An In‐vitro Study on Regeneration of Human Nucleus Pulposus by Using Gelatin/Chondroitin‐6‐Sulfate/Hyaluronan Tri‐copolymer Scaffold

Tissue engineering approaches for treating degenerative intervertebral discs aim to promote tissue regeneration then retard or even reverse the degenerative process. A gelatin/chondroitin-6-sulfate/hyaluronan tri-copolymer was developed to serve as a bioactive scaffold that could help human nucleus pulposus (NP) cells to preserve their cell viability/proliferation and promote matrix synthesis. Each scaffold was seeded with 1 x 10(6) monolayer-expanded human NP cells and then cultured in vitro. Over a 4-week cultivation period, cell-scaffold hybrids demonstrated active cell viability/proliferation and a progressive increase in net production of glycosaminoglycans. In comparison to monolayer cells, scaffold-cultured cells showed significantly higher mRNA expression in collagen II, aggrecan, Sox9, TGFbeta1, and TIMP1. Expression of mRNA was significantly suppressed in collagen I, collagen X, IL1, and Fas-associating death domain protein. Histological studies showed newly synthesized glycosaminoglycans deposits and collagen II in scaffolds. These results indicate that the tri-copolymer scaffold could be considered as a promising bioactive scaffold for regenerating human NP.