Effects of receptor-specific antibody on the uptake of desialylated glycoproteins in the isolated perfused rat liver.
Effects of receptor-specific antibody on the uptake of desialylated glycoproteins in the isolated perfused rat liver.
复制标题
受体特异性抗体对离体灌注大鼠肝脏中去唾液酸化糖蛋白摄取的影响。
DOI：
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发表时间：
1980
影响因子：
4.8
通讯作者：
A. Wolkoff
中科院分区：
文献类型：
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作者：
R. Stockert;U. Gärtner;A. Morell;A. Wolkoff
从大多数哺乳动物糖蛋白中去除末端唾液酸残基导致其从循环快速转移到肝脏中。在体外，这些去唾液酸化的糖蛋白与特异性膜相关肝凝集素结合，该凝集素在肝细胞内普遍存在。在本研究中，注射放射性标记的无唾液酸类粘蛋白或胆红素之前，将纯化的凝集素的特异性抗体输注到离体灌注大鼠肝脏的门静脉中，可使无唾液酸类粘蛋白流入肝脏的速率降低80%以上，而胆红素的流入量不变。尽管从灌注系统中去除过量抗体后，无唾液酸类粘蛋白的摄取仍被阻断至少90分钟，但功能性结合蛋白的总肝含量几乎正常。这些结果表明，与特定的细胞表面凝集素的相互作用是必不可少的，从循环中去除的无唾液酸orosomucoid。在输注抗体后的90分钟期间，没有功能性凝集素恢复到肝细胞表面。
Removal of the terminal sialic acid residues from most mammalian glycoproteins results in their rapid transfer from the circulation into the liver. In vitro, these desialylated glycoproteins bind to a specific membrane-associated hepatic lectin which has a ubiquitous distribution within the liver cell. In the present study, infusion of a specific antibody to the purified lectin into the portal vein of an isolated perfused rat liver prior to injection of radiolabeled asialoorosomucoid or bilirubin reduced the rate of influx of asialoorosomucoid into the liver by over 80%, while the influx of bilirubin was unchanged. Although uptake of asialoorosomucoid remained blocked for at least 90 min after excess antibody was removed from the perfusion system, the total hepatic content of functional binding protein was nearly normal. These results indicate that interaction with specific cell surface lectin is essential for removal of asialoorosomucoid from the circulation. During the 90 min following infusion of antibody, no functional lectin is restored to the surface of hepatocytes.