title: Recombinant vascular endothelial growth factor secreted from tissue-engineered bioartificial muscles promotes localized angiogenesis.
abstract: BACKGROUND
  Therapeutic angiogenesis by the administration of recombinant vascular endothelial growth factor (rVEGF) is a novel strategy for the treatment of ischemic disorders. rVEGF has been delivered as a protein, by plasmid DNA, and by genetically engineered cells with different pharmacokinetic and physiological properties. In the present study, we examined a new method for delivery of rVEGF using implantable bioartificial muscle (BAM) tissues made from genetically modified primary skeletal myoblasts. Our goal was to determine whether the rVEGF delivered by this technique promoted controlled angiogenesis in nonischemic and/or ischemic adult mouse tissue.
  
  
  RESULTS
  Primary adult mouse myoblasts were retrovirally transduced to secrete human or mouse rVEGF and tissue-engineered into implantable 1x10 to 15-mm BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted 290 to 511 ng of bioactive mouse or human VEGF/BAM per day. rVEGF BAMs implanted subcutaneously into syngeneic mice caused a 30-fold increase in the number of CD31-positive capillary cells within the BAM by 1 week compared with control BAMs. Implantation of rVEGF-secreting BAMs into ischemic hindlimbs resulted in a 2- to 3-fold increase in capillary density of neighboring host muscle by 1 week and out to 4 weeks with no evidence of hemangioma formation.
  
  
  CONCLUSIONS
  Local delivery of rVEGF from BAMs rapidly increases capillary density both within the BAM itself and in adjacent ischemic muscle tissue. Genetically engineered muscle tissue provides a method for therapeutic protein delivery in a dose-regulated fashion.
authors.affiliation: Department of Pathology, Brown University School of Medicine, and The Miriam Hospital, Providence, RI, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
authors.forename: J
authors.initials: J
authors.lastname: Shansky
authors.forename: M
authors.initials: M
authors.lastname: Del Tatto
authors.forename: P
authors.initials: P
authors.lastname: Ferland
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: H
authors.initials: H
authors.lastname: Vandenburgh
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D016228:Endothelial Growth Factors / Q000008:administration & dosage* / Q000235:genetics / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018014:Gene Transfer Techniques; D006085:Graft Survival / Q000187:drug effects / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007511:Ischemia; D008222:Lymphokines / Q000008:administration & dosage* / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D018482:Muscle, Skeletal / Q000098:blood supply / Q000378:metabolism* / Q000637:transplantation; D018919:Neovascularization, Physiologic / Q000187:drug effects* / Q000235:genetics; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000378:metabolism; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: D016228:Endothelial Growth Factors; D008222:Lymphokines; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors