Institut National de la Santé et de la Recherche Médicale, Université Paris XI, Le Kremlin-Bicêtre, France.
Am J Hematol. 2011 Feb;86(2):199-202. doi: 10.1002/ajh.21918.
β-Thalassemias are characterized by an imbalance of globin chains with an excess of α-chains which precipitates in erythroid precursors and red blood cells (RBCs) leading to inefficient erythropoiesis. The severity of the disease correlates with the amount of unpaired α-chains.Our goal was to develop a simple test for evaluation of the free α-hemoglobin pool present in RBC lysates. Alpha-Hemoglobin Stabilizing Protein (AHSP), the chaperone of α-Hb, was used to trap excess a-Hb. A recombinant GST-AHSP fusion protein was bound to an affinity micro-column and then incubated with hemolysates of patients. After washing, the α-Hb was quantified by spectrophotometry in the elution fraction. This assay was applied to 54 patients: 28 without apparent Hb disorder, 20 β-thalassemic and 6 α-thalassemic. The average value of free α-Hb pool was 93 ± 21 ppm (ng of free α-Hb per mg of Hb subunits)in patients without Hb disorder, while it varies from 119 to 1,756 ppm, in β-thalassemic patients and correlated with genotype. In contrast,the value of the free α-Hb pool was decreased in α-thalassemic patients (65 ± 26 ppm). This assay may help to characterize β-thalassemia phenotypes and to follow the evolution of the globin chain imbalance(α/β+γ ratio) in response to treatment.
β-地中海贫血的特征是珠蛋白链失衡，过量的α-链在红系前体细胞和红细胞（RBC）中沉淀，导致红细胞生成效率低下。疾病的严重程度与未配对的α-链数量相关。我们的目标是开发一种简单的测试方法，用于评估 RBC 裂解物中游离的α-血红蛋白池。α-血红蛋白稳定蛋白（AHSP）是α-Hb 的伴侣蛋白，用于捕获过量的α-Hb。重组 GST-AHSP 融合蛋白与亲和微柱结合，然后与患者的溶血物孵育。洗涤后，通过分光光度法在洗脱部分定量α-Hb。该测定法应用于 54 名患者：28 名无明显血红蛋白紊乱患者，20 名β-地中海贫血患者和 6 名α-地中海贫血患者。无血红蛋白紊乱患者的游离α-Hb 池平均为 93 ± 21 ppm（游离α-Hb 每毫克 Hb 亚基的 ng），而β-地中海贫血患者的游离α-Hb 池范围从 119 到 1756 ppm，与基因型相关。相比之下，α-地中海贫血患者的游离α-Hb 池值降低（65 ± 26 ppm）。该测定法可能有助于表征β-地中海贫血表型，并跟踪珠蛋白链失衡（α/β+γ 比值）在治疗反应中的变化。
