Gene expression profile of the cartilage tissue spontaneously regenerated in vivo by using a novel double-network gel: comparisons with the normal articular cartilage.

Background: We have recently found a phenomenon that spontaneous regeneration of a hyaline cartilage-like tissue can be induced in a large osteochondral defect by implanting a double-network (DN) hydrogel plug, which was composed of poly-(2-Acrylamido-2-methylpropanesulfonic acid) and poly-(N, N'-Dimetyl acrylamide), at the bottom of the defect. The purpose of this study was to clarify gene expression profile of the regenerated tissue in comparison with that of the normal articular cartilage.

Methods: We created a cylindrical osteochondral defect in the rabbit femoral grooves.