Cartilage-scaffold composites produced by bioresorbable β-chitin sponge with cultured rabbit chondrocytes

We newly produced bioresorbable beta-chitin sponge and used it as a scaffold for three-dimensional culture of chondrocytes. beta-Chitin was obtained from the pens of Loligo squid and the beta-chitin sponge was formed into a pillar shape. We produced cartilage-scaffold composites with a cartilage-like layer at the surface by culturing beta-chitin sponge-attached chondrocytes at the surface for 4 weeks. The mean DNA content at week 4 was 2.52-fold more than preculture DNA content. The mean concentration values of chondroitin sulfate and hydroxyproline continued to increase after week 2. Type II collagen and aggrecan genes were both found to be expressed during the experiment. Overall results of the biochemical analysis, along with histochemical and immunohistochemical findings and RT-PCR analysis, indicate that the cartilage-like layer in the chondrocyte-beta-chitin sponge composite was similar to hyaline cartilage. Electron microscopy scanning also revealed that the cell layer at the surface of the beta-chitin sponge was filled with chondrocytes and abundant extracellular matrix. beta-Chitin sponge can be considered biocompatible with chondrocytes, and an adequate scaffold for three-dimensional chondrocyte culture. Because this technique can produce a pillar-shaped composite, we will be able to press-fit the composites into articular cartilage defects without covering the periosteum or suturing the implant.