Incompletely processed N-glycans of serum glycoproteins in congenital dyserythropoietic anaemia type II (HEMPAS).
Incompletely processed N-glycans of serum glycoproteins in congenital dyserythropoietic anaemia type II (HEMPAS).
复制标题
先天性红细胞生成障碍性贫血 II 型 (HEMPAS) 中血清糖蛋白加工不完全的 N-聚糖。
DOI：
10.1111/j.1365-2141.1992.tb06953.x
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发表时间：
1992
影响因子：
6.5
通讯作者：
Dell,A
中科院分区：
文献类型：
--
作者：
Fukuda,MN;Gaetani,GF;Izzo,P;Scartezzini,P;Dell,A
先天性促红细胞增生性贫血II型，或HEMPAS（遗传性红母细胞多核伴酸性血清溶解试验阳性）是一种由红细胞膜解体引起的遗传性疾病。这种疾病的主要缺陷在于基因编码酶(s)，该基因负责Asn - linked寡糖糖蛋白链的生物合成（Fukudaet al. 1990）。为了了解该基因缺陷是否影响红系细胞以外细胞的糖基化，我们分析了从HEMPAS患者血清中分离的转铁蛋白的碳水化合物结构。快速原子轰击质谱分析表明，HEMPAS转铁蛋白中存在高甘露糖型和杂化型低聚糖，而正常转铁蛋白中存在复配型低聚糖。结果强烈表明，HEMPAS肝细胞中Asn - linked寡糖链的生物合成受到干扰。结果，HEMPAS患者的血清糖蛋白与未完全加工的碳水化合物在血浆中循环。但它们一定是被肝脏细胞和网状内皮细胞吸收了。经大鼠静脉输注，高达30%的HEMPAS转铁蛋白从血浆循环中清除。大部分HEMPAS转铁蛋白被肝脏吸收，并且在肝细胞和Kupffer细胞中均有分布。大量异常糖基化的血清糖蛋白可能导致HEMPAS患者出现肝硬化和继发性组织铁沉着。
Congenital dyserythropoietic anaemia type II, or HEMPAS (hereditary erythroblastic multinuclearity with positive acidifed serum lysis test) is a genetic disease caused by membrane disorganization of erythroid cells. The primary defect of this disease lies in the gene encoding enzyme(s) which is responsible for the biosnythesis of Asn‐linked oligosacharides chains of glycoproteins (Fukudaet al. 1990). In order to know whether this gene defect affects the glycosylation in the cells other than the erythroid cells, the carbohydrate structures of the transferrin isolated from the sera of HEMPAS patients were analysed. Fast atom bombardment mass spectrometry analysis showed the presence of high mannose type and hybrid type oligosaccharides in the HEMPAS transferrin which is in contrast to the complex‐type oligosac charides found in the normal transferrin. The results strongly suggest that biosynthesis of Asn‐linked oligosaccharide chains in HEMPAS hepatocytes is disturbed. As a result, the serum glycoproteins with incompletely processed carbohydrates are circulating in the plasma in HEMPAS patients. but they must have been absorbed by the cells in the liver and the reticuloendothelial cells. Upon intravenous infusion into rats, as much as 30% of the HEMPAS transferrin was cleared from the plasma circulation. The majority of the HEMPAS transferrins was taken up by the liver, and transferrin was distributed both in the hepatocytes and the Kupffer cells. The presence of enormous amounts of aberrantly glycosylated serum glycoproteins may lead to the liver cirrhosis and secondary tissue siderosis seen in HEMPAS patients.