TLR9，先天免疫中重要的抗微生物受体

先天免疫系统是宿主抵御外来微生物入侵的第一道防线，TLR9是先天免疫系统中识别细菌和病毒CpGDNA的主要受体。TLR9信号转导利用MyD88依赖途径．在IRAK-4、IRAK-1、TRAF6和TAKl等关键信号蛋白的协同作用下．激活NF-KB和MAP途径，诱导产生一系列促炎细胞因子和趋化因子，最终引起Thl样炎症反应。TLR9除了有抗感染作用，还与自身免疫紊乱和一些恶性肿瘤发生相关。研究TLR9能帮助了解相关疾病发病机理及寻求预防和治疗的手段。

TLR9, the Important Antimicrobial Receptor in Innate Immunity

Innate immune of the host is the first defense against the invading microorganisms. TLR9 has been i- dentified as the main receptor in innate immunity for CpG DNA from bacterias and virus. The signals induced by TLILO use MyD88 dependent pathway, Once TLR9 is stimulated, associated by some key signal proteins, such as IRAK -4, IRAK - 1, TRAF6 , TAK1 etc, the NF - KB pathway and MAP pathway will be activated. Lat- er it will elevate the serum pro -inflammatory cytokines level, which we call Thl -like response. Besides anti -infection, TLR9 has also been implicated to play a role in autoimmune disorders and tumors. Studies on TLR9 can help discover mechanisms of some related diseases, and search for therapies and ways to prevent these diseases.