Wei He, Yin Licheng, Feng Shiyu, Wang Xinyan, Yang Kun, Zhang Anying, Zhou Hong
School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
Fish Shellfish Immunol. 2015 Jun;44(2):445-52. doi: 10.1016/j.fsi.2015.03.023. Epub 2015 Mar 21.
In fish, the knowledge on the regulation of inflammatory responses is limited. In the present study, LPS rapidly increased the mRNA levels of grass carp pro-inflammatory factors, including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), inducible nitric oxides synthase (iNOS) and IL-8 in monocytes/macrophages, indicating the occurrence of innate inflammatory responses in fish as seen in mammals. Intriguingly, the gene expression and protein secretion of grass carp IL-10 (gcIL-10) and TGF-β1 (gcTGF-β1) were induced by LPS in the same cell model, promoting us to clarify their roles in regulating inflammatory response. Results revealed that grass carp IL-10 polyclonal antibody (anti-gcIL-10 pAb) and grass carp TGF-β1 monoclonal antibody (anti-gcTGF-β1 mAb) could amplify the stimulation of LPS on the mRNA levels of tnfα, il1β, inos and il8, suggesting the inhibitory tone of endogenous IL-10 and TGF-β1 in LPS-challenged immune responses. This notion was further supported by the fact that recombinant grass carp IL-10 (rgcIL-10) and recombinant grass carp TGF-β1 (rgcTGF-β1) attenuated LPS-stimulated tnfα, il1β, inos and il8 gene expression in monocytes/macrophages. Further study revealed that rgcIL-10 and rgcTGF-β1 impaired NF-κB activation by blocking LPS-induced grass carp IκBα (gcIκBα) protein degradation in the cells. In addition, the correlation between gcIL-10 and gcTGF-β1 in this regulation was examined by immunoneutralization, unveiling that anti-gcTGF-β1 mAb and anti-gcIL-10 pAb were unable to alter the inhibitory effects of rgcIL-10 and rgcTGF-β1 on pro-inflammatory factors expression in grass carp monocytes/macrophages, respectively. This dual and parallel effect of gcIL-10 and gcTGF-β1 strengthened their importance in controlling inflammatory responses. Taken together, our findings shed a light on the functional role, regulatory mechanism and relationship of fish IL-10 and TGF-β1 in regulating inflammatory response.
在鱼类中，关于炎症反应调节的知识有限。在本研究中，脂多糖（LPS）迅速提高了草鱼促炎因子的mRNA水平，这些因子包括单核细胞/巨噬细胞中的肿瘤坏死因子α（TNF-α）、白细胞介素-1β（IL-1β）、诱导型一氧化氮合酶（iNOS）和IL-8，这表明鱼类中发生了与哺乳动物类似的先天性炎症反应。有趣的是，在同一细胞模型中，LPS诱导了草鱼IL-10（gcIL-10）和转化生长因子-β1（gcTGF-β1）的基因表达和蛋白分泌，促使我们阐明它们在调节炎症反应中的作用。结果显示，草鱼IL-10多克隆抗体（抗gcIL-10 pAb）和草鱼TGF-β1单克隆抗体（抗gcTGF-β1 mAb）能够增强LPS对tnfα、il1β、inos和il8 mRNA水平的刺激作用，这表明内源性IL-10和TGF-β1在LPS激发的免疫反应中具有抑制作用。重组草鱼IL-10（rgcIL-10）和重组草鱼TGF-β1（rgcTGF-β1）减弱了LPS刺激的单核细胞/巨噬细胞中tnfα、il1β、inos和il8基因表达，这一事实进一步支持了这一观点。进一步研究表明，rgcIL-10和rgcTGF-β1通过阻断细胞中LPS诱导的草鱼IκBα（gcIκBα）蛋白降解来损害NF-κB的激活。此外，通过免疫中和检测了gcIL-10和gcTGF-β1在该调节中的相关性，结果表明抗gcTGF-β1 mAb和抗gcIL-10 pAb分别无法改变rgcIL-10和rgcTGF-β1对草鱼单核细胞/巨噬细胞中促炎因子表达的抑制作用。gcIL-10和gcTGF-β1的这种双重且平行的作用强化了它们在控制炎症反应中的重要性。综上所述，我们的研究结果揭示了鱼类IL-10和TGF-β1在调节炎症反应中的功能作用、调节机制及相互关系。
