Veterinary Immunology Project, Animal Biotechnology Division, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, Havana 10600, Cuba.
Veterinary Immunology Project, Animal Biotechnology Division, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, Havana 10600, Cuba.
Fish Shellfish Immunol. 2017 Dec;71:275-285. doi: 10.1016/j.fsi.2017.10.014. Epub 2017 Oct 7.
Interferon gamma (IFN-γ) has important roles in both innate and adaptive immune responses. This cytokine plays a very important role in defining Th1 immune response in all vertebrates. In the present study, we identified and isolated for the first time the gene coding for Nile tilapia (Oreochromis niloticus) IFNγ from spleen lymphocytes. The isolated tilapia IFNγ has between 24 and 62% of amino acid identity as compared to reported sequences for other teleost fishes. It has close phylogenetic relationships with IFNγ molecules belonging to the group of Perciforms and presents the typical structural characteristics of gamma interferon molecules. The tissue expression analysis showed that IFNγ is expressed constitutively in head kidney, skin, intestine, muscle and brain. Its expression was not detected in gills by conventional RT-PCR. However, under conditions of stimulation with Poly I:C and LPS, IFNγ expression was up-regulated in gills after 24 h post-stimulation. IFNγ expression was also induced in gills 24 h after Edwardsiella tarda infection suggesting its important role in immunity against intracellular bacteria. The recombinant protein produced in Escherichia coli induced Mx gene transcription in head kidney primary culture cells. These results are the first steps to characterize the role of tilapia IFNγ in the defense against pathogens in tilapia. Furthermore, the isolation of this molecule provides a new tool to characterize the cellular immune response to various stimuli in this organism.
干扰素 γ（IFN-γ）在先天和适应性免疫反应中都具有重要作用。这种细胞因子在所有脊椎动物中对 Th1 免疫反应的定义起着非常重要的作用。在本研究中，我们首次从罗非鱼（Oreochromis niloticus）脾脏淋巴细胞中鉴定并分离出编码尼罗罗非鱼 IFNγ 的基因。分离出的罗非鱼 IFNγ与报道的其他硬骨鱼类的序列相比，具有 24%至 62%的氨基酸同一性。它与属于鲈形目鱼类的 IFNγ 分子具有密切的系统发育关系，并具有典型的γ干扰素分子的结构特征。组织表达分析表明，IFNγ在头肾、皮肤、肠道、肌肉和脑中持续表达。传统 RT-PCR 未在鳃中检测到其表达。然而，在用 Poly I:C 和 LPS 刺激后，IFNγ 的表达在刺激后 24 小时在鳃中上调。在爱德华氏菌感染 24 小时后，在鳃中也诱导了 IFNγ 的表达，表明其在抵抗胞内细菌方面的重要作用。在大肠杆菌中产生的重组蛋白诱导头肾原代培养细胞中的 Mx 基因转录。这些结果是表征罗非鱼 IFNγ在罗非鱼防御病原体中的作用的第一步。此外，该分子的分离为研究该生物体对各种刺激的细胞免疫反应提供了新的工具。
