Transfer of a non-human primate (NHP) in vitro functional assay for the early evaluation of TB vaccine candidates and the associated immune response

转移非人灵长类动物 (NHP) 体外功能测定，用于早期评估候选结核疫苗和相关免疫反应

• 批准号: NC/R000905/1
• 负责人: Rachel Tanner
• 金额: $ 9.63万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NC%2FR000905%2F1
• 关键词: Transfer; non; human; primate; NHP

Tuberculosis (TB) remains a serious global health threat and the only currently available vaccine, BCG, is inadequate. A more effective vaccine is urgently needed. However, as it is unclear which measures of immunity indicate protection, new vaccine candidates are currently tested in animal models such as mice, cattle and non-human primates (NHPs). NHPs are considered particularly relevant as they develop the most human-like form of TB, and the use of NHPs in the field is increasing. Animals are vaccinated and then infected with the causative agent of TB, Mycobacterium tuberculosis (M.tb), to test whether the vaccine is protective. This procedure is classified as Moderate in severity, meaning that the animals are likely to experience "short term moderate pain, suffering or distress or long-lasting mild pain, suffering or distress... or moderate impairment of the well-being or general condition". As disease progresses, animals may experience loss of body weight, fever and respiratory distress and if left untreated will eventually die of pulmonary insufficiency; necessitating humane euthanasia. For the past 6 years, Dr Tanner has led the development of an in vitro, or "test tube", assay which measures control of M.tb (or other bacteria from the same family as a surrogate) by blood or cells from a vaccinated animal or person, rather than infecting the animal or person themselves. This downgrades the severity of vaccine testing in animals considerably, falling under the 'refinement' category of the 3Rs. It also allows the testing of multiple conditions or immune responses in a set of cells from a single group of animals, and allows early down-selection of vaccine candidates going forward to testing, thereby reducing the numbers of animals required. In the longer-term, this work aims to demonstrate that the assay is a meaningful measure of protection, allowing bridging to the use of human samples (as comparison with efficacy in humans to prove this is not logistically or ethically possible). Ability to use human cells could largely replace the use of animals in TB vaccine efficacy testing.The primary aim of this project is to successfully transfer the NHP MGIT assay to two major laboratories in the field of NHP TB vaccine testing: Public Health England (PHE) and the Biomedical Primate Research Centre (BPRC) in the Netherlands. These laboratories use ~100-150 macaques in M.tb challenge experiments each year with capacity increasing, and implementation of the MGIT assay could drastically reduce the requirement for this procedure. The transfer will involve four phases: standardisation (ensuring that all laboratories are performing the assay in the same way), harmonisation (ensuring that results from the same samples are concordant between replicates within a laboratory and between laboratories), validation (ensuring that results are biologically meaningful compared to measures of protection following in vivo infection), and finally an exploratory phase to investigate the underlying mechanisms of immunity. Stored samples from studies previously conducted at PHE and BPRC have been allocated for this project, meaning that no further animal experiments will be necessary. By successfully transferring the assay, these groups will be able to implement it into their future vaccine studies, having considerable local impact. Furthermore, the project will yield data demonstrating proof-of-concept that the MGIT assay is reproducible and transferable, thus increasing interest from additional TB research groups worldwide. Evidence that this assay correlates strongly with protection from in vivo M.tb infection will further confirm biological validity and give confidence to scientists and vaccine developers.

结核病（TB）仍然是一个严重的全球健康威胁，目前唯一可用的疫苗BCG是不够的。迫切需要更有效的疫苗。然而，由于尚不清楚哪些免疫措施表明保护，目前正在动物模型中测试新的候选疫苗，如小鼠，牛和非人灵长类动物（NHP）。NHP被认为是特别相关的，因为它们发展出最类似人类的结核病形式，并且NHP在该领域的使用正在增加。动物接种疫苗，然后感染结核病的病原体，结核分枝杆菌（M.tb），以测试疫苗是否具有保护性。该程序被归类为中度严重程度，这意味着动物可能会经历“短期中度疼痛，痛苦或痛苦或长期轻度疼痛，痛苦或痛苦......”或一般健康状况的中度损害”。随着疾病的进展，动物可能会出现体重减轻、发热和呼吸窘迫，如果不治疗，最终会死于肺功能不全;需要人道安乐死。在过去的6年里，坦纳博士领导了一种体外或“试管”检测方法的开发，该方法通过接种疫苗的动物或人的血液或细胞来测量对结核分枝杆菌（或来自同一家族的其他细菌作为替代品）的控制，而不是感染动物或人本身。这大大降低了动物疫苗试验的严重性，属于3R的“细化”类别。它还允许在来自一组动物的一组细胞中测试多种条件或免疫应答，并允许在测试之前对候选疫苗进行早期向下选择，从而减少所需的动物数量。从长远来看，这项工作旨在证明该试验是一种有意义的保护措施，允许桥接人体样本的使用（与人体有效性进行比较，以证明这在逻辑上或伦理上是不可能的）。使用人类细胞的能力可以在很大程度上取代结核疫苗有效性测试中使用的动物。该项目的主要目的是将NHP MGIT检测成功转移到NHP结核疫苗测试领域的两个主要实验室：英国公共卫生（PHE）和荷兰生物医学灵长类动物研究中心（BPRC）。这些实验室每年在结核分枝杆菌挑战实验中使用约100-150只猕猴，随着容量的增加，MGIT测定的实施可以大大降低对该程序的要求。移交工作将分四个阶段进行：标准化（确保所有实验室以相同的方式进行测定），协调（确保同一样品的结果在实验室内和实验室之间的重复测定结果一致），验证（确保结果与体内感染后的保护措施相比具有生物学意义），最后是研究免疫的潜在机制的探索阶段。先前在PHE和BPRC进行的研究的储存样本已分配给该项目，这意味着无需进一步的动物实验。通过成功转移该检测方法，这些研究小组将能够将其应用于未来的疫苗研究，并在当地产生相当大的影响。此外，该项目还将产生数据，证明MGIT检测方法具有可重复性和可转移性，从而增加全球其他结核病研究小组的兴趣。该检测与体内结核分枝杆菌感染保护密切相关的证据将进一步证实生物学有效性，并为科学家和疫苗开发人员提供信心。