Opsonic character of the plasma proteins in phagocytosis-dependent host response to bacterial infection in a marine invertebrate, Crassostrea gigas

被引：7

作者：

Mao, Fan ^{[1
,2
,3
]}

Liu, Kunna ^{[1
,2
,4
]}

Bao, Yongbo ^{[5
]}

Lin, Yue ^{[1
,2
,4
]}

Zhang, Xiangyu ^{[1
,2
,4
]}

Xu, Duo ^{[1
,2
,4
]}

Xiang, Zhiming ^{[1
,2
,3
]}

Li, Jun ^{[1
,2
,3
]}

Zhang, Yang ^{[1
,2
,3
]}

Yu, Ziniu ^{[1
,2
,3
]}

机构：

[1] Chinese Acad Sci, South China Sea Inst Oceanol, Key Lab Trop Marine Bioresources & Ecol, Guangdong Prov Key Lab Appl Marine Biol, Guangzhou 510301, Peoples R China

[2] Chinese Acad Sci, Innovat Acad South China Sea Ecol & Environm Engn, Guangzhou 510301, Peoples R China

[3] Southern Marine Sci & Engn Guangdong Lab Guangzho, Guangzhou 510301, Peoples R China

[4] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[5] Zhejiang Wanli Univ, Coll Biol & Environm Sci, Zhejiang Key Lab Aquat Germplasm Resources, Ningbo 315100, Peoples R China

来源：

DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY | 2020年 / 106卷

基金：

美国国家科学基金会; 国家重点研发计划;

关键词：

Crassostrea gigas; Plasma proteins; Opsonins; Phagocytosis; Invertebrate immunity; PATTERN-RECOGNITION RECEPTORS; DOMAIN-CONTAINING PROTEIN; MANNAN-BINDING LECTIN; C1Q ACTS; OYSTER; COMPLEMENT; INTEGRIN; SELF; IDENTIFICATION; TRANSDUCTION;

D O I：

10.1016/j.dci.2019.103596

中图分类号：

S9 [水产、渔业];

学科分类号：

0908 ;

摘要：

Phagocytosis is an evolutionarily conserved immune response, whose efficiency is fundamentally coupled with opsonization of extracellular microbes. How marine mollusks cells recognize and selectively capture pathogens during phagocytosis to clear them is not completely understood. In this study, we observed that plasma is extremely effective for oyster hemocyte phagocytosis, so we investigated candidate proteins among plasma proteins with binding affinity for Vibrio parahaemolyticus in Pacific oyster (Crassostrea gigas) by subjecting them to mass spectroscopy analysis for protein identification and characterization, and address the complex regulatory network to engulf invaders. There were 620 identified proteins potentially associated with bacteria binding and phagocytosis which could be quantified. Our results showed that C1q and lectins identified in Pacific oyster plasma held binding ability to bacteria, clearly suggesting their potent to be opsonins. The dominant expressed plasma protein p1-CgC1q (Complement component 1q)-like protein was identified and its opsonic role was confirmed in this study. The cell surface receptor Cgintegrin interacts directly with p1-CgC1q to mediate phagocytosis. We further confirmed that the interaction between C1q and integrin not rely on the typical recognition site RGD but on the RGE. Evidence exist revealed that p1-CgC1q could coat bacteria via the endotoxin LPS (lipopolysaccharide) and subsequently bind the receptor integrin to significantly enhance hemocytic phagocytosis and bacteria clearance. This study has thus furnished clear evidence for the importance of plasma proteins in mollusk, shedding light on the humoral immunity and an underappreciated strategy in marine host-pathogen interactions.

引用

页数：12