title: Effect of endothelial cells on bone regeneration using poly(L-lactide-co-1,5-dioxepan-2-one) scaffolds.
abstract: Our recent in vitro study demonstrated that endothelial cells (ECs) might influence the differentiation of bone marrow stromal cells (BMSCs). Therefore, the aim of this study was to describe this effect in vivo, using a rat calvarial bone defect model. BMSCs were isolated from femurs of two-donor Lewis rats and expanded in α-minimum essential medium containing 10% fetal bovine serum. One fifth of BMSCs were induced and differentiated into ECs in an Endothelial Cell Growth Medium-2 and then characterized by a flow cytometry. The remaining BMSCs were cultured in freshly prepared osteogenic stimulatory medium, containing dexamethasone, ascorbic acid and β-glycerophosphate. Either BMSCs alone (BMSC-group) or co-cultured ECs/BMSCs (CO-group) were seeded into poly(L-lactide-co-1,5-dioxepan-2-one) [poly(LLA-co-DXO)] scaffolds, cultured in spinner flasks, and then implanted into symmetrical calvarial defects prepared in recipient rats. The animals were sacrificed after 2 months. The formation of new bone was evaluated by radiography and histology and by the expression of osteogenic markers using reverse transcriptase-polymerized chain reaction (RT-PCR). To investigate vessel formation, histological staining was performed with EC's markers. The radiographical and histological results showed more rapid bone formation in the CO- than in the BMSC-group. However, the expression of EC's marker was similar on both groups by histological analysis after 2 months postoperatively. Furthermore, the CO-group exhibited greater expression of osteogenic markers as demonstrated by RT-PCR. The results are consistent with the previous in vitro findings that poly(LLA-co-DXO) scaffold might be suitable candidate for bone tissue engineering. In vivo, bone regeneration was enhanced by a construct of the polymer scaffold loaded with co-cultured cells.
authors.affiliation: Department of Clinical Dentistry, Center for Clinical Dental Research, University of Bergen, Norway.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Xing
authors.forename: Ying
authors.initials: Y
authors.lastname: Xue
authors.forename: Staffan
authors.initials: S
authors.lastname: Dånmark
authors.forename: Kerstin
authors.initials: K
authors.lastname: Schander
authors.forename: Siren
authors.initials: S
authors.lastname: Ostvold
authors.forename: Kristina
authors.initials: K
authors.lastname: Arvidson
authors.forename: Sølve
authors.initials: S
authors.lastname: Hellem
authors.forename: Anna
authors.initials: A
authors.lastname: Finne-Wistrand
authors.forename: Ann-Christine
authors.initials: AC
authors.lastname: Albertsson
authors.forename: Kamal
authors.initials: K
authors.lastname: Mustafa
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D001861:Bone Regeneration / Q000187:drug effects* / Q000235:genetics; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006571:Heterocyclic Compounds / Q000494:pharmacology*; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D011091:Polyesters / Q000494:pharmacology*; D019919:Prosthesis Implantation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011859:Radiography; D051381:Rats; D011917:Rats, Inbred Lew; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D006571:Heterocyclic Compounds; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D011091:Polyesters; D012333:RNA, Messenger; C556909:poly(L-lactide)-co-(1,5-dioxepan-2-one); C091881:1,5-dioxepan-2-one