Novel Simple Strategy for Cartilage Tissue Engineering Using Stem Cells and Synthetic Polymer Scaffold.

Cartilage created by tissue engineering is a promising new development in facial reconstructive surgery. The purpose of this study was to evaluate the histological results of implantation of synthetic polymer scaffold with chondrocytes differentiated from adipose-derived mesenchymal stem cells. Adipose tissue obtained from Wistar albino rats was dissociated, incubated and placed in culture medium. After a sufficient level of stem cell proliferation, the differentiation phase was started. Cells were collected on the 7th and 21st day of culture for chondrogenic characterization. After the 21st day of the differentiation phase of chondrocytes, they were transferred onto poly(dl-lactide-epsilon-caprolactone) synthetic polymer and culture continued for 24 hours. The scaffold with chondrocytes was then implanted into a subcutaneous area of skin on the back of the neck of the rat. Six weeks after implantation, all rats were sacrificed and the implantation areas were analyzed. Chondrocytes derived from adipogenic mesenchymal stem cells were stained positively with collagen II, aggrecan and Sox-9 after the differentiation stages. Histological examination of the excised material showed that chondrocytes were present, and the scaffold had been completely absorbed. The results of this study indicate that the differentiation method from mesenchymal stem cells to chondrogenic lineage was straightforward and scaffold with cells was easily accessible. This technique may be a good option for cartilage tissue engineering.

13-93B3 Bioactive Glass: a New Scaffold for Transplantation of Stem Cell-Derived Chondrocytes.

Research using animal models gives human trials hope for recovery in many fields of regenerative medicine, although they are sometimes poor predictors for human experiences. Our goal was to investigate whether rat chondrocytes, differentiated from adipose-derived stem cells, could be transplanted using a new, easily shaped, bioactive glass scaffold, and to show the immunohistochemical results. Intraperitoneal and retroperitoneal adipose tissue was extracted from 6 male Wistar albino type rats. The fatty tissue samples were fragmented and incubated. Chondrogenic differentiation was carried out and collagen type II, bFGF, and Sox-9 immunohistochemical characterization analysis was performed. Differentiated chondrocytes were implanted on 13-93B3 bioactive glass scaffolds and transplanted into the right ears of the rats. As control, only the biomaterial was transplanted into the left ears of the rats. After 1 month, the rats were sacrificed and transplantation areas were examined immunohistochemically. Histological examination of control samples from the left ears revealed that the biomaterial was covered with connective tissue, its general structure was preserved, and resorption of the scaffold had started. In specimens from the right ears, the biomaterial was covered with connective tissue, its structure was preserved, cartilage cells were present around the biomaterial, and the presence of cartilage tissue was demonstrated immunohistochemically. In conclusion, 13-93B3 bioactive glass scaffold contributed to the formation of new collagen and the survival of chondrocytes, and is a promising new biomaterial that will prove very useful in regenerative medicine.

Effects of Keratinocytes Differentiated from Embryonic and Adipogenic Stem Cells on Wound Healing in a Diabetic Mouse Model.

OBJECTIVE: The current study aims to assess the molecular effects of keratinocytes derived from embryonic and adipose-derived stem cells (ADSCs) on wound healing in mice with diabetes mellitus. MATERIALS AND METHODS: Sixty BALB/c mice were randomly allocated into 6 groups of 10. Following diabetes mellitus induction by intraperitoneal injection of streptozocin, wounds were created and covered with gauze dipped in various solutions: isotonic saline, carrier and transfer medium-engineered dermal template, keratinocytes derived from embryonic stem cells (ESCs), keratinocytes differentiated from ADSCs, or ADSC medium alone. Histopathological changes and immunohistochemical alterations in the activities of cytokeratin 8, cytokeratin 14, epidermal growth factor (EGF), interleukin 8 (IL-8), fibroblast growth factor 2 (FGF-2), monocyte chemoattractant protein 1 (MCP-1), and collagen I were compared among the 6 groups. RESULTS: Histopathological analysis revealed that wound healing was accelerated by application of keratinocytes derived from ESCs. Such cells increased the activities of cytokeratin 8 and cytokeratin 14. No significant among-group differences were noted in terms of IL-8, FGF-2, MCP-1, or collagen I production. CONCLUSIONS: Keratinocytes derived from ESCs accelerated wound healing in mice with diabetes mellitus. The beneficial effects were evident both histomorphologically and immunohistochemically. Although keratinocytes derived from ADSCs are readily available, such cells did not accelerate wound healing.