Effects of Adipose-Derived Stem Cells on Improving the Viability of Diced Cartilage Grafts

Abstract

Diced cartilage grafts are useful for dorsal nasal augmentation; however, long-term resorption usually occurs. The aim of this study was to examine the effects of adipose-derived stem cells on the viability of diced cartilage grafts. Twenty Fischer rats were divided into four groups with diced cartilage grafts wrapped in the following components: abdominal fascia (group I), Surgicel (group II), abdominal fascia plus adipose-derived stem cells (group III), or Surgicel plus adipose-derived stem cells (group IV). Grafts were placed subcutaneously along the dorsal midline, and the weights were recorded both before implantation and after explantation. Histologic examination was performed after 8 weeks using hematoxylin and eosin, safranin O, van Gieson, glial fibrillary acid protein, and von Willebrand factor immunofluorescence staining. The percentage reduction in weight, indicating resorption, was significantly lower in group III (p < 0.01). Both the number of nucleated lacunae per unit area and the proteoglycan content were significantly higher in group III compared with the other groups (p < 0.05). Elastic fibers around the regenerating cartilage islands were seen by van Gieson staining in the fascia groups but not in the Surgicel groups. Glial fibrillary acid protein was also significantly higher in group III (p < 0.01). There was no statistically significant difference in vascular density among the treatment groups (p > 0.05). These findings suggest that adipose-derived stem cells can maintain the viability of diced cartilage, although the exact mechanism remains to be defined. Because adipose-derived stem cells are autologous and easy to harvest, they may be useful for improving the long-term outcomes of diced cartilage grafting.