A capsid-modified helper-dependent adenovirus vector containing the beta-globin locus control region displays a nonrandom integration pattern and allows stable, erythroid-specific gene expression

J Virol. 2005 Sep;79(17):10999-1013. doi: 10.1128/JVI.79.17.10999-11013.2005.

Abstract

Gene therapy for hemoglobinopathies requires efficient gene transfer into hematopoietic stem cells and high-level erythroid-specific gene expression. Toward this goal, we constructed a helper-dependent adenovirus vector carrying the beta-globin locus control region (LCR) to drive green fluorescent protein (GFP) expression, whereby the LCR-GFP cassette is flanked by adeno-associated virus (AAV) inverted terminal repeats (Ad.LCR-beta-GFP). This vector possesses the adenovirus type 35 fiber knob that allows efficient infection of hematopoietic cells. Transduction and vector integration studies were performed in MO7e cells, a growth factor-dependent CD34(+) erythroleukemic cell line, and in cord blood-derived human CD34(+) cells. Stable transduction of MO7e cells with Ad.LCR-beta-GFP was more efficient and less subject to position effects and silencing than transduction with a vector that did not contain the beta-globin LCR. Analysis of integration sites indicated that Ad.LCR-beta-GFP integration in MO7e cells was not random but tethered to chromosome 11, specifically to the globin LCR. More than 10% of analyzed integration sites were within the chromosomal beta-globin LCR. None of the Ad.LCR-beta-GFP integrations occurred in exons. The integration pattern of a helper-dependent vector that contained X-chromosomal stuffer DNA was different from that of the beta-globin LCR-containing vector. Infection of primary CD34(+) cells with Ad.LCR-beta-GFP did not affect the clonogenic capacity of CD34(+) cells. Transduction of CD34(+) cells with Ad.LCR-beta-GFP resulted in vector integration and erythroid lineage-specific GFP expression.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviridae / genetics*
  • Adenoviridae / physiology
  • Antigens, CD34
  • Capsid / metabolism
  • Cells, Cultured
  • Gene Expression*
  • Genetic Vectors / genetics*
  • Genetic Vectors / physiology
  • Globins / genetics*
  • Green Fluorescent Proteins / genetics
  • Humans
  • Locus Control Region / genetics*
  • Transduction, Genetic
  • Virus Integration

Substances

  • Antigens, CD34
  • Green Fluorescent Proteins
  • Globins