Restoration of the balanced alpha/beta-globin gene expression in beta654-thalassemia mice using combined RNAi and antisense RNA approach

Hum Mol Genet. 2007 Nov 1;16(21):2616-25. doi: 10.1093/hmg/ddm218. Epub 2007 Aug 22.

Abstract

The beta-thalassemia is associated with abnormality in beta-globin gene, leading to imbalanced synthesis of alpha-/beta-globin chains. Consequently, the excessive free alpha-globin chains precipitate to the erythrocyte membrane, resulting in hemolytic anemia. We have explored post-transcriptional strategies aiming at alpha-globin reduction and beta-globin enrichment on beta(654) (Hbb(th-4)/Hbb(+)) mouse, carrying a human splicing-deficient beta-globin allele (Hbb(th-4)). Lentiviral vectors of short hairpin RNA (shRNA) targeting alpha-globin and/or antisense RNA facilitating beta-globin correct splicing were microinjected into beta(654) single-cell embryos. Three transgenic strains were generated, as alpha(i)-Hbb(th-4)/Hbb(+)(shRNA), beta(a)-Hbb(th-4)/Hbb(+)(antisense) and alpha(i)beta(a)-Hbb(th-4)/Hbb(+)(both shRNA and antisense). Without notable abnormalities, all the founders and their offsprings showed sustained amelioration of hematologic parameters, ineffective erythropoiesis and extramedullary hematopoiesis. Augmented effects appeared in alpha(i)beta(a)-Hbb(th-4)/Hbb(+), which correlated with a better-balanced alpha-/beta-globin mRNA level. Among the transgenic mice integrated with shRNA and antisense RNA, one homozygous mouse (Hbb(th-4)/Hbb(th-4)) had been viable, and the 3-week survival rate for heterozygotes (Hbb(th-4)/Hbb(+)) was 97%, compared with 45.4% for untreated. Our data have demonstrated the feasibility of techniques for beta-thalassemia therapy by balancing the synthesis of alpha-/beta-globin chains.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anemia / therapy
  • Animals
  • Bone Marrow / pathology
  • Erythropoiesis / genetics
  • Gene Expression
  • Genetic Therapy / methods*
  • Genetic Vectors / genetics
  • Globins / antagonists & inhibitors*
  • Globins / genetics
  • Hemoglobins / genetics
  • Humans
  • Lentivirus / genetics
  • Mice
  • Mice, Transgenic
  • Phenotype
  • RNA Splicing / genetics
  • RNA, Antisense / genetics*
  • RNA, Small Interfering / genetics*
  • beta-Thalassemia / therapy*

Substances

  • Hemoglobins
  • RNA, Antisense
  • RNA, Small Interfering
  • Globins