High mobility group box 1 protein interacts with multiple Toll-like receptors
High mobility group box 1 protein interacts with multiple Toll-like receptors
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DOI：
10.1152/ajpcell.00401.2005
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发表时间：
2006-03-01
影响因子：
5.5
通讯作者：
Abraham, E
中科院分区：
文献类型：
--
作者：
Park, JS;Gamboni-Robertson, F;Abraham, E
高迁移率族蛋白B1（HMGB1）最初被描述为一种DNA结合蛋白，也可被释放到细胞外，并作为炎症反应的晚期介质发挥作用。尽管最近的报道表明晚期糖基化终末产物受体（RAGE）以及Toll样受体2（TLR2）和Toll样受体4（TLR4）参与了HMGB1对细胞的激活，但几乎没有证据表明HMGB1与这些受体之间存在直接关联。为了研究这一问题，我们使用荧光共振能量转移（FRET）和免疫沉淀技术直接研究HMGB1与TLR2、TLR4和RAGE在细胞表面的相互作用。RAW264.7巨噬细胞的FRET图像显示HMGB1与TLR2和TLR4相关联，但与RAGE无关。对人胚胎肾293细胞进行瞬时转染表明，HMGB1通过TLR2或TLR4而非RAGE诱导细胞激活和核因子κB（NF - κB）依赖的转录。免疫共沉淀也发现HMGB1与TLR2以及TLR4之间存在相互作用，但与RAGE无相互作用。这些研究首次提供了直接证据，表明HMGB1可与TLR2和TLR4相互作用，也为HMGB1诱导细胞激活并产生类似于脂多糖（LPS）引发的炎症反应的能力提供了解释。
High mobility group box 1 (HMGB1), originally described as a DNA-binding protein, can also be released extracellularly and functions as a late mediator of inflammatory responses. Although recent reports have indicated that the receptor for advanced glycation end products ( RAGE) as well as Toll-like receptor (TLR)2 and TLR4 are involved in cellular activation by HMGB1, there has been little evidence of direct association between HMGB1 and these receptors. To examine this issue, we used fluorescence resonance energy transfer (FRET) and immunoprecipitation to directly investigate cell surface interactions of HMGB1 with TLR2, TLR4, and RAGE. FRET images in RAW264.7 macrophages demonstrated association of HMGB1 with TLR2 and TLR4 but not RAGE. Transient transfections into human embryonic kidney-293 cells showed that HMGB1 induced cellular activation and NF-B-K-dependent transcription through TLR2 or TLR4 but not RAGE. Coimmunoprecipitation also found interaction between HMGB1 and TLR2 as well as TLR4, but not with RAGE. These studies provide the first direct evidence that HMGB1 can interact with both TLR2 and TLR4 and also supply an explanation for the ability of HMGB1 to induce cellular activation and generate inflammatory responses that are similar to those initiated by LPS.