In Vivo Evaluation of Mixtures of Uncultured Freshly Isolated Adipose-Derived Stem Cells and Demineralized Bone Matrix for Bone Regeneration in a Rat Critically Sized Calvarial Defect Model

Abstract

Although many studies have suggested that human adipose tissue contains pluripotent stem cells, a few reports are available on stromal vascular fraction (SVF). In the present study, we evaluated the bone formation capacities of SVF. We implanted uncultured freshly isolated adipose-derived stem cells combined with demineralized bone matrix (DBM) to induce bone regeneration in a critically sized rat calvarial defect model. We used DBM (DBX(®)) and/or poly(70L-lactide-co-30DL-lactide) copolymer PLA as a scaffold. Fifty white rats were randomized to 5 different groups (n=10): (1) control, (2) DBM, (3) DBM + SVF, (4) DBM + PLA, and (5) DBM + PLA + SVF groups. After acquiring SVF, an 8-mm critically sized calvarial defect was made in each rat. Specimens were harvested at 8 weeks postimplantation and evaluated radiographically and histologically. New bone formation was qualified by hematoxylin and eosin staining and anti-osteocalcin antibody (OC4-30) immunostaining of calvarial sections. Amounts of mineralization were determined by radiodensitometric analysis. In gross appearance, the DBM + SVF and DBM + PLA + SVF groups showed more abundant bone formation than the other groups. Radiodensitometric evaluations revealed that significant intergroup differences were observed according to the Kruskal-Wallis (rank) test (P=0.030<0.05). The 5 groups show different amounts of filling of bone defects (control: 13.48%; DBM: 39.94%; DBM + SVF: 57.69%; DBM + PLA: 24.86%; DBM + PLA + SVF: 42.75%). Histological evaluation revealed that there was abundant new bone formation in the DBM + SVF and DBM + PLA + SVF groups. It was found that undifferentiated adipose-derived stem cells in the form of SVF induced new bone formation in rat calvarial defects. Accordingly, SVF offers a practical, promising candidate for regenerative tissue engineering or cell-based therapy.

Bone Regeneration by Demineralized Dentin Matrix in Skull Defects of Rats

“…Stem cells from readily available sources, including discarded adipose tissue, have the propensity to differentiate into bone. Recent studies examine a multi-component technique consisting of a novel side population of adipose stem cells cultured on demineralized bone and dentin matrix, for tissue engineering applications [8][9][10] . In the present study, we investigated the extent to which DDM induces bone repair by implanting DDM derived from bovine teeth grafted in rat skull defects.The new bone formed from the defect margin in the control group, but in the graft group, new bone formation occurred from individual DDM granules within the defect, and not just from the margin.…”

“…We have demonstrated that demineralized dentin matrix (DDM) acts as a scaffold for repair of articular cartilage defects 7) . Moreover, recent studies examine a multi-component technique consisting of a novel side population of multi-purpose stem cells cultured on demineralized bone and dentin matrix, for tissue engineering applications [8][9][10][11][12][13] . The dentin of extracted teeth used as an autogenous bone substitute would be safe for grafting.…”

Signals Between Cells and Matrix Mediate Bone Regeneration

“…Other sources for bone forming cells could be the umbilical cord, peripheral blood, adipose tissue, dental pulp or periodontium (Goodwin et al 2001;Honda et al 2011;Rhee et al 2010;Yamamoto et al 2007). Human embryonic stem (hES) cells also being considered as an option due to their fast growth and the fact that these cells, if kept as undifferentiated cell lines, are pluripotential and capable of differentiating to many tissue types under the right conditions (Bahadur et al 2011;Lerou &Daley 2005).…”

Stem Cell Research: A New Era for Reconstructive Surgery

“…Some studies have suggested that the osteogenic potential is similar between BMMSCs and ADSCs, however, ADSCs might be a better alternative due to the lack of morbidity at the donor site. [17] Other studies also claimed that the avoidance of in vitro expansion might make SVF more suitable for clinical application. [15,17] Besides, various scaffolds, both biological and synthetic, have also been studied in this field.…”

“…[17] Other studies also claimed that the avoidance of in vitro expansion might make SVF more suitable for clinical application. [15,17] Besides, various scaffolds, both biological and synthetic, have also been studied in this field. Bruder et al used porous ceramic cylinders consisting of hydroxyapatite (65 per cent) and beta-tricalcium phosphate ceramic (35 per cent) with BM-MSCs for bone regeneration.…”