title: Short-term culture of myeloid leukemic cells allows efficient transduction by adenoviral vectors.
abstract: BACKGROUND
  Ex vivo gene therapy of acute myeloid leukemia (AML) requires efficient transduction of leukemic cells. Recombinant adenovirus has been reported to be a poorly efficient vector in leukemic cells. We investigated leukemic cell culture as a possible method of improving the efficacy of this vector.
  
  
  METHODS
  Leukemic cell lines and primary cultured AML cells were incubated with adenoviral vectors carrying GFP, LacZ, or IL-12 cDNA. Transduction efficiency was evaluated by measuring adenoviral genome copy number and transgene expression in leukemic cells. The expression of the coxsackie/adenovirus receptor (CAR), CD29, CD49e, and CD51/61 was measured, as was the effect of blocking integrin on adenoviral transduction.
  
  
  RESULTS
  Increasing the multiplicity of infection (MOI) to 300 plaque-forming units per cell enhanced transduction of leukemic cell lines and to a lesser degree of AML cells. Analysis of adenoviral genome copy per cell showed only a partial correlation between gene transfer efficiency and transgene expression. Culture of AML cells for 3 days prior to adenoviral transduction increased both adenoviral copy number per cell and the percentage of transgene-expressing cells. CD29, CD49e, and CD51/61 but not CAR expression increased in cultured AML cells between days 0 and 3 and integrin-blocking experiments showed inhibition of transduction in two of four AML samples tested.
  
  
  CONCLUSIONS
  Efficient ex vivo gene transfer in primary cultured AML cells can be achieved by short-term culture of leukemic cells prior to gene transfer with adenoviral vectors at a high MOI. This effect appears to be at least partially mediated by enhanced integrin expression.
authors.affiliation: Unité INSERM 524, Institut de Recherche sur le Cancer de Lille, IFR-114, France.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Vereecque
authors.forename: Aurore
authors.initials: A
authors.lastname: Saudemont
authors.forename: Bruno
authors.initials: B
authors.lastname: Quesnel
mesh_terms: D000208:Acute Disease; D000256:Adenoviridae / Q000235:genetics*; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D005822:Genetic Vectors; D016679:Genome, Viral; D006801:Humans; D007951:Leukemia, Myeloid / Q000235:genetics / Q000473:pathology*; D016133:Polymerase Chain Reaction; D014161:Transduction, Genetic