无脊椎动物先天免疫模式识别受体研究进展

Progress in Pattern Recognition Receptors of Innate Immunity in Invertebrates

免疫系统的基本功能是“自己”与“非己”识别 .对入侵物的识别是免疫防御的起始 ,最终引发效应物反应系统 ,包括吞噬作用、包被作用、激活蛋白酶级联反应和黑化作用以及诱导抗菌肽的合成等 ,从而清除或消灭入侵物 .研究证明 ,这种“非己”识别是因为存在某些特异性的、可溶的或与细胞膜结合的模式识别受体 ,可以识别或结合微生物表面保守的、而在宿主中又不存在的病原相关分子模式 .模式识别受体通过对病原相关分子的识别启动先天免疫防御 .近年来这方面的研究进展很快 ,已经在无脊椎动物中确定了多种模式识别受体 ,包括肽聚糖识别蛋白、含硫酯键蛋白、革兰氏阴性菌结合蛋白、清除受体、C型凝集素、硫依赖型凝集素、Toll样受体和血素等 。

Discrimination between self and non self is the basic function of innate immunity that is found in both vertebrates and invertebrates. A critical first step in any immune response is the recognition of an invading organism as foreign. In the innate immune systems of both vertebrates and invertebrates, such recognition, termed pattern recognition, is mediated by a group of proteins, known as pattern recognition proteins or receptors. Different pattern recognition proteins recognize and bind to molecules (pathogen associated molecular patterns, PAMPs) present on the surface of microorganisms but absent from animals. Binding of pattern recognition proteins to PAMPs triggers responses such as phagocytosis, nodule formation, encapsulation, activation of proteinase cascades, melanization and synthesis of antimicrobial peptides. The characterizations and functions of several classes of pattern recognition receptors involved in immune responses of the invertebrate, including peptidoglycan recognition proteins, thioester containing proteins, Gram negative binding proteins, scavenger receptors, C type lectins, galectins, Toll like receptors and hemolins were reviewed.