Konjac glucomannan‐based hydrogel with hyaluronic acid as a candidate for a novel scaffold for chondrocyte culture

Chondrocytes were cultured using konjac glucomannan (KGM) and hyaluronic acid (HA) as a scaffold for cartilage regeneration. They were subsequently compared with scaffolds produced using agarose hydrogels. Chondrocytes derived from Japanese white rabbits were cultured: 2.0 × 10 5 cells were seeded on KGM containing hyaluronic acid (KGM/HA) and agarose and cultured for 5 days. Their viability was assayed using WST‐8 procedures; the ultimate stress and modulus of elasticity of each construct was calculated. After 3 days of cultivation, mRNA in chondrocytes, such as collagen types I and II and aggrecan, were measured using RT‐PCR. Both chondrocyte‐seeded constructs were stained with safranin O/fast green and were evaluated histologically. Chondrocyte viability decreased concomitantly with increasing KGM/HA or agarose concentration and with culture time. Cell viability in 2% agarose was significantly lower than that in 2% KGM/HA on the third and fifth days ( p < 0.05). The primary elastic modulus increased concomitantly with increasing polysaccharide concentration. Elastic moduli of 2% KGM/HA with chondrocytes (0.389 ± 0.119 N/mm 2 ) showed little difference from those without chondrocytes (0.283 ± 0.243 N/mm 2 ), although those of 2% agarose with chondrocytes (0.403 ± 0.094 N/mm 2 ) were significantly lower than those without chondrocytes (0.736 ± 0.227 N/mm 2 ; p < 0.05). Collagen type II mRNA expression was higher in KGM/HA and agarose than in monolayer cultures, although KGM/HA had lower aggrecan mRNA expression levels than did agarose. Histological tests of KGM/HA–chondrocyte constructs revealed chondrocyte aggregation and proteoglycan production in the pericellular region. The results show that KGM/HA might be useful for chondrocyte culture. Copyright © 2009 John Wiley & Sons, Ltd.