Effect of Collagen and GelMA on Preservation of the Costal Chondrocytes' Phenotype in a Scaffold in vivo.

The aim of the study was to compare type I collagen-based and methacryloyl gelatin-based (GelMA) hydrogels by their ability to form hyaline cartilage in animals after subcutaneous implantation of scaffolds. Materials and Methods: Chondrocytes were isolated from the costal cartilage of newborn rats using 0.15% collagenase solution in DMEM. The cells was characterized by glycosaminoglycan staining with alcian blue. Chondrocyte scaffolds were obtained from 4% type I porcine atelocollagen and 10% GelMA by micromolding and then implanted subcutaneously into the withers of two groups of Wistar rats. Histological and immunohistochemical studies were performed on days 12 and 26 after implantation. Tissue samples were stained with hematoxylin and eosin, alcian blue; type I and type II collagens were identified by the corresponding antibodies. Results: The implanted scaffolds induced a moderate inflammatory response in both groups when implanted in animals. By day 26 after implantation, both collagen and GelMA had almost completely resorbed. Cartilage tissue formation was observed in both animal groups. The newly formed tissue was stained intensively with alcian blue, and the cells were positive for both types of collagen. Cartilage tissue was formed among muscle fibers. Conclusion: The ability of collagen type I and GelMA hydrogels to form hyaline cartilage in animals after subcutaneous implantation of scaffolds was studied. Both collagen and GelMA contributed to formation of hyaline-like cartilage tissue type in animals, but the chondrocyte phenotype is characterized as mixed. Additional detailed studies of possible mechanisms of chondrogenesis under the influence of each of the hydrogels are needed.

[In vitro Cultivation of Functioning Passaged Ciliated Epithelium for Trachea Tissue Engineering].

BACKGROUND: Currently all tissue engineered trachea transplants had no ciliated epithelium until transplantation, and long-term temporary lack of mucociliary clearance leads to patients' condition decline and reduced life quality in postoperative period. So, the need for a better cultivation method and studying ciliated epithelium growth characteristics in cell culture increased rapidly. OBJECTIVE: The aim of our study was to investigate cultivation offunctionally complete passaged ciliated epitheliumfor trachea tissue engineering. METHODS: Human ciliated epithelium isolated from intraoperative bioptate was used for culturing in the special complex medium with morphological and functional characteristics evaluation. RESULTS: Ciliated epithelial cell-groups were obtained by culturing in the special complex medium. Generated cell-groups had ciliary activity and showed well-coordinated movement with functional characteristics similar to native epithelial tissue. The basic parameters of cell-activity were studied. CONCLUSION: Thus our study provides a new insight for the problem of ciliated epithelium in vitro culturing as well as developing the optimal laboratory method.