Identification and innate immunity mechanism of protective immunogens from extracellular proteins of Edwardsiella tarda
Identification and innate immunity mechanism of protective immunogens from extracellular proteins of Edwardsiella tarda
复制标题
迟缓爱德华氏菌胞外蛋白保护性免疫原的鉴定及天然免疫机制
DOI：
10.1016/j.fsi.2019.12.020
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发表时间：
2020-02-01
影响因子：
4.7
通讯作者：
Li, Hui
中科院分区：
文献类型：
--
作者：
Li, Lu;Song, Ming;Li, Hui
水产养殖业中最重要的新兴病原体之一是迟缓爱德华氏菌，它给全球养殖鱼类造成了巨大损失。针对迟缓爱德华氏菌的保护性免疫原的鉴定愈发受到重视。我们之前对38种迟缓爱德华氏菌胞外分泌蛋白中的20种重组蛋白进行了研究，并在斑马鱼模型中鉴定出10种为保护性免疫原。在此，我们克隆了剩余18个基因中的10个，所得重组蛋白用于免疫保护评估。ETAE_2147（FliK）、ETAE_0654（PpdD）和ETAE_3259（DamX）被鉴定为保护性免疫原。此外，通过检测编码白细胞介素 - 1β（IL - 1β）、白细胞介素 - 6（IL - 6）、白细胞介素 - 8（IL - 8）、补体3b（C3b）和核因子 - κB（NF - κB）的先天免疫基因，探究了它们的保护机制。在感染的前48小时内，这三种保护性免疫原刺激斑马鱼产生的这五种免疫基因的表达，比非保护性免疫原更高且更持久。此外，这些保护性免疫原易于受到宿主产物的调控，这有助于宿主与病原体之间的相互交流，因此它们成为了疫苗候选物。这些结果为理解保护性免疫原的作用机制指明了方向。
One of the most important emerging pathogens in the aquaculture industry is Edwardsiella tarda, and it causes extensive losses in farmed fish globally. The identification of protective immunogens against E. tarda is increasingly valued. We previously investigated 20 recombinant proteins of 38 E. tarda extracellular secretory proteins and identified 10 as protective immunogens in a zebrafish model. Here, we clone 10 of the remaining 18 genes, and the resulting recombinant proteins are used for evaluation of immune protection. ETAE_2147 (FliK), ETAE_0654 (PpdD), and ETAE_3259 (DamX) are identified as protective immunogens. Furthermore, their protection mechanism is explored by the detection of innate immunity genes encoding IL-1b, IL-6, IL-8, C3b, and NF-kappa B. The three protective immunogens stimulate zebrafish to produce higher and more lasting expression of the five immunity genes than non-protective immunogens during the first 48 h of infection. In addition, these protective immunogens are prone to be regulated by host products, which is helpful for cross-talk between host and pathogen, and thus they become vaccine candidates. These results highlight the way to understand the working mechanisms of protective immunogens.