Membrane receptors on rat hepatocytes for the inner core region of bacterial lipopolysaccharides.
Membrane receptors on rat hepatocytes for the inner core region of bacterial lipopolysaccharides.
复制标题
大鼠肝细胞上细菌脂多糖内核区域的膜受体。
DOI：
10.1016/s0021-9258(19)39789-3
复制
发表时间：
1990
期刊：
影响因子：
--
通讯作者：
J. Parent
中科院分区：
文献类型：
--
作者：
J. Parent
细菌脂多糖（LPS）是一种强效内毒素，被认为与革兰氏阴性菌败血症的发病机制有关。已知肝脏是负责从哺乳动物体循环中清除LPS的主要器官。在这项工作中，125 I-标记的LPS已被用于过滤试验的LPS的特异性结合完整的大鼠肝细胞。本研究中使用了从不同O-血清型的沙门氏菌和大肠杆菌中分离的8种具有完整O-特异性多糖链的S-型（光滑）LPS以及从其核心寡糖合成缺陷的沙门氏菌突变体中分离的9种R-型（粗糙）LPS。除Re外，所有125 I标记的S型LPS和R型LPS均与分离的肝细胞特异性结合。结合是可饱和的，被过量的未标记的同源或异源LPS抑制，但不被脂质A抑制，并且是胰蛋白酶敏感的。L-甘油-D-甘露庚糖（庚糖）是几乎所有LPS的内核区域的成分，是125 I标记的Rb 2 LPS的特异性结合的有效抑制剂，而其它单糖，包括3-脱氧-D-甘露-2-辛酮糖酸（KDO），具有弱的或可忽略的抑制剂活性。这些结果强烈表明，存在一个凝集素样受体的LPS内核区（庚糖KDO区）的大鼠肝细胞质膜上。
Bacterial lipopolysaccharides (LPS) are potent endotoxins that are thought to be involved in the pathogenesis of Gram-negative septicemia. The liver is known to be the primary organ responsible for the clearance of LPS from the systemic circulation in mammals. In this work, 125I-labeled LPS have been used in a filtration assay for the specific binding of LPS to intact rat hepatocytes. Eight S-form (smooth) LPS with complete O-specific polysaccharide chains isolated from different O-serotypes of Salmonella and Escherichia coli as well as nine R-form (rough) LPS isolated from Salmonella mutants deficient in synthesis of their core oligosaccharides were used in this study. All 125I-labeled S-form LPS and R-form LPS, except Re, show specific binding to isolated hepatocytes. The binding is saturable, is inhibited with excess unlabeled homologous or heterologous LPS but not lipid A, and is trypsin sensitive. L-Glycero-D-mannoheptose (heptose), a constituent of the inner core region of almost all LPS, is a potent inhibitor of the specific binding of 125I-labeled Rb2 LPS, whereas other monosaccharides, including 3-deoxy-D-manno-2-octulosonic acid (KDO), have weak or negligible inhibitor activity. These results strongly suggest the presence of a lectin-like receptor for the LPS inner core region (heptose-KDO region) on the plasma membrane of rat hepatocytes.