title: Fetal tracheal augmentation with cartilage engineered from bone marrow-derived mesenchymal progenitor cells.
abstract: OBJECTIVE
  The authors have described previously the use of engineered fetal cartilage in a large animal model of fetal tracheal repair. This study was aimed at comparing cartilage engineered from bone marrow-derived stromal cells (BMSC) to native and engineered cartilage, in this model.
  
  
  METHODS
  Ovine BMSC were expanded in vitro, seeded onto biodegradable scaffolds, and maintained in transforming growth factor beta 1 (TGF-beta1)-supplemented medium for 3 months (group I). Identical scaffolds were seeded with fetal chondrocytes (group II). All constructs were analyzed in vitro, implanted into fetal tracheas, and harvested after birth for further analysis.
  
  
  RESULTS
  There were no differences in survival between the groups. All BMSC-based constructs exhibited chondrogenic differentiation. Matrix analyses in vitro showed that both groups had similar levels of glycosaminoglycans (GAG) and type II collagen (C-II), but lower levels of elastin when compared with native fetal cartilage. Yet, compared with group II, group I had higher levels of GAG, equal levels of C-II, and lower levels of elastin. However, remodeling resulted in no differences between the 2 groups in any of these variables in vivo.
  
  
  CONCLUSIONS
  The bone marrow may be a useful cell source for cartilage engineering aimed at the surgical repair of severe congenital tracheal anomalies, such as tracheal atresia and agenesis, in utero.
authors.affiliation: Harvard Center for Minimally Invasive Surgery, Center for the Integration of Medicine and Innovative Technologies, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Julie R
authors.initials: JR
authors.lastname: Fuchs
authors.forename: Didier
authors.initials: D
authors.lastname: Hannouche
authors.forename: Shinichi
authors.initials: S
authors.lastname: Terada
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Vacanti
authors.forename: Dario O
authors.initials: DO
authors.lastname: Fauza
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001853:Bone Marrow / Q000378:metabolism*; D002356:Cartilage / Q000601:surgery / Q000637:transplantation*; D002454:Cell Differentiation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000378:metabolism / Q000637:transplantation; D005260:Female; D005333:Fetus / Q000601:surgery*; D008648:Mesoderm / Q000378:metabolism*; D039902:Multipotent Stem Cells / Q000637:transplantation*; D019651:Plastic Surgery Procedures / Q000379:methods; D017154:Stromal Cells / Q000378:metabolism; D023822:Tissue Engineering / Q000379:methods*; D014132:Trachea / Q000196:embryology / Q000601:surgery*; D014140:Tracheotomy / Q000379:methods