earticle

영어

Tissue engineering often requires a well-defined scaffold that is highly porous. The multi-head deposition system (MHDS), a form of solid freeform fabrication, has raised great interest as a method for fabricating scaffolds, since it yields a highly porous inter-connective structure without the use of cytotoxic solvents, and permits the diffusion of nutrients and oxygen. However, fabrication of scaffold using MHDS necessitates thermal procedure that might induce degradation of poly(lactic-co-glycolic acid) (PLGA) followed by accelerating acidification of environment surrounding implantation site. Acidic condition of the extracellular matrix deteriorates an engineered tissue. Moreover, this method is not suitable for introducing proteins, as it includes a heating process. In present study, we sought to determine whether three-dimensional scaffolds fabricated from PLGA with acetyl end group using MHDS method could be appropriately used as a scaffold to regenerate cartilage tissue in vivo. In addition, the surface of a scaffold fabricated using MHDS was coated with a mixture of fibrin and hyaluronic acid (HA) that was used as a vehicle for delivery of both proteins and stem cells. During scaffold fabrication by MHDS method, the acetyl end group modification of PLGA (PLGA-Ac) induced lower decrease of molecular weight than untreated PLGA. After in vivo implantation of the scaffolds with chondrocytes, PLGA-Ac scaffolds showed higher extracellular matrix and GAG content of engineered-cartilage without inflammatory response compared to untreated PLGA scaffolds. Meanwhile, fibrin/HA coating of the scaffold significantly enhanced initial cell attachment. The transplantation of adipose-derived stem cells(ASCs) inoculated on protein-loaded, fibrin/HA-coated scaffolds resulted in more improved tissue formation than did the transplantation of ASCs seeded on uncoated scaffolds or on fibrin/HA-coated scaffolds without proteins, but containing BMP-2 in the cell suspension medium. These results demonstrates that end group modification and physical coating method of scaffolds undergoing thermal process may be useful to enhance in vivo tissue regeneration