Functions of TNF-α1 and TNF-α2 in large yellow croaker (Larimichthys crocea) in monocyte/macrophage activation

Mingyue Huang; Pengfei Mu; Xiaofeng Li; Qiulei Ren; Xiang-Yang Zhang; Yinnan Mu; Xinhua Chen

doi:10.1016/j.dci.2019.103576

Functions of TNF-α1 and TNF-α2 in large yellow croaker (Larimichthys crocea) in monocyte/macrophage activation

Dev Comp Immunol. 2020 Apr:105:103576. doi: 10.1016/j.dci.2019.103576. Epub 2019 Dec 14.

Authors

Mingyue Huang¹, Pengfei Mu², Xiaofeng Li¹, Qiulei Ren¹, Xiang-Yang Zhang¹, Yinnan Mu¹, Xinhua Chen³

Affiliations

¹ Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
² Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361102, China.
³ Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China. Electronic address: chenxinhua@tio.org.cn.

PMID: 31846686
DOI: 10.1016/j.dci.2019.103576

Abstract

Tumor necrosis factor-α (TNF-α) plays crucial roles in cell development, proliferation, apoptosis, inflammation, and immunity. TNF-α genes have been identified in various fish species, however, their biological functions remain to be further clarified. In this study, we identified a novel TNF-α homologue (LcTNF-α2) from large yellow croaker (Larimichthys crocea), which shares a low amino acid sequence identity to the previously reported large yellow croaker TNF-α (LcTNF-α1). The open reading frame of LcTNF-α2 is 714 nucleotides long, encoding a peptide of 237 amino acids (aa). The deduced LcTNF-α2 protein contains a 23-aa transmembrane region, a TACE restriction site at residues T⁷¹/L⁷², a TNF family signature (I¹⁰⁸- F¹³⁵), and two conserved cysteine residues (C³⁹ and C¹⁷⁹), as found in other known TNF-α sequences. Both LcTNF-α1 and LcTNF-α2 genes were constitutively expressed in all examined tissues and significantly up-regulated in the spleen and head kidney by Vibrio alginolyticus. Their transcripts were also detected in primary head kidney monocytes/macrophages (MO/Mϕs), lymphocytes (PKLs), granulocytes (PKGs), and large yellow croaker head kidney (LYCK) cell line and significantly increased in these cell types by inactivated Vibrio alginolyticus. Recombinant LcTNF-α1 and LcTNF-α2 proteins (rLcTNF-α1 and rLcTNF-α2) produced in Pichia pastoris not only significantly increased the production of reactive oxygen species (ROS), but also promoted the expression of proinflammatory cytokines (IL-1β, IL-6,IL-8, and TNF-α1) in MO/Mϕs from large yellow croaker. Even more, after stimulation with rLcTNF-α1 and rLcTNF-α2, the production of nitrogen oxide (NO) and the expression of inducible NO synthase (iNOS) gene were significantly up-regulated. However, only rLcTNF-α1 remarkedly enhanced the phagocytosis of MO/Mϕs and increased the expression of TNF-α2 in MO/Mϕs. These results therefore indicated that LcTNF-α1 and LcTNF-α2 both play roles in promoting activation of head kidney MO/Mϕs.

Keywords: Inflammatory response; Large yellow croaker (Larimichthys crocea); MO/Mϕs activation; TNF-α1; TNF-α2.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Cytokines / metabolism
Fish Proteins / genetics*
Immunity, Innate
Macrophage Activation / genetics
Macrophages / immunology*
Monocytes / immunology*
Perciformes / immunology*
Phylogeny
Sequence Alignment
Sequence Homology, Nucleic Acid
Transcriptome
Tumor Necrosis Factor-alpha / genetics*
Vibrio Infections / immunology*
Vibrio alginolyticus / physiology*

Substances

Cytokines
Fish Proteins
Tumor Necrosis Factor-alpha