Acellular dermal matrix integration in hydrogel scaffolds: A novel approach to cartilage tissue engineering

Scaffold materials impact engineered cartilage properties, but current options like hydrogels and PCL have limitations, including insufficient strength and inflammatory responses. This study explored the efficacy of integrating hydrogel scaffolds with an acellular dermal matrix (ADM) to enhance structural integrity and chondrogenesis.

Human third costal cartilage was obtained and processed to isolate chondrocytes, which were assessed via flow cytometry for surface markers (CD44, CD54, CD31, CD45). Chondrocytes were cultured in a gelatin scaffold with (ADM group) or without ADM sheets (Hydrogel group), then implanted in BALB/c nude mice for 12 weeks. Histological staining and ECM analyses, including GAG and type II collagen ELISA, were conducted on harvested constructs.

The rectangular shape was better preserved in the ADM group compared to the hydrogel group, indicating less contraction and deformation. The scaffold width in the ADM group was significantly greater (9.20±0.23 mm) than that in the hydrogel group (7.40±0.93 mm, p<0.05). Histological analysis revealed an enhanced ECM formation in the ADM group with uniform ECM distribution. The quantitative assays demonstrated significantly higher glycosaminoglycan content (3.3±0.7 μg/mg) and type II collagen levels (11.3±1.6 μg/mg) in the ADM group compared to the hydrogel group (2.2±0.2 μg/mg and 4.6±0.4 μg/mg, respectively; p<0.05).

The ADM-covered hydrogel scaffold effectively maintained its structural integrity and volume in vivo, promoting ECM production compared with the hydrogel-only scaffold. These findings indicate that the ADM-covered hydrogel scaffolds have significant potential for cartilage tissue engineering and reconstructive surgery.