Engineering resistance to Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)

工程抗猪繁殖与呼吸综合征病毒（PRRSV）

• 批准号: BB/L004143/1
• 负责人: Alan Archibald
• 金额: $ 69.94万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FL004143%2F1
• 关键词: Engineering; resistance; Porcine; Reproductive; Respiratory

Porcine Reproductive and Respiratory Syndrome (PRRS) is a viral disease of pigs that causes major economic losses. PRRS virus (PRRSV) is a rapidly evolving small enveloped RNA virus. Whilst improvements have been effected with changes in husbandry and vaccination, PRRS still has major impacts on pig health and welfare. PRRS accounts for ca.1/3 of the cost of infectious disease to the US pig industry, ~$600M p.a.. PRRS is the most costly disease to pig industries of Europe and North America and new PRRSV variants have the potential to be even more devastating. PRRSV infects subpopulations of differentiated macrophages, with alveolar macrophages being the major target cells.There is growing evidence from in-vitro and in-vivo challenge experiments and field studies that there is host genetic variation in responses to and outcomes of PRRSV infection. Thus, there is scope for genetically improving traits related to the capacity of pigs to cope with PRRS infection and disease at the innate immune level. However, breeding for disease resistance is constrained by the nature of the available genetic variation in susceptibility to infection. Whilst evidence for genetic variation in host responses to infection with PRRSV exists, the genetic control of these responses is polygenic and there is no evidence to date of major genes conferring complete resistance to PRRSV.The increased efficiency and sophistication of methods to genetically modify farmed animals offers alternative approaches to generate animals which are genetically resistant to specific pathogens. The approaches to engineering resistance to a viral pathogen, such as PRRSV, include interfering with the receptor(s) through which the virus gains entry, for example by ablating the receptor or over-expressing a soluble form of the receptor which could bind the virus and blocks its entry.Recent studies have revealed the molecular mechanisms through which PRRSV enters macrophages during infection. The macrophage specific scavenger receptor cysteine-rich (SRCR) CD163 has been shown to be a key role in these processes. Cells which are refractory to PRRSV infection can be converted to a PRRSV permissive state by the addition of transgenes expressing CD163. Treating susceptible porcine alveolar macrophages with anti-CD163 antibodies reduces PRRSV infection in a dose-dependent manner. There is evidence to indicate that the SRCR domain 5 of the CD163 protein is the key component involved in PRRSV entry and release.The aim of this project is to test the hypothesis that cells and pigs can be engineered to be resistant to infection with PRRSV by genetic modification of the CD163 gene. We propose three strategies to engineer resistance to PRRSV: knocking out the CD163 gene; knocking out the SRCR domain 5 of the CD163 gene and over-expressing a soluble form of the extracellular domains of CD163.

猪繁殖与呼吸综合征（PRRS）是猪的一种病毒性疾病，造成重大经济损失。PRRS病毒（PRRSV）是一种快速进化的小包膜RNA病毒。虽然随着畜牧业和疫苗接种的变化，情况有所改善，但PRRS仍然对猪的健康和福利产生重大影响。PRRS占美国养猪业传染病成本的约1/3，每年约6亿美元。PRRS是欧洲和北美养猪业最昂贵的疾病，新的PRRSV变种有可能更具破坏性。PRRSV感染分化的巨噬细胞亚群，以肺泡巨噬细胞为主要靶细胞。越来越多的体外和体内挑战实验和实地研究证据表明，宿主对PRRSV感染的反应和结果存在遗传变异。因此，在先天免疫水平上，与猪应对PRRS感染和疾病的能力相关的遗传改良性状有很大的空间。然而，抗病育种受到现有感染易感性遗传变异性质的限制。虽然有证据表明宿主对PRRSV感染的反应存在遗传变异，但这些反应的遗传控制是多基因的，迄今为止没有证据表明主要基因对PRRSV具有完全抗性。对养殖动物进行基因改造的方法的效率和复杂性的提高，为产生对特定病原体具有遗传抗性的动物提供了替代方法。设计对病毒病原体（如PRRSV）的抗性的方法包括干扰病毒进入的受体，例如通过消融受体或过度表达可结合病毒并阻止其进入的受体的可溶性形式。最近的研究揭示了PRRSV在感染过程中进入巨噬细胞的分子机制。巨噬细胞特异性清道夫受体富半胱氨酸（SRCR） CD163已被证明在这些过程中起关键作用。通过添加表达CD163的转基因，对PRRSV感染不耐受的细胞可以转化为PRRSV允许状态。用抗cd163抗体治疗易感猪肺泡巨噬细胞以剂量依赖的方式减少PRRSV感染。有证据表明，CD163蛋白的SRCR结构域5是参与PRRSV进入和释放的关键成分。该项目的目的是验证这样一种假设，即通过对CD163基因进行基因修饰，可以使细胞和猪对PRRSV感染产生抗性。我们提出了三种策略来设计对PRRSV的抗性：敲除CD163基因；敲除CD163基因的SRCR结构域5，并过度表达CD163的细胞外结构域的可溶性形式。

项目成果

Precision engineering for PRRSV resistance in pigs: Macrophages from genome edited pigs lacking CD163 SRCR5 domain are fully resistant to both PRRSV genotypes while maintaining biological function.

• DOI: 10.1371/journal.ppat.1006206
• 发表时间: 2017-02
• 期刊: PLoS pathogens
• 影响因子: 6.7
• 作者: Burkard C;Lillico SG;Reid E;Jackson B;Mileham AJ;Ait-Ali T;Whitelaw CB;Archibald AL
• 通讯作者: Archibald AL

Pigs Lacking the Scavenger Receptor Cysteine-Rich Domain 5 of CD163 Are Resistant to Porcine Reproductive and Respiratory Syndrome Virus 1 Infection.

缺乏CD163的猪富含清道夫受体的富含半胱氨酸的结构域5具有对猪生殖和呼吸综合征病毒1感染的抗性。

• DOI: 10.1128/jvi.00415-18
• 发表时间: 2018-08-15
• 期刊: Journal of virology
• 影响因子: 5.4
• 作者: Burkard C;Opriessnig T;Mileham AJ;Stadejek T;Ait-Ali T;Lillico SG;Whitelaw CBA;Archibald AL
• 通讯作者: Archibald AL

Livestock 2.0 - genome editing for fitter, healthier, and more productive farmed animals.

• DOI: 10.1186/s13059-018-1583-1
• 发表时间: 2018-11-26
• 期刊: Genome biology
• 影响因子: 12.3
• 作者: Tait-Burkard C;Doeschl-Wilson A;McGrew MJ;Archibald AL;Sang HM;Houston RD;Whitelaw CB;Watson M
• 通讯作者: Watson M

Gene edited "superpigs" resist devastating disease

基因编辑的“超级猪”抵抗毁灭性疾病

• DOI: 10.25250/thescbr.brk185
• 发表时间: 2019
• 期刊: TheScienceBreaker
• 作者: Burkard C

Erratum for Burkard et al., "Pigs Lacking the Scavenger Receptor Cysteine-Rich Domain 5 of CD163 Are Resistant to Porcine Reproductive and Respiratory Syndrome Virus 1 Infection".

Burkard 等人的勘误，“缺乏 CD163 清道夫受体富含半胱氨酸结构域 5 的猪对猪繁殖与呼吸综合征病毒 1 感染有抵抗力”。

• DOI: 10.1128/jvi.00951-20
• 发表时间: 2020
• 期刊: Journal of virology
• 影响因子: 5.4
• 作者: Burkard C