Anthrax toxin as a molecular tool for stimulation of cytotoxic T lymphocytes: disulfide-linked epitopes, multiple injections, and role of CD4(+) cells.
Anthrax toxin as a molecular tool for stimulation of cytotoxic T lymphocytes: disulfide-linked epitopes, multiple injections, and role of CD4(+) cells.
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炭疽毒素作为刺激细胞毒性 T 淋巴细胞的分子工具：二硫键连接的表位、多次注射和 CD4( ) 细胞的作用。
DOI：
10.1128/iai.66.10.4696-4699.1998
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发表时间：
1998
影响因子：
3.1
通讯作者：
Starnbach,MN
中科院分区：
文献类型：
--
作者：
Ballard,JD;Collier,RJ;Starnbach,MN
我们之前已经证明，炭疽毒素衍生蛋白、保护性抗原（PA）和致死因子（LFn）的氨基末端部分可以联合使用，将异源分子传递到哺乳动物细胞的细胞质中。在这项研究中，我们检测了在PA存在下lfn肽二硫连接异二聚体对细胞毒性T淋巴细胞（CTL）的能力。产生了一个含有羧基末端活性半胱氨酸的LFn突变体。这种形式的LFn可以与合成的含有半胱氨酸的肽氧化，形成蛋白质和肽的异源二聚体。注射异二聚体加PA的小鼠产生了肽特异性CTL反应，表明该分子的功能与先前使用的遗传融合形式相似。我们还报告了对该系统的两个方面的分析结果，这些方面对实验性疫苗的开发很重要。首先，当PA + lfn -表位融合蛋白处理CD4敲除小鼠时，不能产生CTL反应，这表明CD4+辅助反应对于用PA- lfn系统刺激特异性CTL是必不可少的。其次，我们现在表明，初次注射该系统不会产生任何可检测到的针对疫苗成分的抗体反应，并且先前的免疫接种对随后注射不相关表位时引发CTL反应没有影响。
We have previously demonstrated that anthrax toxin-derived proteins, protective antigen (PA) and the amino-terminal portion of lethal factor (LFn), can be used in combination to deliver heterologous molecules to the cytosol of mammalian cells. In this study we examined the ability of an LFn-peptide disulfide-linked heterodimer to prime cytotoxic T lymphocytes (CTL) in the presence of PA. A mutant of LFn that contains a carboxy-terminal reactive cysteine was generated. This form of LFn could be oxidized with a synthetic cysteine containing peptide to form a heterodimer of the protein and peptide. Mice injected with the heterodimer plus PA mounted a peptide-specific CTL response, indicating that this molecule functioned similarly to the genetically fused forms used previously. We also report the results of an analysis of two aspects of this system important for the development of experimental vaccines. First, CD4 knockout mice were unable to generate a CTL response when treated with PA plus an LFn-epitope fusion protein, suggesting that CD4+helper responses are essential for stimulating specific CTL with the PA-LFn system. Second, we now show that primary injection with this system does not generate any detectable antibody response to the vaccine components and that prior immunization has no effect on priming a CTL response to an unrelated epitope upon subsequent injection.