Inducing efficient cross-priming using antigen-coated yeast particles.
Inducing efficient cross-priming using antigen-coated yeast particles.
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DOI：
10.1097/cji.0b013e318181c87f
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发表时间：
2008-09
期刊：
影响因子：
--
通讯作者：
Wittrup KD
中科院分区：
文献类型：
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作者：
Howland SW;Tsuji T;Gnjatic S;Ritter G;Old LJ;Wittrup KD
酿酒酵母刺激树突状细胞（DC），并代表了一个有前途的候选人的癌症疫苗的发展。有效的交叉呈递递送至DC的抗原对于成功诱导细胞免疫是必需的。在这里，我们提出了一种基于酵母的疫苗方法，该方法不依赖于酵母表达所选抗原的能力，而是单独产生并与酵母细胞壁缀合。缀合方法是位点特异性的（基于SNAP标签），并且被设计为促进DC吞噬体中的抗原释放和随后的易位以用于交叉呈递。我们证明，相同蛋白质的非位点特异性化学缀合阻碍了交叉呈递。通过插入不变链胞外域作为接头，进一步加速了吞噬体抗原的释放，该接头被组织蛋白酶S快速切割。递送的抗原的剂量以几种方式增加：通过使用具有更高表面胺密度的酵母菌株，通过使用酵母壳（细胞壁片段）代替整个细胞，以及通过缀合多层抗原。新的多层缀合方案利用Sfp磷酸泛酰巯基乙胺基转移酶并保持位点特异性;它使抗原剂量随着层数线性增长。我们表明，用1层癌症-睾丸抗原NY-ESO-1包被的完整酵母细胞和带有3层的酵母壳能够在体外交叉致敏幼稚CD 8 + T细胞，后者在10天后产生更高频率的抗原特异性细胞。这种交叉呈递有效的抗原缀合方案不限于酵母，并且可以容易地应用于其他颗粒疫苗的开发。
Saccharomyces cerevisiae stimulates dendritic cells (DCs) and represents a promising candidate for cancer vaccine development. Effective cross-presentation of antigen delivered to DCs is necessary for successful induction of cellular immunity. Here, we present a yeast-based vaccine approach that is independent of yeast’s ability to express the chosen antigen, which is instead produced separately and conjugated to the yeast cell wall. The conjugation method is site-specific (based on the SNAP-tag) and designed to facilitate antigen release in the DC phagosome and subsequent translocation for cross-presentation. We demonstrate that nonsite-specific chemical conjugation of the same protein hinders cross-presentation. Phagosomal antigen release was further expedited through the insertion of the invariant chain ectodomain as a linker, which is rapidly cleaved by Cathepsin S. The dose of delivered antigen was increased in several ways: by using yeast strains with higher surface amine densities, by using yeast hulls (cell wall fragments) instead of whole cells, and by conjugating multiple layers of antigen. The novel multilayer conjugation scheme takes advantage of Sfp phosphopantetheinyl transferase and remains site-specific; it enables the antigen dose to grow linearly with the number of layers. We show that whole yeast cells coated with 1 layer of the cancer-testis antigen NY-ESO-1 and yeast hulls bearing 3 layers were able to cross-prime naive CD8+ T cells in vitro, with the latter resulting in higher frequencies of antigen-specific cells after 10 days. This cross-presentation-efficient antigen conjugation scheme is not limited to yeast and can readily be applied toward the development of other particulate vaccines.