title: Dual-parallel inhibition of IL-10 and TGF-β1 controls LPS-induced inflammatory response via NF-κB signaling in grass carp monocytes/macrophages.
abstract: 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.
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: He
authors: H
authors: Wei
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: Licheng
authors: L
authors: Yin
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: Shiyu
authors: S
authors: Feng
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: Xinyan
authors: X
authors: Wang
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: Kun
authors: K
authors: Yang
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
authors: Anying
authors: A
authors: Zhang
authors: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China. Electronic address: zhouhongzh@uestc.edu.cn.
authors: Hong
authors: H
authors: Zhou
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D002347:Carps; D017931:DNA Primers / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005393:Fish Diseases / Q000139:chemically induced* / Q000517:prevention & control*; D007249:Inflammation / Q000139:chemically induced / Q000517:prevention & control / Q000662:veterinary*; D016753:Interleukin-10 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000009:adverse effects; D008264:Macrophages / Q000378:metabolism; D009000:Monocytes / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D015398:Signal Transduction / Q000502:physiology*; D053773:Transforming Growth Factor beta1 / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D008070:Lipopolysaccharides; D016328:NF-kappa B; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10
keywords: Grass carp; IL-10; Inflammation regulation; Monocytes/macrophages; TGF-β1