这导致对肺部的保护增强。重要的是,脂肽脉冲DC能够诱导适当的T细胞,表明在体内不存在游离脂肽与额外的含TLR2细胞相互作用的情况下,自佐剂效应也可能发生。本研究定义了一个脂肽构建体的层次结构,该结构可以编程DC以启动记忆CD8(+) T细胞,这些T细胞在回忆功能时从感染的肺部清除流感病毒。