title: Dura mater stimulates human adipose-derived stromal cells to undergo bone formation in mouse calvarial defects.
abstract: Human adipose-derived stromal cells (hASCs) have a proven capacity to aid in osseous repair of calvarial defects. However, the bone defect microenvironment necessary for osseous healing is not fully understood. In this study, we postulated that the cell-cell interaction between engrafted ASCs and host dura mater (DM) cells is critical for the healing of calvarial defects. hASCs were engrafted into critical sized calvarial mouse defects. The DM-hASC interaction was manipulated surgically by DM removal or by insertion of a semipermeable or nonpermeable membrane between DM and hASCs. Radiographic, histologic, and gene expression analyses were performed. Next, the hASC-DM interaction is assessed by conditioned media (CM) and coculture assays. Finally, bone morphogenetic protein (BMP) signaling from DM was investigated in vivo using novel BMP-2 and anti-BMP-2/4 slow releasing scaffolds. With intact DM, osseous healing occurs both from host DM and engrafted hASCs. Interference with the DM-hASC interaction dramatically reduced calvarial healing with abrogated BMP-2-Smad-1/5 signaling. Using CM and coculture assays, mouse DM cells stimulated hASC osteogenesis via BMP signaling. Through in vivo manipulation of the BMP-2 pathway, we found that BMP-2 plays an important role in DM stimulation of hASC osteogenesis in the context of calvarial bone healing. BMP-2 supplementation to a defect with disrupted DM allowed for bone formation in a nonhealing defect. DM is an osteogenic cell type that both participates in and stimulates osseous healing in a hASC-engrafted calvarial defect. Furthermore, DM-derived BMP-2 paracrine stimulation appears to play a key role for hASC mediated repair.
authors.affiliation: Hagey Laboratory for Pediatric Regenerative Medicine, Plastic and Reconstructive Surgery Division, Department of Surgery, Stanford University School of Medicine, Stanford, California 94305-5148, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Levi
authors.forename: Emily R
authors.initials: ER
authors.lastname: Nelson
authors.forename: Shuli
authors.initials: S
authors.lastname: Li
authors.forename: Aaron W
authors.initials: AW
authors.lastname: James
authors.forename: Jeong S
authors.initials: JS
authors.lastname: Hyun
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Montoro
authors.forename: Min
authors.initials: M
authors.lastname: Lee
authors.forename: Jason P
authors.initials: JP
authors.lastname: Glotzbach
authors.forename: George W
authors.initials: GW
authors.lastname: Commons
authors.forename: Michael T
authors.initials: MT
authors.lastname: Longaker
mesh_terms: D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D053687:Adult Stem Cells / Q000473:pathology* / Q000637:transplantation; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology / Q000502:physiology; D001861:Bone Regeneration; D002454:Cell Differentiation; D049109:Cell Proliferation; D006259:Craniocerebral Trauma / Q000628:therapy; D004343:Drug Implants; D004388:Dura Mater / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D051379:Mice; D008875:Middle Aged; D012886:Skull / Q000473:pathology*; D017154:Stromal Cells / Q000473:pathology* / Q000637:transplantation; D054457:Tissue Scaffolds; D014183:Transplantation, Heterologous; D014945:Wound Healing
chemical_list: C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; D004343:Drug Implants