title: Endogenous molecules induced by a pathogen-associated molecular pattern (PAMP) elicit innate immunity in shrimp.
abstract: Invertebrates rely on an innate immune system to combat invading pathogens. The system is initiated in the presence of cell wall components from microbes like lipopolysaccharide (LPS), β-1,3-glucan (βG) and peptidoglycan (PG), altogether known as pathogen-associated molecular patterns (PAMPs), via a recognition of pattern recognition protein (PRP) or receptor (PRR) through complicated reactions. We show herein that shrimp hemocytes incubated with LPS, βG, and PG caused necrosis and released endogenous molecules (EMs), namely EM-L, EM-β, and EM-P, and found that shrimp hemocytes incubated with EM-L, EM-β, and EM-P caused changes in cell viability, degranulation and necrosis of hemocytes, and increased phenoloxidase (PO) activity and respiratory burst (RB) indicating activation of immunity in vitro. We found that shrimp receiving EM-L, EM-β, and EM-P had increases in hemocyte count and other immune parameters as well as higher phagocytic activity toward a Vibrio pathogen, and found that shrimp receiving EM-L had increases in proliferation cell ratio and mitotic index of hematopoietic tissues (HPTs). We identified proteins of EMs deduced from SDS-PAGE and LC-ESI-MS/MS analyses. EM-L and EM-P contained damage-associated molecular patterns (DAMPs) including HMGBa, HMGBb, histone 2A (H2A), H2B, and H4, and other proteins including proPO, Rab 7 GPTase, and Rab 11 GPTase, which were not observed in controls (EM-C, hemocytes incubated in shrimp salt solution). We concluded that EMs induced by PAMPs contain DAMPs and other immune molecules, and they could elicit innate immunity in shrimp. Further research is needed to identify which individual molecule or combined molecules of EMs cause the results, and determine the mechanism of action in innate immunity.
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Yu-Yuan
authors.initials: YY
authors.lastname: Chen
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Jiann-Chu
authors.initials: JC
authors.lastname: Chen
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Yong-Chin
authors.initials: YC
authors.lastname: Lin
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Suwaree
authors.initials: S
authors.lastname: Kitikiew
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Li
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Jia-Chin
authors.initials: JC
authors.lastname: Bai
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Kuei-Chi
authors.initials: KC
authors.lastname: Tseng
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Bo-Wei
authors.initials: BW
authors.lastname: Lin
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Po-Chun
authors.initials: PC
authors.lastname: Liu
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Yin-Ze
authors.initials: YZ
authors.lastname: Shi
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Yi-Hsuan
authors.initials: YH
authors.lastname: Kuo
authors.affiliation: The Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 202, Taiwan, Republic of China.
authors.forename: Yu-Hsuan
authors.initials: YH
authors.lastname: Chang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D015415:Biomarkers / Q000378:metabolism*; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D006434:Hemocytes / Q000187:drug effects / Q000276:immunology / Q000473:pathology*; D007113:Immunity, Innate / Q000187:drug effects / Q000276:immunology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008940:Mitotic Index; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000494:pharmacology*; D033561:Penaeidae / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology*; D051192:Receptors, Pattern Recognition / Q000378:metabolism*; D016897:Respiratory Burst / Q000187:drug effects / Q000276:immunology; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry; D014735:Vibrio Infections / Q000188:drug therapy / Q000276:immunology / Q000382:microbiology; D044149:Vibrio alginolyticus / Q000187:drug effects / Q000276:immunology
chemical_list: D015415:Biomarkers; D008070:Lipopolysaccharides; D000069452:Pathogen-Associated Molecular Pattern Molecules; D051192:Receptors, Pattern Recognition