Scaffold attachment region-containing retrovirus vectors improve long-term proviral expression after transplantation of GFP-modified CD34+ baboon repopulating cells

Blood. 2003 Nov 1;102(9):3117-9. doi: 10.1182/blood-2003-03-0962. Epub 2003 Jul 17.

Abstract

Sustained high-level proviral expression is important for clinical applications of gene therapy. Genetic elements including the beta-interferon scaffold attachment region (SAR) have been shown to improve transgene expression in hematopoietic cells. We hypothesized that SAR elements might improve expression and allow the preselection of successfully transduced cells. Thus, we transplanted green fluorescent protein (GFP)-selected cells, half of which had been transduced with either SAR or non-SAR-containing retrovirus vectors, into 3 animals. All animals showed delayed engraftment compared with historic controls (28 vs 15.5 days). GFP marking was seen at levels up to 8% but declined over the first 6 weeks. Importantly, fluorescence intensity was 2- to 9-fold increased in progeny of SAR versus non-SAR vector-modified cells in all hematopoietic lineages for the duration of follow-up (6-12 months). In conclusion, the use of SAR-containing vectors improved transgene expression in hematopoietic repopulating cells, which may obviate the need for multicopy integration to achieve high-level expression and reduce the risk for insertional mutagenesis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Gene Expression
  • Genetic Vectors*
  • Graft Survival
  • Green Fluorescent Proteins
  • Hematopoietic Stem Cell Transplantation*
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / metabolism
  • Kinetics
  • Luminescent Proteins / genetics
  • Matrix Attachment Regions / genetics*
  • Papio
  • Proviruses / genetics
  • Proviruses / growth & development
  • Proviruses / metabolism*
  • Retroviridae / genetics
  • Time Factors
  • Transduction, Genetic / methods*
  • Transduction, Genetic / standards

Substances

  • Luminescent Proteins
  • Green Fluorescent Proteins