海水养殖鱼类高效免疫的细胞与分子基础

The cultivation of marine fish is gradually moving towards the mode of industrial farming in China, and the applications of vaccines in prevention of fish diseases has became a mainstream direction. However, in order to achieve high efficient vaccination, it is necessary to investigate the characteristics of immune responses in immunized fish, which could elucidate the mechanisms of immune response induced by vaccination. Previously, the monoclonal antibodies against different Igs and molecular markers of T/B cells have been produced, and were applied to study the systematic and mucosal immune responses of flounder. In the present project, aiming at the bacterial and viral pathogens in flounder cultivation, the response, secretion and function of different Igs were investigated in responding to different immunogens via different immunization routes; the subsets of T/B lymphocytes were identified and their responses after immunization were also ivestigated; the characteristics of mucosal response were studid in flounder after immersion with different antigens; the activation and regulation mechanism of cytokines on immune response were explored; the antigen uptake and transport dynamics after immunization were also monitored. The resultant data of the project will reveal the correlation between the immune effects and the immune responses, and lay the cellular and molecular basis for the high efficient vaccination in marine fish, and also provide the theoretical foundation and technical support for the high efficient vaccination in prevention of fish diseases.

我国海水养殖鱼类正逐步走向工业化养殖的道路，应用疫苗开展免疫防治将是今后鱼类病害防治的主流发展方向。然而，要科学高效地实现鱼类疾病的免疫防治，就必须系统而深入地探究鱼体免疫应答规律，以阐释鱼类对疫苗接种的免疫响应与应答机制。本项目以研制的抗牙鲆不同类型免疫球蛋白及T/B淋巴细胞亚群单抗为工具，在牙鲆系统与黏膜免疫应答特征研究的工作基础上，针对牙鲆养殖过程中危害严重的细菌与病毒性病原，以不同免疫途径接种牙鲆，研究不同类型免疫球蛋白对免疫接种的响应、分泌及功能差异；开展T/B淋巴细胞亚群的鉴定及其免疫应答特征研究；研究牙鲆黏膜系统对浸泡免疫的响应与应答特征；研究细胞因子对免疫应答的激活与调控作用；研究免疫接种后鱼体对抗原摄入及转运动态。研究结果将有力揭示疫苗免疫效果与免疫应答之间的相关性，为海水养殖鱼类高效免疫奠定细胞与分子基础，为鱼类疾病高效免疫防治提供理论依据与技术支撑。

我国海水养殖鱼类正逐步走向工业化养殖的道路，应用疫苗开展免疫防治将是今后鱼类病害防治的主流发展方向。然而，要科学高效地实现鱼类疾病的免疫防治，就必须系统而深入地探究鱼体免疫应答规律，以阐释鱼类对疫苗接种的免疫响应与应答机制。项目针对我国北方重要海水养殖鱼类牙鲆为研究对象，研制出其重要病原多种不同类型的候选疫苗；制备获得牙鲆T/B 淋巴细胞、树突状细胞、中性粒细胞等重要免疫细胞的表面标志分子特异性抗体，解析了各类免疫细胞的分群、分布特征及其对不同类型候选疫苗的增殖响应动态；追踪了腹腔注射和肌肉注射免疫后牙鲆抗原摄入的动态特征；从细胞、抗体及基因表达等水平上初步探明了牙鲆对各类型疫苗的差异免疫应答特征；阐明了多种白细胞介素与趋化因子的佐剂效应；明晰了牙鲆B 淋巴细胞的吞噬作用及其调控机理，以及吞噬相关受体介导的信号传递模式；解析了牙鲆多聚免疫球蛋白受体（pIgR）的基本免疫学特性和其介导的抗原清除过程。研究成果系统深入解析了以牙鲆为代表的海水养殖鱼类免疫系统基本特征及其对免疫接种和病原侵染的应答规律，为构建高效免疫策略及新型鱼类疫苗评价技术体系奠定了理论基础。