Understanding the contribution of T cells in infectious bursal disease virus immunopathogenesis and vaccine protection

传染性法氏囊病病毒（IBDV）是世界范围内最重要的家禽免疫抑制病原之一。虽然B淋巴细胞是病毒的主要靶细胞，但T淋巴细胞不仅参与控制病毒复制，而且还可能干扰受感染禽类的恢复。不同T细胞亚群在传染性法氏囊病（IBD）中的具体作用尚不清楚，因此需要进一步阐明以开发更有效的IBD疫苗接种策略。我们这个项目的总体目标是更好地了解不同T细胞亚群在IBD阶段的作用。我们将用不同毒力的IBDV毒株感染缺乏特异性T细胞亚群的鸡，并将它们与感染的非转基因孵化配偶进行比较。我们的具体目标是确定γδ T细胞在IBDV发病机制和肠道相关免疫中的参与，特别是在感染的急性期。此外，我们希望确定αβ T细胞参与IBDV清除和保护。为了评估调节性T细胞在恢复过程中的作用，我们将主要关注疾病的急性期后。此外，我们的目标是确定T细胞表位，作为未来候选疫苗的可能靶点。我们的工作包1（WP1）是一个合作方法的一部分，揭示了鸟类免疫反应，并将紧密嵌入在研究单位“免疫鸡”，FOR5130的背景下。各个项目将受益于彼此之间的合作，并更好地了解鸡的免疫系统与重要病原体的关系。

Infectious bursal disease virus (IBDV) is one of the most important immunosuppressive pathogens of poultry worldwide. While B lymphocytes are the main target cells of the virus, T lymphocytes are not only involved in controlling virus replication but may also interfere with the recovery of infected birds. The specific role of the different T cell subsets in infectious bursal disease (IBD) remains unclear, and therefore needs to be further elucidated to develop more efficient IBD-vaccination strategies. Our overall goal of this project is to provide a better understanding of the role of different T cell subsets in the phases of IBD. We will infect chickens that lack specific T cell subsets with IBDV strains of different virulence and compare them to infected non transgenic hatch-mates. Our specific aims are to determine the involvement of γδ T cells in IBDV pathogenesis and gut-associated immunity specifically in the acute phase of infection. Furthermore, we want to identify the involvement of αβ T cells in IBDV clearance and protection. To assess the role of regulatory T cells in the recovery process, we will focus mainly on the post-acute phase of the disease. In addition, we aim to identify T cell epitopes, as possible targets for future vaccine candidates. Our Work Package 1 (WP1) is part of a collaborative approach unravelling the avian immune response, and will be tightly embedded in the context of the research unit “ImmunoChick”, FOR5130. The individual projects will benefit from the collaborations among each other and provide a better insight into the immune system of chickens in relation to important pathogens.