title: Quantification of VP22-GFP spread by direct fluorescence in 15 commonly used cell lines.
abstract: BACKGROUND
  The intercellular transport property of VP22 chimeric proteins offers the opportunity for the improvement of gene therapy delivery systems. Since enhanced therapeutic effects of transduced genes already have been exemplified for chimeric proteins VP22-p53 and VP22-tk, we were interested in examining whether spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species.
  
  
  METHODS
  To study intercellular spread of VP22-GFP fusion proteins, 15 different mammalian cell lines were transfected with 200-2000 ng of VP22-GFP or GFP expression plasmids. Expression of VP22-GFP or GFP was monitored by fluorescence microscopy of live GFP fluorescence and direct FACS analysis. For selected cell lines, antibody detection of VP22-GFP spread was analysed by confocal microscopy as a control.
  
  
  RESULTS
  Spread of VP22-GFP fusion proteins was detected in all 15 cell lines tested, and quantified by FACS analysis. Experimental conditions were found to be critical in the investigation of VP22-mediated intercellular spread.
  
  
  CONCLUSIONS
  Results of our study indicate that spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species. Therefore, further evidence is provided that VP22-enhanced gene therapeutic effects may be obtained irrespective of the target organ/tissue to be addressed.
authors.affiliation: Medical University Clinic Tübingen, Germany. wolfgang.wybranietz@uni-tuebingen.de
authors.forename: W A
authors.initials: WA
authors.lastname: Wybranietz
authors.forename: F
authors.initials: F
authors.lastname: Prinz
authors.forename: M
authors.initials: M
authors.lastname: Spiegel
authors.forename: A
authors.initials: A
authors.lastname: Schenk
authors.forename: M
authors.initials: M
authors.lastname: Bitzer
authors.forename: M
authors.initials: M
authors.lastname: Gregor
authors.forename: U M
authors.initials: UM
authors.lastname: Lauer
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D002415:Cats; D002460:Cell Line; D006224:Cricetinae; D004285:Dogs; D015316:Genetic Therapy; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D014018:Tissue Distribution; D014162:Transfection; D015678:Viral Structural Proteins / Q000235:genetics* / Q000378:metabolism*
chemical_list: D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D015678:Viral Structural Proteins; C073413:herpes simplex virus type 1 protein VP22; D049452:Green Fluorescent Proteins