Mahoney J F, Urakaze M, Hall S, DeGasperi R, Chang H M, Sugiyama E, Warren C D, Borowitz M, Nicholson-Weller A, Rosse W F
Department of Medicine, Duke University, Durham, NC.
Blood. 1992 Mar 15;79(6):1400-3.
To investigate the biosynthesis of the glycosylphosphatidylinositol (GPI) anchor in the granulocytes of paroxysmal nocturnal hemoglobinuria (PNH), the glycolipids of granulocytes from PNH patients and normal volunteers were biosynthetically labeled with [3H]mannose in the presence of tunicamycin. Extracted glycolipids were examined by thin-layer chromatography and compared with known biosynthetic intermediates. Normal granulocytes consistently showed [3H]mannose incorporation into the complete GPI core, several GPI biosynthetic intermediates, and dolichol phosphate mannose (DPM). The granulocytes of 10 patients with PNH that had no expression of CD55 and CD59 on greater than 95% of the cells were able to incorporate [3H]mannose into DPM, but were not able to incorporate detectable amounts into the complete GPI core. THus, PNH granulocytes do not synthesize detectable amounts of the complete GPI core and this defect likely accounts for the absence of GPI-linked membrane proteins on hematopoietic cells in this syndrome.
为研究阵发性睡眠性血红蛋白尿（PNH）患者粒细胞中糖基磷脂酰肌醇（GPI）锚的生物合成，在衣霉素存在的情况下，用[3H]甘露糖对PNH患者和正常志愿者的粒细胞糖脂进行生物合成标记。提取的糖脂通过薄层色谱法进行检测，并与已知的生物合成中间体进行比较。正常粒细胞始终显示[3H]甘露糖掺入完整的GPI核心、几种GPI生物合成中间体和磷酸多萜醇甘露糖（DPM）中。10例PNH患者的粒细胞中，超过95%的细胞不表达CD55和CD59，这些粒细胞能够将[3H]甘露糖掺入DPM，但无法将可检测量的[3H]甘露糖掺入完整的GPI核心。因此，PNH粒细胞无法合成可检测量的完整GPI核心，这种缺陷可能是该综合征造血细胞上缺乏GPI连接膜蛋白的原因。
