Multilineage glycosylphosphatidylinositol anchor-deficient haematopoiesis in untreated aplastic anaemia
Multilineage glycosylphosphatidylinositol anchor-deficient haematopoiesis in untreated aplastic anaemia
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DOI：
10.1046/j.1365-2141.2001.03127.x
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发表时间：
2001-11-01
影响因子：
6.5
通讯作者：
Brodsky, RA
中科院分区：
文献类型：
--
作者：
Mukhina, GL;Buckley, JT;Brodsky, RA
再生障碍性贫血和阵发性睡眠性血红蛋白尿（PNH）是密切相关的疾病。在PNH中，含有PIGA突变的造血干细胞产生不能合成糖基磷脂酰肌醇（GPI）锚的血液成分。因为GPI锚是通道形成蛋白气溶素的受体。PNH细胞不结合毒素，不受溶解正常细胞的浓度的影响。利用这些生物学差异，我们已经开发了两种新的气溶素为基础的检测小群体的PNH细胞。当细胞用气溶素预处理以富集PNH群体时，可以检测到小至总红细胞的0.004%的CD59群体。所有PNH患者显示CD59缺陷型红细胞，但骨髓增生异常综合征（MDS）患者或对照组在气溶素富集前后均未检测到PNH细胞。只有1例再生障碍性贫血患者在暴露于气溶素前可检测到PNH红细胞。然而，14例（61%）在气溶素富集后可检测到PNH细胞。使用结合正常细胞上许多蛋白质的GPI锚的无活性荧光气单胞菌溶素原变体（FLAER）来检测粒细胞上的全局GPI锚缺陷。FLAER流式细胞仪检测结果显示，18例再生障碍性贫血患者中有12例（67%）有FLAER阴性的粒细胞，但MDS患者和正常对照组均无GPI锚定缺陷细胞。这些研究表明，气溶素为基础的检测可以揭示以前无法检测到的多谱系PNH细胞在未经治疗的再生障碍性贫血患者。因此。克隆性似乎是再生障碍性贫血的早期特征。
Aplastic anaemia and paroxysmal nocturnal haemoglobinuria (PNH) are closely related disorders. In PNH, haematopoietic stem cells that harbour PIGA mutations give rise to blood elements that are unable to synthesize glycosylphosphatidylinositol (GPI) anchors. Because the GPI anchor is the receptor for the channel-forming protein aerolysin. PNH cells do not bind the toxin and are unaffected by concentrations that lyse normal cells. Exploiting these biological differences, we have developed two novel aerolysin-based assays to detect small populations of PNH cells. CD59 populations as small as 0.004% of total red cells could be detected when cells were pretreated with aerolysin to enrich the PNH population. All PNH patients displayed CD59-deficient erythrocytes, but no myelodysplastic syndrome (MDS) patient or control had detectable PNH cells before or after enrichment in aerolysin. Only one aplastic anaemia patient had detectable PNH red cells before exposure to aerolysin. However, 14 (61%) had detectable PNH cells after enrichment in aerolysin. The inactive fluorescent proaerolysin variant (FLAER) that binds the GPI anchors of a number of proteins on normal cells was used to detect a global GPI anchor deficit on granulocytes. Flow cytometry with FLAER showed that 12 out of 18 (67%) aplastic anaemia patients had FLAER-negative granulocytes, but none of the MDS patients or normal control subjects had GPI anchor-deficient cells. These studies demonstrate that aerolysin-based assays can reveal previously undetectable multilineage PNH cells in patients with untreated aplastic anaemia. Thus. clonality appears to be an early feature of aplastic anaemia.