Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
Fish Shellfish Immunol. 2013 Oct;35(4):1293-300. doi: 10.1016/j.fsi.2013.07.043. Epub 2013 Aug 9.
Vibrio harveyi is a bacterial pathogen that affects marine vertebrates and invertebrates. In this study, we identified 13 outer membrane proteins (OMPs) from a pathogenic V. harveyi strain and analyzed their immunological properties. In vivo immunogenicity analysis showed that antibodies specific to recombinant proteins of the 13 OMPs were detected in the antiserum of V. harveyi-infected rat. When used as subunit vaccines to immunize Japanese flounder (Paralichthys olivaceus), all OMPs were able to elicit specific serum antibody production in the vaccinated fish; however, only two OMPs (OMP173 and OMP214) induced high levels (>70%) of relative percent survival. Pre-incubation of V. harveyi with the antisera of protective OMPs significantly impaired bacterial infectivity against peripheral blood leukocytes (PBL), whereas the antisera of non-protective OMPs had no apparent effect on infection. OMP173 antibodies could bind whole V. harveyi cells and exhibit bactericidal effect in a complement-dependent manner. Passive immunization showed that fish received OMP173 antiserum before being infected with V. harveyi exhibited significantly reduced mortality rate and lower bacterial loads in liver, spleen, and kidney. Finally, treatment of FG cells with OMP173 prior to V. harveyi infection protected the cells from bacterial invasion to a significant extent. Take together, these results indicate that two of the examined OMPs induce protective immunity through production of specific antibodies that block bacterial invasion, and that one OMP is likely to be involved in host cell interaction during the infection process. Thus, the immunoprotectivity of the OMPs is probably associated with functional participations of the OMPs in bacterial infection.
哈维弧菌是一种影响海洋脊椎动物和无脊椎动物的细菌性病原体。在本研究中，我们从致病性哈维弧菌菌株中鉴定了 13 种外膜蛋白（OMPs），并分析了它们的免疫学特性。体内免疫原性分析显示，感染哈维弧菌的大鼠血清中检测到针对 13 种 OMP 重组蛋白的特异性抗体。当用作亚单位疫苗免疫日本牙鲆（Paralichthys olivaceus）时，所有 OMP 都能在接种鱼中引起特异性血清抗体产生；然而，只有两种 OMP（OMP173 和 OMP214）诱导了高水平（>70%）的相对存活率。用保护性 OMP 的抗血清预先孵育哈维弧菌显著削弱了细菌对外周血白细胞（PBL）的感染力，而非保护性 OMP 的抗血清对感染没有明显影响。OMP173 抗体可以结合整个哈维弧菌细胞，并以补体依赖的方式表现出杀菌作用。被动免疫显示，在感染哈维弧菌之前接受 OMP173 抗血清的鱼死亡率显著降低，肝脏、脾脏和肾脏中的细菌载量降低。最后，在感染哈维弧菌之前用 OMP173 处理 FG 细胞可显著保护细胞免受细菌入侵。综上所述，这些结果表明，两种被检测的 OMP 通过产生特异性抗体来诱导保护性免疫，该抗体阻断细菌入侵，并且一种 OMP 可能参与感染过程中的宿主细胞相互作用。因此，OMP 的免疫保护作用可能与 OMP 在细菌感染中的功能参与有关。
