Evaluation of polymer scaffolds to be used in a composite injectable system for intervertebral disc tissue engineering

Adult porcine nucleus pulposus cells were seeded onto gelatin, demineralized bone matrix (DBM), and polylactide scaffolds and cultured in vitro. Cellular behavior in response to the scaffolds was analyzed using biochemical assays, histology, and real-time quantitative reverse transcriptase-polymerase chain reaction. Scanning electron microscopy showed pronounced differences in surface texture of the scaffolds. Nucleus pulposus cells attached and assumed an elongated fibroblast-like morphology on the gelatin and DBM scaffolds. The cells cultured on the gelatin and DBM were metabolically active and expressed types I and 11 collagen and aggrecan. Detached cellular aggregates with a rounded morphology were noted in the culture tubes containing the polylactide scaffolds. Both surface chemistry and texture likely had a role in causing differences in cellular behavior in response to scaffold material. Promising results were observed using the gelatin and dernineralized bone scaffolds, but the behavior of cells cultured on these scaffolds will need to be characterized further. This initial research will be used to direct future work involved in developing this composite injectable tissue engineering system. (c) 2005 Wiley Periodicals, Inc. J Biomed Mater Res 74A: 32-39, 2005.