siRNA-mediated reduction of alpha-globin results in phenotypic improvements in beta-thalassemic cells.
beta-thalassemia is an inherited hemoglobinopathy caused by defective synthesis of the beta-globin chain of hemoglobin, leading to imbalanced globin chain synthesis. Excess alpha-globin precipitates in erythroid progenitor cells resulting in cell death, ineffective erythropoiesis and severe anemia. Decreased alpha-globin synthesis leads to milder symptoms, exemplified in individuals who co-inherit alpha- and beta-thalassemia. In this study, we investigated the feasibility of utilizing short-interfering RNA (siRNA) to mediate reductions in alpha-globin expression. A number of siRNA sequences targeting murine alpha-globin were tested in hemoglobinized murine erythroleukemic cells. One highly effective siRNA sequence (si-alpha 4) was identified and reduced alpha-globin by approximately 65% at both the RNA and the protein level. Electroporation of si-alpha 4 into murine thalassemic primary erythroid cultures restored alpha :beta-globin ratios to balanced wild-type levels and resulted in detectable phenotypic correction. These results indicate that siRNA-mediated reduction of alpha-globin has potential therapeutic applications in the treatment of beta-thalassemia.
Cell and Gene Therapy Research Group, The Murdoch Children's Research Institute, The University of Melbourne, Royal Children's Hospital, Flemington Road, Parkville 3052, Melbourne, Australia.
Hsiao Phin Joanna
HP
Voon
Hady
H
Wardan
Jim
J
Vadolas
D000818:Animals; D016923:Cell Death; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D005914:Globins / Q000172:deficiency / Q000235:genetics*; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000097:blood; D051379:Mice; D018345:Mice, Knockout; D010641:Phenotype; D016133:Polymerase Chain Reaction; D034741:RNA, Small Interfering / Q000235:genetics* / Q000627:therapeutic use; D017086:beta-Thalassemia / Q000097:blood* / Q000235:genetics / Q000473:pathology / Q000628:therapy
D034741:RNA, Small Interfering; D005914:Globins