Wen Daihua, Wang Xialu, Shang Lei, Huang Yu, Li Tienan, Wu Chunfu, Zhang Rong, Zhang Jinghai
School of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, China.
School of Medical Devices, Shenyang Pharmaceutical University, China.
Dev Comp Immunol. 2016 Dec;65:124-131. doi: 10.1016/j.dci.2016.07.001. Epub 2016 Jul 4.
Apolipophorin-III (apoLp-III) is an exchangeable apolipoprotein found in many insect species and functions as a lipid transport vehicle. Recent studies have shown that apoLp-III is a multifunctional molecule involved in not only lipid transportation but also innate immune responses. In the present study, the pattern recognition properties of Antheraea pernyi apoLp-III were investigated. Recombinant Ap-apoLp-III was bound to different species of microbes and further study showed the rAp-apoLp-III is capable of interacting with pathogen associated molecular patterns (PAMPs) on the microbial cell surface. In addition, an Ap-apoLp-III/PAMP mixture stimulated the prophenoloxidase (PPO) activation of A. pernyi hemolymph in vitro, to a greater extent than PAMP alone while Ap-apoLp-III itself failed to activate the PPO system, indicating that Ap-apoLp-III up-regulates PPO activation by combining with PAMP. After pathogen invasion following an injection of Staphylococcus aureus, RNAi-mediated silencing of apoLp-III decreased the transcriptional abundance of three antimicrobial peptide genes. These data suggest that apoLp-III is a versatile pattern recognition receptor and may play important roles in the innate immune responses of Antheraea pernyi.
载脂蛋白-III（apoLp-III）是一种在许多昆虫物种中发现的可交换载脂蛋白，作为脂质运输载体发挥作用。最近的研究表明，apoLp-III是一种多功能分子，不仅参与脂质运输，还参与先天免疫反应。在本研究中，对柞蚕apoLp-III的模式识别特性进行了研究。重组Ap-apoLp-III与不同种类的微生物结合，进一步研究表明rAp-apoLp-III能够与微生物细胞表面的病原体相关分子模式（PAMP）相互作用。此外，Ap-apoLp-III/PAMP混合物在体外比单独的PAMP更能刺激柞蚕血淋巴的酚氧化酶原（PPO）激活，而Ap-apoLp-III本身未能激活PPO系统，表明Ap-apoLp-III通过与PAMP结合上调PPO激活。在注射金黄色葡萄球菌后病原体入侵后，RNAi介导的apoLp-III沉默降低了三种抗菌肽基因的转录丰度。这些数据表明，apoLp-III是一种多功能的模式识别受体，可能在柞蚕的先天免疫反应中发挥重要作用。
