Adipose-Derived Stem Cells Combined with a Demineralized Cancellous Bone Substrate for Bone Regeneration

Abstract

Mesenchymal stem cells (MSCs) isolated from cadaveric adipose tissue can be obtained in large quantities, and have been reported in the literature to be capable of inducing bone formation in vivo and ex vivo.( 1-6 ) The hypothesis tested whether a demineralized cancellous bone matrix (DCBM) can provide an effective substrate for selection and retention of stem cells derived from the stromal vascular fraction (SVF) of adipose. Human cadaveric adipose tissue was recovered from a donor and digested. The resulting SVF-containing MSCs were seeded onto the demineralized bone allografts, after which the nonadherent cells were washed off. The MSCs were characterized using a flow cytometer and tri-lineage differentiation (osteogenesis, chondrogenesis, and adipogenesis) in vitro. The stem cell-seeded allografts were also characterized for cell number, adherence to the DCBM, osteogenic activity (alkaline phosphatase and Alizarin Red staining), and bone morphorgenic protein (BMP) quantity. Flow cytometry identified a mean total of 7.2% MSCs in SVF and 87.2% MSCs after culture. The stem cells showed the capability of differentiating into bone, cartilage, and fat. On the 21 stem cell-seeded bone allografts, there were consistent, attached, viable cells (100,744±22,762 cells/cube). An assessment of donor age, gender, and body mass index revealed no significant differences in cell numbers. Enzyme-linked immunosorbent assay revealed the presence of BMP-2 and BMP-7. In conclusion, this bone graft contains three key elements for bone regeneration: adhered osteogenic stem cells, 3D osteoconductive bone scaffold, and osteoinductive BMP signal. It therefore has the potential to be effective for bone regeneration.

Copaiba oil effect on experimental jaw defect in Wistar rats

“…The two grafting materials seemed to perform in a similar way concerning their contribution to bone formation which is consistent whit other studies 1,2,4,5,20 . They appeared to be osteoconductive, leading to a mineralized bone matrix with osteoblasts and chronic inflammatory infiltrate.…”

Adipose-Derived Stem Cells in Tissue Regeneration: A Review

“…ASC-derived osteogenic precursors from both murine and rat adipose tissues, together with other animals such as rabbits, dogs, horses, rhesus monkey, and even brown bear, have also been described [63][64][65][66][67][68]. Most recently, the isolation of ASCs from human cadaveric adipose tissue and their adherence and survival on demineralized bone allografts has been reported [69], suggesting that viable ASCs for osteogenic differentiation may also be obtained from cadavers within 24 hours of their death. Using in vitro culture systems, the expression patterns of key osteogenic genes have been assessed using livecell, temporal gene expression analysis of ASC osteogenesis under dexamethasone/VD3 induction [70], and numerous studies characterize the role of key signaling pathways in this lineage [71][72][73][74][75][76][77][78].…”

Development of an improved bone washing and demineralisation process to produce large demineralised human cancellous bone sponges

“…Different sizes of mineralised bone cube required different times of demineralisation, in this report 24 h was found to demineralise all 3.4 cm 3 sponges and 48 h was found to demineralise all 8.0 cm 3 sponges. Most studies on demineralised bone have reported on ground cortical bone as the starting material and several reports have suggested that cancellous bone contains low levels of BMPs and as such are mostly osteoconductive (Mauney et al 2005), although a Cell Tissue Bank recent study indicated that cancellous bone contains similar levels of BMP2, BMP4 and BMP7 to those found in cortical bone (Shi et al 2012). In addition, the nature of the porous bony trabeculae could provide a suitable microenvironment for osteoblastic cell attachment and differentiation, again previously reported (Shi et al 2012;Smith et al 2014).…”

“…Most studies on demineralised bone have reported on ground cortical bone as the starting material and several reports have suggested that cancellous bone contains low levels of BMPs and as such are mostly osteoconductive (Mauney et al 2005), although a Cell Tissue Bank recent study indicated that cancellous bone contains similar levels of BMP2, BMP4 and BMP7 to those found in cortical bone (Shi et al 2012). In addition, the nature of the porous bony trabeculae could provide a suitable microenvironment for osteoblastic cell attachment and differentiation, again previously reported (Shi et al 2012;Smith et al 2014). We have not investigated the osteoinductive potential of these larger DBM sponges, however, we have previously demonstrated that 1.0 cm 3 cancellous DBM sponges, produced using similar methodology as described here, are osteoinductive when implanted into a rodent model .…”

“…In this report, demineralisation proceeds under closed conditions and each of the reagents and equipment used in this study are Good Manufacturing Practice (GMP) compliant and are currently used safely in GMP processing of tissue. DBM sponges could be used in combination with mesenchymal stem cells (Shi et al 2012;Liu et al 2008) or could be used in combination with DBM pastes or putties. If required, the graft material could also be enhanced with the addition of recombinant human BMPs (rhBMP), such as rhBMP-2 (Elsalanty et al 2008;Burkus et al 2002).…”