Replacement in vivo preclinical models to substantially refine and reduce severe protocols used in snakebite envenoming research

替换体内临床前模型，以大幅改进和减少蛇咬毒研究中使用的严格方案

• 批准号: NC/X001172/2
• 负责人: Stuart Ainsworth
• 金额: $ 34.68万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NC%2FX001172%2F2
• 关键词: Replacement; vivo; preclinical; models; substantially

Snakebite envenoming is a Neglected Tropical Disease that annually kills 85,000-130,000 and maims >400,000 people living in the world's most disadvantaged communities. Globally, all snakebite envenoming therapies, both existing and in development, are assessed for efficacy using a 40-year-old, WHO-endorsed model of "neutralisation of venom leathality".Whilst simple, this assay does not accurately reflect human envenoming and requires large numbers of mice (n=25/experiment/venom) to be subjected to highly distressing severe procedures. The objective of this proposal is to develop and validate a new in vivo model of envenoming which will have a maximum severity limit of 'moderate', require fewer mice/experiment and ultimately provide more pathologically relevant data on the efficacy of current and future envenoming therapies.This will be achieved through modifying the route of envenoming to mimic that of human envenoming. This will be achieved through local venom delivery routes frequently reflective of envenoming in humans, for example. Intradermally (i.d.), subcutaneously (s.c.) or intramuscularly (i.m.), in typical sites of human envenoming, for example on the limbs. Mice will be observed for development of signs of systemic envenoming over 12 hours. One of the key aspects of this model is that once established it will have a maximum "moderate' severity limit. During development, blood will be drawn routinely to monitor indicators of envenoming, aPTT, PT, thrombin-antithrombin levels, and specific acute phase and inflammatory markers. These biomarkers will be assessed in comparison to non-invasive murine vital signs (e.g., heart rate, respiration rate, etc) to establish suitable, reliable 'moderate' humane endpoints. Once the envenoming model has been established and validated, we will further develop a 'gold standard' comparator model of envenoming therapies, similar to models widely used in the preclinical testing of other therapeutics. Therapies to be examined will be compared to 0.5, 1. Or 2.5 x the dose of a "gold standard' therapy (i.e., one with known clinical or preclinical efficacy, either antivenom or alternative) which provides the minimum anticipated biological effect level (MABEL). This assay will reduce the numbers of mice required/assay by 40%, whilst providing directly comparative scalable dose data. Once established, we will train end users in collaborating snakebite envenoming laboratories in Kenya and India in the new model. These laboratories will then independently replicate our experiments to ensure reproducibility and reliability of the model.

蛇咬伤是一种被忽视的热带疾病，每年杀死85,000-130,000人，而有40万人> 40万人生活在世界上最弱势的社区中。在全球范围内，所有蛇咬合蛋白疗法均被现有的和开发中的疗法，使用40岁的人使用的“中和毒液中和毒液中和毒液中和模型”的功效。该提案的目的是开发和验证一种新的体内模型模型，该模型将具有“中度”的最大严重性极限，需要更少的小鼠/实验，并最终提供了有关当前和未来的Envishoming Therapies疗效的更具病理相关的数据。这将通过修改对人类的影响来实现这一目标。例如，这将通过当地的毒液递送路线来实现，例如，人们经常反映人类的毒素。在典型的人类蛋白蛋白的典型部位，例如在四肢上，在典型的部位（i.m.），皮下（s.c.）或肌肉内（i.m.），皮下（i.m.）（i.m.将观察到小鼠在12个小时以上的全身性融合迹象的发展。该模型的关键方面之一是，一旦建立，它将具有最大的“中等”的磨e度限制。在发育过程中，通常会抽血，以监视感染，APTT，PT，PT，凝血酶 - 抗凝血酶水平以及特定的急性相位和炎症标记物的指标。这些生物标记将与非官员相比，将其与次数相比。建立合适的“中等”人道的终点。功效，抗蛇毒或替代性），该功效提供了最低预期的生物学效应水平（MABEL）。该测定法会将所需的小鼠的数量减少40％，同时直接提供比较可伸缩剂量数据。建立后，我们将培训最终用户，以合作在肯尼亚和印度的新模式下合作蛇咬的实验室。然后，这些实验室将独立复制我们的实验，以确保模型的可重复性和可靠性。