Comparison of Osteogenesis between Adipose-Derived Mesenchymal Stem Cells and Their Sheets on Poly-ε-Caprolactone/β-Tricalcium Phosphate Composite Scaffolds in Canine Bone Defects

Abstract

Multipotent mesenchymal stem cells (MSCs) and MSC sheets have effective potentials of bone regeneration. Composite polymer/ceramic scaffolds such as poly-ε-caprolactone (PCL)/β-tricalcium phosphate (β-TCP) are widely used to repair large bone defects. The present study investigated the in vitro osteogenic potential of canine adipose-derived MSCs (Ad-MSCs) and Ad-MSC sheets. Composite PCL/β-TCP scaffolds seeded with Ad-MSCs or wrapped with osteogenic Ad-MSC sheets (OCS) were also fabricated and their osteogenic potential was assessed following transplantation into critical-sized bone defects in dogs. The alkaline phosphatase (ALP) activity of osteogenic Ad-MSCs (O-MSCs) and OCS was significantly higher than that of undifferentiated Ad-MSCs (U-MSCs). The ALP, runt-related transcription factor 2, osteopontin, and bone morphogenetic protein 7 mRNA levels were upregulated in O-MSCs and OCS as compared to U-MSCs. In a segmental bone defect, the amount of newly formed bone was greater in PCL/β-TCP/OCS and PCL/β-TCP/O-MSCs/OCS than in the other groups. The OCS exhibit strong osteogenic capacity, and OCS combined with a PCL/β-TCP composite scaffold stimulated new bone formation in a critical-sized bone defect. These results suggest that the PCL/β-TCP/OCS composite has potential clinical applications in bone regeneration and can be used as an alternative treatment modality in bone tissue engineering.

Optimizing Osteogenic Differentiation of Ovine Adipose-Derived Stem Cells by Osteogenic Induction Medium and FGFb, BMP2, or NELL1 In Vitro

“…Recent steps toward optimizing ADSC sheet in canine in vitro were done by Kim et al [ 40 ]. In a new study comparing ADMSC and ADMSC sheets, both groups included scaffolds in critical size defect dog model and showed significantly higher new bone formation after 12 weeks in the ADMSC sheet group [ 41 ]. The cell sheet folding may have limited the analysis of potential osteogenic lineage inducers of oADSCs, but it may propose a solution for controlling cells in future tissue engineering at focal region when implanted in critical size defects or in subcutaneous ectopic mice models.…”

Use of Limiting Dilution Method for Isolation of Nucleus Pulposus Mesenchymal Stem/Progenitor Cells and Effects of Plating Density on Biological Characteristics and Plasticity

“…While stem cells possess therapeutic potential, one of the largest limiting factors is isolating seed cells. Presently, there are several ways to select and purify stem cells in vitro, such as an attachment-based culturing method [ 11 , 12 ], fluorescent-based [ 13 ] or magnetic-based [ 14 , 15 ] cell sorting, or density gradient centrifugation method [ 16 , 17 ]. Among these methods, the best way to isolate NPMSCs remains unclear.…”

Use of stem-cell sheets expressing bone morphogenetic protein-7 in the management of a nonunion radial fracture in a Toy Poodle

“…Bone morphogenetic proteins (BMPs) are growth factors that can be affected by various determinants. BMPs belong to the transforming growth factor β superfamily and are responsible for the cascade of developmental processes in which progenitor cells differentiate into osteoblasts, leading to osteogenesis [ 6 8 12 ]. This unique feature of BMPs has been successfully used in bone repair [ 14 ].…”

“…Previous studies have shown that BMP-modified Ad-MSCs induce vertebral defect regeneration in rodents [ 6 ]. BMP-overexpressing MSCs not only secrete BMPs to promote osteogenesis but also can differentiate into osteogenic cells [ 8 ]. However, transplanted single-cell suspensions do not attach, survive, or proliferate in target tissues [ 11 ].…”

“…Cell sheets are beneficial for cell transplantation because cell–cell junctions and endogenous ECMs are preserved in such sheets [ 1 ]. This ensures homeostasis in the cellular microenvironment, thereby allowing sustained long-term delivery of growth factors and cytokines that promote tissue repair [ 8 11 ]. This case report documents the clinical application of Ad-MSCs overexpressing BMP-7 (BMP-7-MSC) sheets in a fracture site of a dog with a nonunion fracture in the distal radius.…”