波里氏囊在刺参应答病原菌侵染中的作用及机制研究

免疫功能研究一直是关于棘皮动物的研究热点。近年来，越来越多的研究提示，海参波里氏囊不仅具有调节水管系统内压力的功能，其在宿主免疫系统中也发挥着重要作用。然而，当病原微生物侵染时，海参波里氏囊如何进行应答反应，其是否参与海参的抗感染免疫尚不清楚。本项目以我国主要海参养殖品种—“刺参”为对象，将“化皮病”病原—灿烂弧菌进行体腔注射感染后，研究刺参波里氏囊的形态结构动态变化；进行囊壁中病原侵染示踪及组织应答分析，研究囊壁中体腔细胞增殖动态；分析囊腔内体腔细胞对病原侵染的应答反应，并进一步利用单细胞转录组学技术解析作用机制。通过以上研究，以期阐明波里氏囊在刺参应答病原菌侵染中的作用。研究结果可使我们进一步了解海参波里氏囊的生物学功能，对解析海参的免疫系统及防御机制提供更多资料，对从比较免疫学角度探讨动物免疫系统进化提供更多参考；同时对保障刺参的健康养殖及产业可持续发展具有重要的实际应用价值。

The study of immune function has been a hotspot of echinoderms. More and more evidence shows that sea cucumber's polian vesicle not only has the function of regulating the pressure in the water-vascular system, but also plays an important role in the host immune system. However, it is not clear how the sea cucumber's polian vesicle responds when infected by pathogenic microorganisms, and whether it is involved in the sea cucumber's anti-infection immunity. In this project, the main breeding species of sea cucumber in China -Apostichopus japonicus, will be usesd as the object to study the dynamic changes of the morphology and structure of sea cucumber's polian vesicle after the pathogen of “skin ulceration syndrome”-Vibrio splendidus infection. The trace of pathogen infection and the analysis of tissue response in the cyst wall of polian vesicle will be studied by monoclonal antibody labeling. The proliferation of coelomocytes in the cyst wall of polian vesicle after V. splendidus will be analyzed by using EdU labeling. The response of coelomocytes in the lumen of the polian vesicle to pathogen infection will be studied and the mechanism will be further analyzed by single cell transcriptome. Through the above studies, we hope to elucidate the function and mechanism of sea cucumber's polian vesicle in response to pathogen infection. The results can help us to further understand the biological function of sea cucumber's polian vesicle, provide more information for the immune system and defense mechanism of sea cucumber, and provide more references for the discussion of animal immune system evolution from the perspective of comparative immunology. At the same time, it has important practical application value to ensure the healthy breeding of A. japonicus and the sustainable development of the industry.