Growth of Bone Marrow Derived Osteoblast-Like Cells into Coral Implant Scaffold: Preliminary Study on Malaysian Coral

Problem statement: Biomaterial fabrication in Malaysia started as a consequence of the demand for cheaper implant materials. Various biomaterials have been developed utilizing local resources like Malaysian coral. Locally processed Malaysian coral need to be complemented with proper evaluation and testing including toxicology, biocompatibility, mechanical properties, physicochemical characterization and in vivo testing. The present study was carried out to assess natural coral of porites species as scaffold combined with in vitro expanded Bone Marrow Derived Osteoblast-Like cells (BM-DOL), in order to develop a tissue-engineered bone graft in a rat model. Approach: Coral was used in a block shape with a dimension of 10 mm length × 5 mm width × 5 mm thickness. BM-DOL cells were seeded into porous coral scaffold in a density of 5×106 mL^-1. After 7 days of in vitro incubation in osteogenic medium, one block was processed for light (LM) and Scanning Electron Microscopy (SEM) observations while the other blocks were implanted subcutaneously in the back of 5 weeks-old Sprague-Dawely rats for 3 months. Coral blocks without cells were implanted as a control. The implants harvested and processed for gross inspection, histological and scanning electron microscopy observations. Results: Both LM and SEM showed attachment of well arrangement multilayer cells inside the pores of in vitro seeded coral scaffolds. Gross inspection of all in vivo coral-cell complexes implants revealed vascularized like bone tissue formation. Histological sections revealed mature bone formation occurred in the manner resemble intramembraneous bone formation. SEM observations revealed multi-layer cellular proliferation with abundant collagen covered the surface of coral implants. Control group showed resorbed coral block. Conclusion: This study demonstrated that Malaysian coral can be use as a suitable scaffold material for delivering bone marrow mesenchymal stem cells in tissue engineering and therefore, offers a great potential to enhance bone healing around implants in a compromised bone bed.