title: Fetal tissue engineering: in vitro analysis of muscle constructs.
abstract: OBJECTIVE
  This study was aimed at examining the impact of different tissue engineering techniques on fetal muscle construct architecture.
  
  
  METHODS
  Myoblasts from ovine specimens of fetal skeletal muscle were expanded in culture and their growth rates determined. Cells were seeded at different densities onto 3 scaffold types, namely polyglycolic acid (PGA) treated with poly-l-lactic acid (PLLA), a composite of PGA with poly-4-hydroxybutyrate (P4HB), and a collagen hydrogel. Constructs were maintained in a bioreactor and submitted to histologic, scanning electron microscopy, and DNA analyses at different time-points. Statistical analysis was by the likelihood ratio and paired Student's t tests (P <.05).
  
  
  RESULTS
  Fetal myoblasts proliferated at faster rates than expected from neonatal cells. Cell attachment was enhanced in the PGA/PLLA matrix and collagen hydrogel when compared with the PGA/P4HB composite. Necrosis was observed at the center of all constructs, directly proportional to cell seeding density and time in the bioreactor.
  
  
  CONCLUSIONS
  Fetal myoblasts can be expanded rapidly in culture and attach well to PGA/PLLA, as well as collagen hydrogel but less optimally to PGA/P4HB. Excessive cell seeding density and bioreactor time may worsen final construct architecture. These findings should be considered during in vivo trials of muscle replacement by engineered fetal constructs.
authors.affiliation: Harvard Center for Minimally Invasive Surgery, Harvard Medical School, Center for the Integration of Medicine and Innovative Technologies, Massachusetts General Hospital; and Children's Hospital, Boston, MA 02115, USA.
authors.forename: Julie R
authors.initials: JR
authors.lastname: Fuchs
authors.forename: Irina
authors.initials: I
authors.lastname: Pomerantseva
authors.forename: Erin R
authors.initials: ER
authors.lastname: Ochoa
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Vacanti
authors.forename: Dario O
authors.initials: DO
authors.lastname: Fauza
mesh_terms: D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D020100:Hydrogels; D019344:Lactic Acid; D032448:Myoblasts, Skeletal / Q000166:cytology*; D011091:Polyesters; D011100:Polyglycolic Acid; D011108:Polymers; D012756:Sheep; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D020100:Hydrogels; D011091:Polyesters; D011108:Polymers; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide)