Stable expression in a Chinese hamster ovary (CHO) cell line of bioactive recombinant chelonianin, which plays an important role in protecting fish against pathogenic infection

• Published in: Developmental and comparative immunology Vol. 33; no. 1; pp. 117 - 126
• Main Authors: Chiou, Ming-Jyun, Chen, Lee-Kang, Peng, Kuan-Chieh, Pan, Chia-Yu, Lin, Tai-Lang, Chen, Jyh-Yih
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 2009
• Subjects: Animals; Anti-Infective Agents - metabolism; Antimicrobial peptide; Bacterial Infections - prevention & control; Bacterial Infections - veterinary; Chelonianin; CHO Cells; Cricetinae; Cricetulus; Fish Proteins - genetics; Fish Proteins - metabolism; Gene expression; Green fluorescent protein; Marine; Nitric Oxide Synthase Type I - biosynthesis; Oreochromis mossambicus; Penaeus monodon; Recombinant Proteins - metabolism; Tilapia; Tilapia - metabolism; Tilapia - microbiology; Tumor Necrosis Factor-alpha - biosynthesis; Vibrio; Vibrio harveyi; Vibrio harveyi; rcf protein; Green fluorescent protein; Tilapia; Penaeus monodon; Gene expression; Chelonianin; Antimicrobial peptide
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2008.07.012

Chelonianin, originally isolated from the shrimp ( Penaeus monodon), exhibits antimicrobial effects in vitro and in vivo and is used to treat infectious fish diseases. Herein, we report that the recombinant chelonianin protein fused to a fluorescent protein (rcf protein) was expressed from a stably transfected Chinese hamster ovary (CHO) cells. The in vitro experiments showed that the rcf protein exhibited antimicrobial activity against several bacteria, while the recombinant fluorescent protein alone did not. In addition, pretreatment and post-treatment with the rcf protein were both effective in promoting a significant decrease in fish mortality and decreasing the number of infectious bacteria. We utilized the quantitative reverse-transcriptase polymerase chain reaction technique to survey the levels of gene expressions of tumor necrosis factor-alpha (TNF-α) and nitric oxide synthase 1 induced in response to bacterial infection in experiments with tilapia ( Oreochromis mossambicus). Our results indicated that the rescue of fish treated with the rcf protein may involve regulation of TNF-α expression. Collectively, chelonianin inhibited the production of an inflammatory mediator and reduced mortality in fish during bacterial challenge, suggesting that it has potential as a therapeutic or prophylactic drug for use against bacterial infectious diseases.