Developing a whipworm vaccine composed of virus-like particles expressing Trichuris T cell epitopes.

疫苗接种是全球卫生领域最大的进步之一；然而，大多数成功的疫苗都是凭经验制造的。在基础生物科学的背景下，我们仍然对多少疫苗有效以及它们触发保护性免疫反应的机制知之甚少。抗原递送到正确的抗原提呈细胞对于T细胞反应的质量至关重要。然而，针对特定抗原提呈细胞群体的靶向在疫苗设计中往往被忽视。鞭虫(鞭虫)是一种土壤传播的蠕虫寄生虫，影响全球约5亿人。感染很常见，特别是在卫生条件差的地区，并导致发病率和儿童发育不良。在人类中预防毛滴虫的理想疫苗应该包括能引起T辅助2细胞免疫反应的蛋白质表位。这个多学科项目将使用一种新颖的、基于模块的技术，在改进的类病毒粒子(VLP)平台上，将特定抗原与针对DC上特定受体的单抗相结合。这些改良的VLP将提供一个实验系统，使疫苗能够针对正确的抗原提呈细胞群，以刺激针对这种肠道线虫寄生虫的有效T细胞反应。利用人鞭毛虫病的小鼠模型，我们将用修饰的VLP上表达的T细胞表位或由多个T细胞表位产生的合成蛋白免疫小鼠，并感染毛滴虫，以测试它们在体内启动保护性免疫反应的能力。在VLP中添加荧光标记将能够在体内进行跟踪，与多色流式细胞术相结合，将能够识别目标抗原呈递细胞的类型。目的：2.1评价携带CD4+T细胞表位的VLP在体内的细胞靶向性。荧光标记的VLP将被注射到皮下并在体内进行跟踪。这将允许评估不同的抗原提呈细胞(树突状细胞、巨噬细胞、B细胞)在引流淋巴结中对抗原的内化情况。2.评价携带CD4+T细胞表位的VLP在体内对毛滴虫的保护性免疫应答能力。携带来自旋毛虫抗原的CD4+T细胞表位或合成蛋白的VLP将在体内输送，并与旋毛虫一起挑战宿主。对感染的保护将通过减少蠕虫和细胞免疫反应的质量来监测。高剂量AKR感染和低剂量C57BL6感染将被用来模拟人类鞭毛虫病。3.通过使用VLP-蛋白A融合平台改进新型抗原递送系统来提高疫苗效力，该融合平台允许将抗原靶向树突状细胞。我们将把树突状细胞(DC)靶向抗体引入VLP平台，并在体外和体内测试DC特异性递送。我们共同提出了一项创新的建议，将使用修饰的VLP呈现多种抗原，与诱导有效的免疫反应和体内感染的保护能力相结合，从而与BBSRC关于世界级支撑生物科学的愿景很好地结合在一起。

Vaccination is one of the greatest advances in global health; however most successful vaccines have been made empirically. In the context of basic bioscience, we still have little insight into how many vaccines work and the mechanisms by which they trigger protective immune responses. Antigen delivery to the right antigen presenting cell is critically important for the quality of the T cell response. However targeting of specific antigen presenting cell populations is often ignored in vaccine design. Trichuris trichiura (whipworm) is a soil transmitted helminth parasite that affects around 500 million people worldwide. Infection is common especially in areas of poor hygiene and sanitation and results in morbidity and poor child development. The ideal vaccine to protect against T. trichiura in humans would include protein epitopes that elicit a T helper 2 cell immune response. This multidisciplinary project will use a novel, module-based technology which combines specific antigens with monoclonal antibodies targeting specific receptors on DCs, on a modified Virus Like Particle (VLP) platform. These modified VLPs will provide an experimental system enabling vaccines to be targeted to the right antigen presenting cell population in order to stimulate effective T cell responses against this gut-dwelling nematode parasite. Using the mouse model of human trichuriasis, we will immunize mice with T cell epitopes expressed on the modified VLPs, or synthetic proteins generated from multiple T cell epitopes, and infect with T. muris, to test their ability to prime for a protective immune response in vivo. Adding a fluorescent tag to the VLPs will enable tracking in vivo which, in combination with multi-colour flow cytometry, will allow the identification of the type of antigen presenting cell targeted. OBJECTIVES:2. 1. To evaluate the cellular targeting of VLPs carrying CD4+ T cell epitopes in vivo. Fluorescently labelled VLPs will be injected subcutaneously and tracked in vivo. This will allow an assessment of the internalisation of antigen by different antigen presenting cells (dendritic cells, macrophages, B cells) in the draining lymph nodes. 2. To assess the ability of VLPs carrying CD4+ T cell epitopes to prime for protective immune responses against Trichuris muris in vivo. VLPs bearing CD4+ T cell epitopes or synthetic proteins derived from Trichuris antigens, will be delivered in vivo and the host challenged with Trichuris. Protection from infection will be monitored by a reduction in worms and the quality of the cellular immune response. High dose AKR infections and low dose C57BL6 infections will be used to model human trichuriasis. 3. To improve vaccine efficacy by modifying the novel antigen delivery system using a VLP - protein A fusion platform which allows targeting of antigen to dendritic cells. We will incorporate dendritic cell (DC)-targeting antibodies into the VLP platform and test DC-specific delivery both in vitro and in vivo. Collectively we present an innovative proposal that combines the use of modified VLPs to present multiple antigens, with the ability to induce potent immune responses and protection from infection in vivo, and one that thus aligns well with the BBSRC vision of world class underpinning bioscience.