urc mondor

Unité de Recherche Clinique Henri Mondor

Red blood cells free α-haemoglobin pool: a biomarker to monitor the β-thalassemia intermedia variability. The ALPHAPOOL study.

Vasseur C, Domingues-Hamdi E, Ledudal K, Le Corvoisier P, Barau C, Ghaleh B, Rialland A, Pissard S, Galactéros F, Baudin-Creuza V Br J Haematol. 2017;179(1):142-153.

<p>The severity of β-thalassaemia (β-thal) intermedia is mainly correlated to the degree of imbalanced α/non α-globin chain synthesis. The phenotypic diversity of β-thal depends on this imbalance and reflects all possible combinations of α- and β-globin genotypes, levels of fetal haemoglobin (HbF) and co-inheritance of other modulating factors. This study aimed to demonstrate the validity of a new surrogate of α/non α-globin biosynthetic ratio by measuring the soluble α-Hb pool in lysed red blood cells. Our results confirm that the α-Hb pool measurement allows a good discrimination between β-thal intermedia patients, controls and α-thal patients (P < 0·003). Receiver operator characteristic analyses revealed an area under the curve of 0·978 for the α-Hb pool measurement at a threshold of 120 ng free α-Hb/mg of total Hb/ml of haemolysate (ppm) with a sensitivity and specificity of 86% and 100%, respectively, to discriminate between β-thal and not β-thal subjects. Significant correlations were observed between the α-Hb pool and biological parameters of β-thal, the most significant association being observed with red cell hexokinase activity. This study indicates that the α-Hb pool could be a new marker for assistance in diagnostic orientation of β-thal intermedia patients and may be clinically useful for monitoring the evolution of the disequilibrium of globin synthesis in response to treatments.</p>

MeSH terms: Adolescent; Adult; Aged; alpha-Globins; alpha-Thalassemia; beta-Globins; beta-Thalassemia; Biomarkers; Case-Control Studies; Erythrocytes; Female; France; Genotype; Hematologic Tests; Humans; Male; Middle Aged; Mutation; Reproducibility of Results; Sensitivity and Specificity; Young Adult
DOI: 10.1111/bjh.14800