Annexins I and II bind to lipid A: a possible role in the inhibition of endotoxins.
Annexins I and II bind to lipid A: a possible role in the inhibition of endotoxins.
复制标题
膜联蛋白 I 和 II 与脂质 A 结合：可能在抑制内毒素中发挥作用。
DOI：
10.1042/bj3300067
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Vandenberg,SR
中科院分区：
文献类型：
--
作者：
Eberhard,DA;Vandenberg,SR
膜联蛋白是具有抗炎特性的 Ca2+ 依赖性磷脂结合蛋白，存在于某些细胞类型（例如白细胞和分泌上皮细胞）的表面并从其释放。本研究调查了膜联蛋白可能直接与细菌内毒素结合，抑制其与细胞受体或辅助结合蛋白相互作用的可能性。酶联免疫测定表明，低纳摩尔浓度的膜联蛋白-I 和膜联蛋白-II p36/p11 异四聚体与脂质 A 存在钙依赖性结合。相反，在类似条件下检测到很少或没有膜联蛋白与脂多糖 (LPS) 的结合。 LPS 结合蛋白与脂质 A 的结合被膜联蛋白-I 阻断，并且膜联蛋白抑制脂质 A 诱导的 RAW 264.7 细胞中亚硝酸盐的生成，但不抑制 LPS 诱导的亚硝酸盐生成。数据表明，膜联蛋白与脂质 A 的直接结合可能代表了抑制细胞和全身对内毒素反应的机制。
Annexins are Ca2+-dependent phospholipid-binding proteins with anti-inflammatory properties that are present on the surfaces of, and released from, certain cell types, such as leukocytes and secretory epithelia. The present study investigated the possibility that annexins may bind directly to bacterial endotoxin, inhibiting its interactions with cellular receptors or accessory binding proteins. An enzyme-linked immunoassay demonstrated calcium-dependent binding of low nanomolar concentrations of annexin-I and annexin-II p36/p11 heterotetramer to lipid A. In contrast, little or no annexin binding to lipopolysaccharide (LPS) was detected under similar conditions. LPS-binding protein binding to lipid A was blocked by annexin-I, and the annexins inhibited nitrite generation in RAW 264.7 cells induced by lipid A but not that induced by LPS. The data suggest that direct binding of annexins to lipid A may represent a mechanism for suppressing cellular and systemic responses to endotoxin.