Specific endotoxic lipopolysaccharide-binding proteins on murine splenocytes. II. Membrane localization and binding characteristics.
Specific endotoxic lipopolysaccharide-binding proteins on murine splenocytes. II. Membrane localization and binding characteristics.
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DOI：
10.4049/jimmunol.141.3.1006
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发表时间：
1988-08
影响因子：
4.4
通讯作者：
M. Lei;D. Morrison
中科院分区：
文献类型：
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作者：
M. Lei;D. Morrison
我们已经描述了LPS与80 kda的LPS结合蛋白的结合，通过LPS光亲和探针检测到存在于小鼠脾细胞上。LPS与80 kda蛋白的特异性结合在低浓度下与LPS浓度成正比，在高浓度下是饱和的。结合被同源和异源未分化的LPS以及无多糖脂质A抑制，表明LPS的生物活性成分具有特异性。结合动力学分析表明，在前15分钟有时间依赖性的增加，但在此之后没有检测到增加。脂多糖与80 kda脂多糖结合蛋白的结合减少，但在叠氮化物存在的情况下，在4℃时仍容易检测到。80 kda的lps结合蛋白存在于小鼠脾细胞分离的细胞质膜中，并通过辛基葡萄糖苷从完整的脾细胞中释放，这表明这种lps结合蛋白是膜定位的。结果与80 kda lps结合蛋白作为脂质a特异性膜受体的身份一致，但并没有明确确定。
We have characterized the binding of LPS to an 80-kDa LPS-binding protein detected by an LPS photoaffinity probe to be present on murine splenocytes. Specific binding of LPS to the 80-kDa protein is directly proportional to LPS concentration at low concentrations of LPS and is saturable at high concentrations of LPS. Binding is inhibited by both homologous and heterologous underivatized LPS as well as by polysaccharide-free lipid A, indicating a specificity for the biologically active component of LPS. Analysis of the kinetics of binding indicate a time-dependent increase over the first 15 min, but increases are not detected after this time. Binding of LPS to the 80-kDa LPS-binding protein is reduced but still readily detectable at 4 degrees C in the presence of azide. The presence of the 80-kDa LPS-binding protein in an isolated cytoplasmic membrane fraction of murine splenocytes as well as its release from intact splenocytes by octylglucoside suggest that this LPS-binding protein is membrane localized. The results are consistent with, but do not establish unequivocally, the identity of the 80-kDa LPS-binding protein as a specific membrane receptor for lipid A.