Two antibacterial C-type lectins from crustacean, Eriocheir sinensis, stimulated cellular encapsulation in vitro

• Published in: Developmental and comparative immunology 2013-12, Vol.41 (4), p.544-552
• Main Authors: Jin, Xing-Kun, Li, Shuang, Guo, Xiao-Nv, Cheng, Lin, Wu, Min-Hao, Tan, Shang-Jian, Zhu, You-Ting, Yu, Ai-Qing, Li, Wei-Wei, Wang, Qun
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Anti-Bacterial Agents - immunology; Anti-Bacterial Agents - metabolism; Antibacterial activity; Chinese mitten crab; Crustacea - genetics; Crustacea - immunology; Crustacea - metabolism; Decapoda; Encapsulation; Eriocheir sinensis; Hemocytes; Immunity, Innate - immunology; Lectins, C-Type - genetics; Lectins, C-Type - immunology; Lectins, C-Type - metabolism; Receptors, Pattern Recognition - genetics; Receptors, Pattern Recognition - immunology; Receptors, Pattern Recognition - metabolism; Sequence Alignment
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2013.07.016

•Both rEsLecA and rEsLecG could bind towards wide range of microorganisms.•Both rEsLecA and rEsLecG induced the aggregation against microbial pathogens.•Both rEsLecA and rEsLecG exhibited microbial inhibition and even bactericidal activity.•Both rEsLecA and rEsLecG could stimulate the cellular encapsulation in vitro. The first step of host fighting against pathogens is that pattern recognition receptors recognized pathogen-associated molecular patterns. However, the specificity of recognition within the innate immune molecular of invertebrates remains largely unknown. In the present study, we investigated how invertebrate pattern recognition receptor (PRR) C-type lectins might be involved in the antimicrobial response in crustacean. Based on our previously obtained completed coding regions of EsLecA and EsLecG in Eriocheir sinensis, the recombinant EsLectin proteins were produced via prokaryotic expression system and affinity chromatography. Subsequently, both rEsLecA and rEsLecG were discovered to have wide spectrum binding activities towards microorganisms, and their microbial-binding was calcium-independent. Moreover, the binding activities of both rEsLecA and rEsLecG induced the aggregation against microbial pathogens. Both microorganism growth inhibitory activities assays and antibacterial activities assays revealed their capabilities of suppressing microorganisms growth and directly killing microorganisms respectively. Furthermore, the encapsulation assays signified that both rEsLecA and rEsLecG could stimulate the cellular encapsulation in vitro. Collectively, data presented here demonstrated the successful expression and purification of two C-type lectins proteins in the Chinese mitten crab, and their critical role in the innate immune system of an invertebrate.