The immunomodulation of a novel tumor necrosis factor (CgTNF-1) in oyster Crassostrea gigas

• Published in: Developmental & Comparative Immunology
• Main Authors: Sun, Ying, Zho, Zhi, Wang, Lingling, Yang, Chuanyan, Jianga, Shuai, Song, Linsheng, Wang, LL (reprint author), Chinese Acad Sci, Inst Oceanol, 7 Nanhai Rd, Qingdao 266071, Peoples R China.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2014
• Subjects: Tumor Necrosis Factor; Immunomodulation; Apoptosis; Phagocytosis; Oyster; Immunology; Zoology; Crassostrea gigas
• Online Access: http://ir.qdio.ac.cn/handle/337002/24178; https://doi.org/10.1016/j.dci.2014.03.007

Tumor necrosis factor (TNF) is one of the most important cytokines involved in many processes in both vertebrate and invertebrate. In the present study, a new tumor necrosis factor with a typical TNF domain was identified in oyster Crassostrea gigas (designated CgTNF-1). CgTNF-1 shared low sequence identity and similarity with the TNF superfamily members from other vertebrate and invertebrate. After LPS stimulation, the mRNA expression of CgTNF-1 in haemocytes increased significantly and peaked at 12 h (1.39 +/- 0.12, P < 0.05) post treatment, and the expression of CgTNF-1 protein in haemolymph also increased obviously during 6-12 h. When the oyster haemocytes were incubated with rCgTNF-1, its apoptosis and phagocytosis rate were both effectively induced and peaked at 12 h post the treatment of rCgTNF-1 with the concentration of 100 ng mL(-1) (23.3 +/- 3%, P < 0.01), 50 ng mL(-1) (5.3 +/- 0.6%, P < 0.05) and 10 ng mL(-1) (6.7 +/- 1.2%, P < 0.05), respectively. After the co-stimulation of LPS and rCgTNF-1, the apoptosis and phagocytosis rate of oyster haemocytes, and the activities of PO and lysozyme in the haemolymph all increased significantly, and reached the peak at 12 h (apoptosis rate 26.7 +/- 1.5%, P < 0.01), 12 h (phagocytosis rate 8.3 +/- 0.6%, P < 0.01), 6h (PO 1.11 +/- 0.01 U mg prot(-1), P < 0.01) and 12h (lysozyme 168.9 +/- 8.3 U mg prot(-1), P < 0.05), respectively, which were significantly higher than that in the LPS group. Furthermore, the antibacteria activity in the LPS + TNF group was significantly higher than that in the LPS group during 612 h. All the results collectively indicated that CgTNF-1 was involved in the oyster immunity and played a crucial role in the modulation of immune response including apoptosis and phagocytosis of haemocytes, and regulation of antibacterial activity as well as the activation of immune relevant enzymes. (C) 2014 Elsevier Ltd. All rights reserved.