title: Osteoblasts cultured on three-dimensional synthetic hydroxyapatite implanted on a chick allantochorial membrane induce ectopic bone marrow differentiation.
abstract: Osteoblast (OB) activities have been studied on hydroxyapatite three-dimensional (3D) scaffolds in comparison with traditional planar substrata. OBs cultured on 3D displayed increased proliferation, differentiation, and matrix protein synthesis, when compared to 2D cultures on the same substrata. Confluent cultures, however, could not be maintained for long, due to insufficient fluid diffusion within 3D scaffolds that impaired cell viability. Thus, confluent OB 3D cultures were implanted on the allantochorial membrane of chick embryos. Vessels from the embryo colonized the bone-like network giving rise in the presence of OBs to an ectopic bone marrow formation in the intratrabecular spaces. In the absence of OBs, when the biomaterial alone was implanted, blood vessels were still present but hematopoietic marrow was absent. In both cases osteoclasts (OCs) derived from the host were found on the implant surface. These results indicated that scaffolds with cells can be easily vascularized and confirmed the role of OBs in the definition of the microenvironment that induce blood marrow differentiation in the intratrabecular spaces.
authors.affiliation: Department of Human Anatomy and Histology, School of Medicine, University of Bari, Bari, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Mancini
authors.forename: Roberto
authors.initials: R
authors.lastname: Tamma
authors.forename: Maria
authors.initials: M
authors.lastname: Settanni
authors.forename: Claudia
authors.initials: C
authors.lastname: Camerino
authors.forename: Nicola
authors.initials: N
authors.lastname: Patano
authors.forename: Giovanni
authors.initials: G
authors.lastname: Greco
authors.forename: Maurizio
authors.initials: M
authors.lastname: Strippoli
authors.forename: Alberta
authors.initials: A
authors.lastname: Zallone
mesh_terms: D000481:Allantoin; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology*; D002454:Cell Differentiation; D002642:Chick Embryo; D002823:Chorion / Q000166:cytology*; D017886:Durapatite; D006801:Humans; D010006:Osteoblasts / Q000166:cytology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000481:Allantoin; D017886:Durapatite