Wap65-2是一种鱼类特有的血浆糖蛋白，与鱼类抗细菌感染的免疫反应紧密相关。我们前期的研究进一步揭示，香鱼Wap65-2与C3存在特异性的相互作用，但其作用及机制尚不清楚。因此，本项目旨在研究Wap65-2是否通过C3影响香鱼补体激活系统，参与机体抗菌免疫反应，并起保护作用。拟通过向细菌感染的香鱼体内注射Wap65-2，检测其存活率、组织载菌量、组织病理变化、炎性因子分泌等，研究Wap65-2 对香鱼抗菌免疫保护作用的影响；通过检测溶细胞作用、激活单核/巨噬细胞活性、促单核/巨噬细胞炎性因子表达分泌，解明Wap65-2影响补体激活途径的机制；通过抗体封闭C3后检测补体激活途径作用变化，研究Wap65-2通过C3作用于补体激活途径。本项目的实施有助于解明鱼类Wap65-2在免疫反应中的保护作用机制。

The teleost warm temperature acclimation related 65 kDa protein-2 (Wap65-2) is a plasma glycoprotein. Its expressions are closely related to bacterial infection. Recently, we identified that Wap65-2 interacted with complement component 3 (C3). However, the functions and mechanism of Wap65-2 in fish immune response remain unclear. In this study, we aim to investigate whether Wap65-2 participates in immune defense against bacterial pathogens by the pathway of complement activation. By observing the survival, bacterial killing, tissue pathological section and inflammation factor expression in infected fish treated with Wap65-2, we will illustrate whether Wap65-2’s effect is improving the protective immunity. By observing the functions changes, which include cells lysis, phagocytosis and bacterial killing enhancement, and inflammatory factor induction, we will investigate the activation effect of Wap65-2 on the pathway of complement activation. By using neutralizing antibody block techniques, we will verify that C3 is a key factor in Wap65-2’s effect on the pathway of complement activation. This work will elaborate the protective mechanism of Wap65-2 on fish against bacteria.