Dissecting cell surface protein diversity to enhance leptospiral vaccine efficacy.

剖析细胞表面蛋白质多样性以增强钩端螺旋体疫苗的功效。

• 批准号: BB/W016133/1
• 负责人: Nicholas Evans
• 金额: $ 93.91万
• 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: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FW016133%2F1
• 关键词: Dissecting; cell; surface; protein; diversity

Leptospirosis, caused by Leptospira bacteria, is a worldwide, severe infectious disease affecting several different host species including cattle, dogs and man. Globally, cattle are greatly afflicted resulting in severe economic losses, reduced food security, substantial antimicrobial use and animal to man (zoonotic) transmission. Economic cost to the UK is £22.3 million/year with much greater costs expected for tropical regions, including many low to middle income countries (LMICs), due to substantially greater disease burden and more severe disease. Current bovine leptospirosis (BL) vaccines have a limited range of specificity and require cold chain transport and storage, which is problematic in the many tropical, frequently LMIC regions with greatest disease burden. Making vaccines more broadly protective and easily accessible will increase uptake globally, decreasing global antibiotic use and antimicrobial resistance development. This is especially important for leptospirosis which is considered to be emerging/re-emerging globally and being driven by global warming and associated increases in extreme climatic events, such as flooding. Bacterial surface proteins are considered important targets to provide cross-protective and long lasting immunity against a range of Leptospira species and serovars. Immune evasion by leptospires, is considered to involve these bacteria coating themselves with host molecules. Whilst the different leptospire bacteria involved in disease are diverse, they must have near identical machinery for this immune evasion which must be present on the bacterial surface to allow for host binding and/or damage and therefore represent ideal vaccine targets. Thus, characterisation of key bacterial surface proteins, especially those involved in immune evasion and determining their mechanism of interaction should allow for development of novel vaccines or therapeutics. Recent research, mutating bacterial surface proteins to prevent binding of host molecules, as well as enhancing protein stability, has increased the protective ability of these bacterial components when used as vaccines. The application of such novel protein engineering has been used in the development pathway for an important human pathogen vaccine which is now licensed and can now be applied to veterinary pathogens. Here, we combine synthetic biology, artificial intelligence and in silico (bioinformatic) approaches to guide engineering of key cell surface proteins to develop a novel thermostable vaccine with broad Leptospira specificity and enhanced efficacy.This study will 1) investigate vaccine candidate diversity across leptospire species including surveying whether variants from some species exhibit adhesion preference for molecules from specific host species resulting in known host specificity and identify, whether variants from commensal (harmless) relatives lack ability to attach to host molecules, 2) use sequence diversity/conservation and differences in adhesion ability together with artificial intelligence (AI) generated structural models with in silico approaches to engineer the surface proteins to restrict host interaction which in line with recent human pathogen disease work should allow for more effective vaccines, 3) use sequence diversity together with AI generated structural models and in silico approaches to synthesise surface proteins with enhanced stability, 4) use a rodent models of disease to identify those engineered bacterial surface proteins most likely to offer protection from a range of the disease causing bacteria.Investigating BL vaccine candidates by the diverse and comprehensive methods described above, should help characterise the causal bacteria, improve understanding of the disease, substantially progress the vaccine development pipeline and/or identify novel therapeutics. Such studies are both timely and much needed to enable the prevention or even eradication of this severe, important global disease.

钩端螺旋体病是由钩端螺旋体属细菌引起的一种世界性的严重传染病，影响包括牛、狗和人在内的几种不同的宿主物种。在全球范围内，牛受到极大的折磨，导致严重的经济损失、粮食安全降低、大量使用抗菌剂和动物到人（人畜共患）传播。英国的经济成本为2230万英镑/年，热带地区的成本预计会更高，包括许多低收入到中等收入国家（LMIC），因为疾病负担更大，疾病更严重。目前的牛钩端螺旋体病（BL）疫苗具有有限的特异性范围，需要冷链运输和储存，这在许多热带地区，通常是LMIC地区的疾病负担最大的问题。使疫苗具有更广泛的保护性和更容易获得将增加全球的吸收，减少全球抗生素的使用和抗菌素耐药性的发展。这对于钩端螺旋体病尤其重要，因为钩端螺旋体病被认为是全球新出现/重新出现的疾病，并受到全球变暖和极端气候事件（如洪水）相关增加的驱动。细菌表面蛋白被认为是提供针对一系列钩端螺旋体物种和血清型的交叉保护和持久免疫的重要靶标。钩端螺旋体的免疫逃避被认为涉及这些细菌用宿主分子包裹自己。虽然疾病中涉及的不同钩端螺旋体细菌是多样的，但它们必须具有几乎相同的用于这种免疫逃避的机制，该机制必须存在于细菌表面上以允许宿主结合和/或损伤，因此代表理想的疫苗靶标。因此，表征关键的细菌表面蛋白，特别是那些参与免疫逃避和确定它们的相互作用机制，应允许开发新的疫苗或治疗剂。最近的研究，突变细菌表面蛋白以防止宿主分子结合，以及增强蛋白质稳定性，增加了这些细菌成分用作疫苗时的保护能力。这种新型蛋白质工程的应用已被用于重要的人类病原体疫苗的开发途径中，该疫苗现已获得许可，现在可以应用于兽医病原体。在这里，我们结合了联合收割机合成生物学，人工智能和计算机（生物信息学）方法来指导关键细胞表面蛋白的工程化，以开发具有广泛钩端螺旋体特异性和增强功效的新型热稳定疫苗。研究钩端螺旋体物种间的候选疫苗多样性，包括调查来自某些物种的变体是否表现出对来自特定宿主物种的分子的粘附偏好，宿主特异性和识别，是否从寄生虫变异（无害的）亲属缺乏附着到宿主分子的能力，2）使用序列多样性/保守性和粘附能力的差异以及人工智能（AI）生成的结构模型，用计算机模拟方法来工程化表面蛋白以限制宿主相互作用，这与最近的人类病原体疾病工作一致，应该允许更有效的疫苗，3）使用序列多样性以及AI生成的结构模型和计算机模拟方法来合成具有增强的稳定性的表面蛋白，4）使用啮齿动物疾病模型来鉴定那些最有可能提供对一系列致病细菌的保护的工程化细菌表面蛋白。通过上述多样化和全面的方法研究BL疫苗候选物，应该有助于鉴定致病细菌，提高对疾病的理解，大大推进疫苗开发管道和/或确定新的治疗方法。这些研究是及时的，也是非常必要的，以便能够预防甚至根除这一严重的全球性疾病。

项目成果

Characterisation of Putative Outer Membrane Proteins from Leptospira borgpetersenii Serovar Hardjo-Bovis Identifies Novel Adhesins and Diversity in Adhesion across Genomospecies Orthologs

• DOI: 10.3390/microorganisms12020245
• 发表时间: 2024-02-01
• 期刊: MICROORGANISMS
• 影响因子: 4.5
• 作者: Kamaruzaman，Intan Noor Aina;Staton，Gareth James;Evans，Nicholas James
• 通讯作者: Evans，Nicholas James