title: Serum influence on in-vitro gene delivery using microbubble-assisted ultrasound.
abstract: BACKGROUND
  Plasmid DNA (pDNA) is attractive molecule for gene therapy. pDNA-targeted delivery by efficient and safe methods is required to enhance its intra-tissue bioavailability. Among non-viral methods, sonoporation has become a promising method for in-vitro and in-vivo pDNA delivery. The efficiency of non-viral delivery methods of pDNA is generally limited by the presence of serum.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the influence of serum on in-vitro pDNA delivery using microbubble-assisted ultrasound.
  
  
  METHODS
  The effects of a range of serum concentrations (0-50%) on efficiency of in-vitro pDNA delivery by sonoporation were determined on human glioblastoma cells. Furthermore, the influence of the serum on cell viability, membrane permeabilization, microbubble destruction, and pDNA topology were also assessed.
  
  
  RESULTS
  In-vitro results showed that a low serum concentration (i.e. ≤1%) induced a significant increase in transfection level through an increase in cell viability. However, a high serum concentration (i.e. ≥5%) resulted in a significant decrease in cell transfection, which was not associated with a decrease in membrane permeabilization or loss in cell viability. This decrease in transfection level was in fact positively correlated to changes in pDNA topology.
  
  
  CONCLUSIONS
  Serum influences the efficiency of in-vitro pDNA delivery by sonoporation through change in pDNA topology.
authors.affiliation: UMR Inserm U930, Université François-Rabelais de Tours , Tours , France.
authors.forename: Aya
authors.initials: A
authors.lastname: Zeghimi
authors.forename: Anthony
authors.initials: A
authors.lastname: Novell
authors.forename: Rose-Anne
authors.initials: RA
authors.lastname: Thépault
authors.forename: Patrick
authors.initials: P
authors.lastname: Vourc'h
authors.forename: Ayache
authors.initials: A
authors.lastname: Bouakaz
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Escoffre
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival; D004247:DNA / Q000235:genetics; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005909:Glioblastoma / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D045423:Microbubbles; D009994:Osmolar Concentration; D010539:Permeability; D010957:Plasmids; D014465:Ultrasonics
chemical_list: D004247:DNA
keywords: Gene delivery; microbubble; pDNA topology; serum; sonoporation; ultrasound