Evaluation of various scaffolds for tissue engineered biodisc using annulus fibrosus cells

This study was designed to investigate the effect of hybridization of synthetic/natural materials for annulus fibrosus (AF) tissue regeneration in vitro and in vivo. The synthetic/natural hybrid scaffolds were prepared using PLGA (poly (lactic-co-glycolic) acid), SIS (small intestinal submucosa) and DBP (demineralized bone particles). PLGA, PLGA/SIS(20%), PLGA/DBP(20%) and PLGA/SIS (10%)/DBP(10%) scaffold were manufactured by solvent casting/salt leaching method. Compressive strength was measured. Rabbit AF cells were isolated, cultured and seeded into experimental groups. Hydroxyproline production and DNA quantity of AF cells on each scaffold was measured at 2, 4 and 6 weeks after in vitro culture. Cell-scaffold composites were implanted subcutaneously into athymic mice. After 1, 4 and 6 weeks postoperatively, specimens were taken and H&E, Safranin-O and type I collagen staining were carried out concerning formation of cartilagenous tissue. In vitro PLGA/SIS scaffold was evaluated for total collagen content (hydroxyproline/DNA content) and PLGA scaffold was evaluated for compressive strength.