BACKGROUND/ PURPOSE: 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.
BACKGROUND/ PURPOSE: 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: Elizabeth F Maughan; Robert E Hynds; Toby J Proctor; Sam M Janes; Martin Elliott; Martin A Birchall; Mark W Lowdell; Paolo De Coppi Journal: Curr Stem Cell Rep Date: 2017-10-26