Chondrogenesis of chondrocyte cell sheets / 中国组织工程研究

ABSTRACT

BACKGROUND:The cell-sheet technology, based on a temperature-responsive culture, has been drawing more and more attention;however, the temperature-responsive culture dish is quite expensive. Therefore, it is imperative to develop a substitutive technique.OBJECTIVE: To study the feasibility of cell-sheet ulturing using common culture dish, and investigate the chondrogenesis of the cell sheet. METHODS: A piece of nasal septal cartilage was adopted from a patient with deviation of nasal septum to extract primary chondrocytes that were then cultured and amplified. The passage 3 chondrocytes were used to construct ell sheets. Monolayer cell sheet was formed by intensive culturing and allowing the extracellular matrix secretion. Bilayer cell sheet was constructed by seeding passage 2 chondrocytes on the monolayer cell sheet. The cell sheets were harvested using cell scraper, their properties were investigated prior to plantation into nude mice to construct the tissue-engineered cartilage. RESULTS AND CONCLUSION: Both bilayer and monolayer cell sheets with soft tremellose structures showed no significant difference through naked eyes. The newly harvested cell sheets appeared to have good fluidity and gelation. Eight weeks after mplantation into the nude mice, mature cartilage blocks were obtained. Histologically, the cell sheets were thin films composed by layered chondrocytes and extracellular matrix. Glycosaminoglycan formation and type Ⅱ collagen expressions were observed in the cell sheets cultured in vitro. The explanted samples exhibited ature cartilaginous tissue at 8 weeks after implantation. Biochemical analysis showed that the DNA contents of the neocartilages were higher than those of native human costal cartilage, while the contents of glycosaminoglycan and hydroxyproline were similar to native human nasal septal cartilage. To conclude, the hondrocyte cell sheets are likely to be constructed and harvested successfully using common culture dish, and the cell sheets exhibit favourable chondrogenesis.