Regenerative Intervertebral Disc Endplate Based on Biomimetic Three-dimensional Scaffolds

Study Design. Fabrication and characterization of a regenerative intervertebral disc (IVD) cartilaginous endplate (CEP) based on tissue culturing on biomimetic scaffolds. Objective. To fabricate a regenerative CEP to support nutrients and metabolites exchange between IVD and the milieu interior. Summary of Background Data. CEP is the only pathway for most cells inside IVD to obtain nutrients and to eliminate metabolites. However, CEP usually fails at the same time when IVD degenerates. Therefore, reconstruction of CEP becomes an inevitable part of IVD regeneration. In this work, a novel regenerative CEP is fabricated to support nutrients and metabolites exchange of IVD. Methods. Three-dimensional scaffolds were fabricated by cross-linking of hyaluronic acid, chondroitin sulfate, and type II collagen. Then chondrocytes were cultured on the scaffolds. The obtained tissue was then investigated by scanning electron microscope, mechanical tests, and immunohistochemistry tests. In the end, glucose and lactic acid diffusion was carried out to test its nutrients and metabolites exchanging property. Results. Scanning electron microscopy investigations show that the 3-dimensional scaffold has microporous structure. After cell culturing, the inner structure of the obtained product becomes compact. Mechanical tests show that the obtained tissue has strong mechanical property. Immunohistochemistry tests show that the chemical compositions of the fabricated regenerative CEP are the same as its natural counterpart. Moreover, glucose and lactic acid diffuse through the regenerative CEP successfully. Conclusion. The fabricated regenerative CEP shows features similar to its natural counterpart. As the most important function, nutrients and metabolites exchange is verified on it as well. This regenerative CEP may play an important role in overall fabrication of regenerative IVD in near future.