Mapping fish CD4 T cell subsets for vaccine improvement

绘制鱼类 CD4 T 细胞亚群图谱以改进疫苗

• 批准号: BB/N024052/1
• 负责人: Chris Secombes
• 金额: $ 31.34万
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FN024052%2F1
• 关键词: Mapping; fish; CD4; cell; subsets

This project involves collaboration between two teams of experts at the University of Aberdeen and University of Santiagoof Chile, conducting state-of-the-art research in complementary areas of fish immunology/fish vaccination.Aquaculture is one of the fastest growing sectors that provide food to the expanding world population. It is estimated that~50% of fish consumed worldwide are farmed, and this is projected to rise. Sustainability of fish farming relies ongood management of fish health and control of diseases. Vaccination is an effective strategy to control many commondiseases and many highly efficacious fish vaccines exist. However, the development of fish vaccines has been largelyempirical, based on whether a formulation is effective at increasing survival post-disease challenge. This is unsatisfactoryfrom both ethical and scientific perspectives. There is a clear need to establish methods to improve fish vaccinedevelopment.This project will undertake studies to characterise an important immune pathway that may be of importance for futurefish vaccine development. Vaccination relies on the stimulation of adaptive immunity in vertebrates, with long-term memoryresponses giving protection when encounter with a pathogen occurs. In mammals a key effector population driving suchresponses are T helper (Th) cells, that release intercellular mediators (cytokines), that initiate antimicrobial responses,including antibody production. These responses have to be tailored to the pathogen type, with viruses, parasites andextracellular bacteria requiring different immune mechanisms to give protection. Different Th subpopulations differentiate inresponse to these different pathogen types and host factors, and release different repertoires of cytokines to produce themost appropriate response. We know virtually nothing about these responses in fish, although many of the genes involvedin mammals are now characterised or have putative homologues likely to have equivalent function. For example Th cellsexpress CD4 on their surface, and two types of this molecule exist in teleost fish, that will likely define these cells. Here wepropose to develop antibodies to the two CD4 molecules to detect, isolate and characterise the CD4 subsets (CD4-1+, CD4-2+, CD4-1+/CD4-2+). In immunised fish, we will study their ability to express different cytokine repertoires uponrestimulation in vitro with specific antigen. Sorted CD4 cell populations will be analysed. As antigen, both a bacterial andviral protein will be used in rainbow trout, an important farmed fish in both Chile and the UK. We have developed manyreagents (eg primers for immune gene expression analysis) and immune proteins (eg recombinant cytokines) for use introut, and expect the responses to be representative of those in salmonids more generally. Following the initialexperiments, we will study the effect of adding different cytokines together with the specific antigen on the ensuingresponses, by analysing cytokine gene expression and CD4 subset variations. We will next select the cytokines showingthe most marked effects on directing these responses to link back to confirming the involvement of CD4 (putative Th) cells.This will be done by analysing cytokine gene expression in the sorted (CD4) cell subsets following antigen restimulation invitro in the presence of recombinant cytokines. These results will go a long way towards confirming the function of Thcells in fish, and will establish if they express different cytokine repertoires in response to specific antigen andcytokines. We anticipate these responses will be of value as markers of protection in future vaccine developmentprogrammes, helping to improve the efficacy of poorly performing vaccines, and to generate vaccines to emergingdiseases. They may also provide an alternative means to evaluate vaccine performance, reducing the nos of fish undergoing pathogen challenge.

该项目涉及阿伯丁大学和智利圣地亚哥大学的两个专家团队之间的合作，在鱼类免疫学/鱼类疫苗接种的互补领域进行最先进的研究。水产养殖是为不断增长的世界人口提供食物的增长最快的部门之一。据估计，全世界消费的鱼类中约有50%是养殖的，预计这一比例还会上升。渔业养殖的可持续性依赖于对鱼类健康的良好管理和疾病的控制。疫苗接种是控制许多常见疾病的有效策略，并且存在许多高效的鱼类疫苗。然而，鱼类疫苗的开发在很大程度上是经验性的，基于一种制剂是否能有效地提高疾病后的存活率。从伦理和科学的角度来看，这都是不合理的。显然需要建立改进鱼类疫苗开发的方法。本项目将进行研究，以确定一种可能对未来鱼类疫苗开发具有重要意义的重要免疫途径。疫苗接种依赖于刺激脊椎动物的适应性免疫，当遇到病原体时，长期记忆反应提供保护。在哺乳动物中，驱动这种反应的关键效应群体是T辅助（Th）细胞，其释放细胞间介质（细胞因子），启动抗微生物反应，包括抗体产生。这些反应必须根据病原体类型进行调整，病毒、寄生虫和外细胞细菌需要不同的免疫机制来提供保护。不同的Th亚群对这些不同的病原体类型和宿主因素的反应不同，并释放不同的细胞因子以产生最适当的反应。我们对鱼类的这些反应几乎一无所知，尽管许多与哺乳动物有关的基因现在已经被鉴定出来，或者有可能具有同等功能的推定同源物。例如，Th细胞在其表面表达CD 4，硬骨鱼中存在两种类型的这种分子，这可能会定义这些细胞。本文拟研制抗这两种分子的抗体，用于检测、分离和鉴定CD 4亚群（CD 4 -1+、CD 4 -2+、CD 4 -1+/CD 4 -2+）。在免疫鱼中，我们将研究它们在体外用特异性抗原再刺激后表达不同细胞因子的能力。将分析分选的CD 4细胞群。作为抗原，细菌和病毒蛋白将用于虹鳟鱼，一种重要的养殖鱼类在智利和英国。我们已经开发了许多试剂（如用于免疫基因表达分析的引物）和免疫蛋白（如重组细胞因子）用于导入，并期望这些反应能更普遍地代表鲑科动物的反应。在初步实验之后，我们将通过分析细胞因子基因表达和CD 4亚群的变化来研究加入不同细胞因子和特异性抗原对随后应答的影响。我们接下来将选择在指导这些反应上显示出最显著效果的细胞因子，以确认CD 4（推定的Th）细胞的参与，这将通过分析重组细胞因子存在下体外抗原再刺激后分选的（CD 4）细胞亚群中细胞因子基因表达来完成。这些结果将大大有助于确认鱼类Th细胞的功能，并将确定它们是否在响应特定抗原和细胞因子时表达不同的细胞因子库。我们预计这些反应将在未来的疫苗开发计划中作为保护标志物，有助于提高表现不佳的疫苗的效力，并为新出现的疾病生产疫苗。它们还可以提供一种替代方法来评估疫苗的性能，减少鱼接受病原体攻击的nos。

项目成果

Revisiting the Teleost Thymus: Current Knowledge and Future Perspectives.

• DOI: 10.3390/biology10010008
• 发表时间: 2020-12-25
• 期刊: Biology
• 影响因子: 4.2
• 作者: Barraza F;Montero R;Wong-Benito V;Valenzuela H;Godoy-Guzmán C;Guzmán F;Köllner B;Wang T;Secombes CJ;Maisey K;Imarai M
• 通讯作者: Imarai M

Interleukin (IL)-2 Is a Key Regulator of T Helper 1 and T Helper 2 Cytokine Expression in Fish: Functional Characterization of Two Divergent IL2 Paralogs in Salmonids.

白介素（IL）-2是T辅助器1和T辅助2细胞因子表达的关键调节剂：鲑鱼中两个发散IL2旁系同源物的功能表征。

• DOI: 10.3389/fimmu.2018.01683
• 发表时间: 2018
• 期刊: Frontiers in immunology
• 影响因子: 7.3
• 作者: Wang T;Hu Y;Wangkahart E;Liu F;Wang A;Zahran E;Maisey KR;Liu M;Xu Q;Imarai M;Secombes CJ
• 通讯作者: Secombes CJ