title: Gene delivery in a mouse xenograft of a retargeted retrovirus to a solid 143B osteosarcoma.
abstract: BACKGROUND
  Osteosarcomas are the most common primary bone malignancies found in children and adolescents. An optimized system was developed for efficient retroviral gene delivery into solid 143B osteosarcoma tumors in mice using a retargeted Env. In these studies, the viral Env CP was isolated from an in vitro screen of a library of feline leukemia virus Env randomized in the receptor-binding domain and maintained high titer on human 143B osteosarcoma cell line.
  
  
  RESULTS
  The vector developed to express the random Env libraries encoded the drug selectable marker neo. To adapt this for studies in live animals, the murine based vector was modified to express the luciferase gene. The bicistronic vector developed expressed both the CP Env and luciferase in the presence of either the MPMV CTE or a WPRE element. Virus bearing the CP FeLV Env variant maintained high titers after concentration allowing for direct visualization of delivery of the luciferase gene in subcutaneous 143B osteosarcoma tumors.
  
  
  CONCLUSIONS
  This system serves as a proof-of-concept for the use of novel FeLV Env pseudotyped MLV particles for in vivo gene delivery. Gene delivery and expression of lucerifase from viral particles bearing the CP Env was readily detected in live mice after a single round of intratumor injection.
authors.affiliation: Department of Biochemistry, University of Medicine and Dentistry of New Jersey–Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.forename: Anindita
authors.initials: A
authors.lastname: Sarangi
authors.forename: Dai-Tze
authors.initials: DT
authors.lastname: Wu
authors.forename: Jaya
authors.initials: J
authors.lastname: Kanduri
authors.forename: Monica J
authors.initials: MJ
authors.lastname: Roth
mesh_terms: D000293:Adolescent; D000818:Animals; D002648:Child; D004195:Disease Models, Animal; D018014:Gene Transfer Techniques; D017930:Genes, Reporter; D015316:Genetic Therapy / Q000379:methods*; D064593:Heterografts; D006801:Humans; D005256:Leukemia Virus, Feline / Q000235:genetics*; D008156:Luciferases / Q000032:analysis; D051379:Mice; D012516:Osteosarcoma / Q000628:therapy*; D013194:Staining and Labeling
chemical_list: D008156:Luciferases