OBJECTIVETo study the effect of liposomal transfection of antisense oligonucleotide (ASON) on the erythroid cell alpha-globin gene in the patients with severe beta-thalassemia, and provide a new idea for beta-thalassemia gene therapy.

METHODSA highly effective ASON targeting alpha-globin gene was transfected into severe beta-thalassemic erythroid cells cultured in vitro by liposomal at an optimal concentration. The expression level of alpha, beta, gamma-globin gene, the level of hemoglobin, and the excess alpha-globin chains precipitates in ASON group and control group were carefully analyzed by quantitative real-time PCR(Q-RT-PCR), high performance liquid chromatography (HPLC), and electron microscope, respectively.

RESULTSThe mRNA expression of alpha-globin gene was significantly lower in ASON group (9.04 +/- 0.29) than in control group (24.23 +/- 0.29) (P<0.01). Simultaneously, the disequilibrium between alpha- and beta-, gamma-globin gene expression was partly modified by ASON, the ratios of ASON group and control group being 0.79 +/- 0.02 and 2.26 +/- 0.06 respectively (P<0.01). HPLC demonstrated that the levels of HbA2 and HbF increased with downregulation of alpha-globin gene in beta-thalassemic erythroid cells, particularly HbF. The precipitates of alpha-globin chains in ASON group were lessened under electron microscope, particularly in early erythroblast while no change in the control group.

CONCLUSIONThe high effective ASON contributes to inhibit the alpha-globin gene expression of severe beta-thalassemic erythroid cells, partly modify the disequilibrium between alpha-, beta- and gamma-globin gene expression and obviously reduce the precipitates of alpha-globin chains in erythroid cells. It might provide a new idea for gene therapy of beta-thalassemia.