树突状细胞（DCs）是目前已知的体内功能最强的抗原递呈细胞，是唯一能够激活初始T淋巴细胞反应的细胞，在先天性免疫、适应性免疫以及维持自身免疫耐受方面具有重要的作用，因此一直是免疫学研究的重要领域。本文简要综述了DCs的类型及其在动物体内的功能、各类DCs的细胞标记。总结了鱼类DCs的分离、纯化方法和形态学观察方法；现有研究表明，鱼类DCs具有吞噬细菌、刺激T细胞增殖、诱导CD4⁺T细胞的活化、表达DCs的标记基因、被Toll样受体的配体激活、迁移能力、引起混合淋巴细胞反应等生物学功能；不同鱼类DCs的分子标记并不完全一样；鱼类的头肾、肾、鳃、皮肤、胸腺、脾、肠等均有DCs的分布。目前，对鱼类DCs的研究虽然取得了一定进展，但仍有许多重要问题需要解决：①鱼类DCs目前缺乏明确的细胞标记，加强这方面的研究有助于提高鱼类DCs的分离、体内分布与功能的研究水平；②加强和完善鱼类DCs的分离、培养技术的研究，掌握各种鱼类DCs的分离培养方法；③加强鱼类DCs在抗原递呈中的功能研究，对深入分析鱼类免疫机理，合理设计和应用疫苗，具有重要的理论指导意义。

Dendritic cells (DCs) are currently the most powerful antigen-presenting cells in vivo and the only ones that can activate the initial T lymphocyte reaction. It plays an important role in innate immunity, adaptive immunity and maintenance of autoimmune tolerance, so it has always been an important area of immunological research. This paper briefly reviews the types of DCs and its function in animals and the cellular markers of various DCs. It summarizes separation, purification method and the method of morphological observation of DCs in fish. Results show that the dendritic cells of fish have many of the hallmarks of mammalian DCs including the ability to phagocytose small particles, stimulate T cell proliferation, induce CD4⁺ T cell activation, and the expression of dendritic cell markers, activation by Toll like receptor-ligands, and the ability to migrate in vivo and stimulate a mixed lymphocyte reaction; the molecular markers of DCs in different fishes are not exactly the same; DCs in fish were found in various organs including head kidney, kidney, gill, skin, thymus, spleen and intestine. Although some progress has been made in the research of DCs in fish, there are still many important problems to be solved:① there are currently no cellular markers for DCs in fish, so strengthening the research in this field is useful to enhance the research level of DCs' isolation, distribution in vivo and function. ② It is necessary to intensify and improve the technique of isolation and culture of DCs in fish and to master the methods of isolation and culture of various DCs. ③ Enhancing the research of DCs in antigen-presentation in fish has important theoretical significance for further research of immune mechanism and rational design and application of vaccine.

国家自然科学基金（31672683）