Multivalent display of anthrax toxin inhibitors

炭疽杆菌产生一种毒素，导致细胞死亡和受感染个体的死亡。即使细菌感染本身被抗生素控制，感染者也经常因为B体内产生的炭疽毒素（AT）而死亡。炭疽菌与人体细胞结合，被内吞并杀死细胞。因此，开发特异性抗毒素，防止AT结合人体细胞是必要的，以有效地治疗炭疽暴露。这就是这个项目资助的目标。J. Young和J. Collier的研究小组发现并表征了AT与其细胞受体之间的相互作用。这项工作推动了新型肽基炭疽抗毒素的发现和开发（项目1和2）。在这里，我们提出使用植物病毒颗粒豇豆花叶病毒（CPMV）或昆虫病毒鸡群病毒（FHV）作为展示平台，以多价形式展示抑制肽和基于可溶性AT受体的蛋白质（项目3-5）。将生产这些多价平台并测试其作为体外和体内抗毒素的功效。这些病毒对热和酸稳定，易于大量生产。这两种病毒在遗传、生物化学和结构上都得到了很好的表征，并且可以被工程化或化学修饰，以在其表面上展示多个拷贝的外源免疫原性或抗毒素肽序列。曼彻斯特小组（项目3）先前已经表明，通过在CPMV上多价展示抑制肽，可以在体外和体内有效地阻断病毒-细胞受体相互作用。利用这一令人兴奋的结果作为概念的证明，我们将测试多价 在CPMV和FHV上展示AT抑制肽将导致产生一组新的和有效的炭疽抗毒素和疫苗试剂。

Bacillus anthracis produces a toxin that causes cell death and mortality in infected individuals. Even if the bacterial infection itself is controlled by antibiotics, an infected person often dies because the anthrax toxin (AT) produced in vivo by B. anthracis binds to human cells, is endocytosed, and kills the cells. Therefore development of specific antitoxins that prevent AT from binding to human cells is necessary for effectively treating anthrax exposure,. This is the goal of this Program Project grant. The groups of J. Young and J. Collier have discovered and characterized the interaction between AT and its cellular receptors. This work fuels the discovery and development of novel peptide-based anthrax anti-toxins (Projects 1 and 2). Here we propose to display the inhibitory peptides and soluble AT receptor-based proteins in a multivalent form using the plant virus particle cowpea mosaic virus (CPMV) or the insect virus Flock house virus (FHV) as display platforms (Projects 3-5). These multivalent platforms will be produced and tested for their efficacy as antitoxins both in vitro and in vivo. These viruses are heat and acid-stable and are easy to produce in large quantities. Both viruses have been very well characterized genetically, biochemically and structurally and can either be engineered, or chemically modified, to display multiple copies of foreign immunogenic or antitoxin peptide sequences on their surface. The Manchester group (project 3) has previously shown that a virus-cellular receptor interaction can be efficiently blocked, both in vitro and in vivo, by the multivalent display of an inhibitory peptide on CPMV. Using this exciting result as a proof of concept, we will test the hypothesis that multivalent display of AT inhibitory peptides on CPMV and FHV will lead to the creation of a panel of new and effective anthrax antitoxins and vaccine reagents.