title: In vivo bone formation by human marrow stromal cells in biodegradable scaffolds that release dexamethasone and ascorbate-2-phosphate.
abstract: An unsolved problem with stem cell-based engineering of bone tissue is how to provide a microenvironment that promotes the osteogenic differentiation of multipotent stem cells. Previously, we fabricated porous poly(D,L-lactide-co-glycolide) (PLGA) scaffolds that released biologically active dexamethasone (Dex) and ascorbate-2-phosphate (AsP), and that acted as osteogenic scaffolds. To determine whether these osteogenic scaffolds can be used for bone formation in vivo, we seeded multipotent human marrow stromal cells (hMSCs) onto the scaffolds and implanted them subcutaneously into athymic mice. Higher alkaline phosphatase expression was observed in hMSCs in the osteogenic scaffolds compared with that of hMSCs in control scaffolds. Furthermore, there was more calcium deposition and stronger von Kossa staining in the osteogenic scaffolds, which suggested that there was enhanced mineralized bone formation. We failed to detect cartilage in the osteogenic scaffolds (negative Safranin O staining), which implied that there was intramembranous ossification. This is the first study to demonstrate the successful formation of mineralized bone tissue in vivo by hMSCs in PLGA scaffolds that release Dex and AsP.
authors.affiliation: Department of Biomedical Sciences, National Institute of Health, 5 Nokbun-dong, Eunpyung-gu, Seoul 122-701, Republic of Korea.
authors.forename: Hyongbum
authors.initials: H
authors.lastname: Kim
authors.forename: Hwal
authors.initials: H
authors.lastname: Suh
authors.forename: Sangmee Ahn
authors.initials: SA
authors.lastname: Jo
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Kim
authors.forename: Jung Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Eun Hae
authors.initials: EH
authors.lastname: Kim
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Reinwald
authors.forename: Sang-Hyug
authors.initials: SH
authors.lastname: Park
authors.forename: Byoung-Hyun
authors.initials: BH
authors.lastname: Min
authors.forename: Inho
authors.initials: I
authors.lastname: Jo
mesh_terms: D000469:Alkaline Phosphatase / Q000096:biosynthesis; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D001672:Biocompatible Materials / Q000008:administration & dosage* / Q000737:chemistry*; D001846:Bone Development; D001854:Bone Marrow Cells / Q000166:cytology; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002356:Cartilage / Q000378:metabolism; D002478:Cells, Cultured; D004396:Coloring Agents / Q000494:pharmacology; D003907:Dexamethasone / Q000008:administration & dosage*; D048091:Guided Tissue Regeneration / Q000379:methods*; D006801:Humans; D017403:In Situ Hybridization; D019344:Lactic Acid / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D010012:Osteogenesis; D010619:Phenazines / Q000494:pharmacology; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry; D017154:Stromal Cells / Q000166:cytology*; D013997:Time Factors; D023822:Tissue Engineering; D015854:Up-Regulation
chemical_list: D000893:Anti-Inflammatory Agents; D001672:Biocompatible Materials; D004396:Coloring Agents; D010619:Phenazines; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; C011669:ascorbate-2-phosphate; D011100:Polyglycolic Acid; D019344:Lactic Acid; D003907:Dexamethasone; D000469:Alkaline Phosphatase; D001205:Ascorbic Acid; D002118:Calcium; C009195:safranine T