Objective To assess the feasibility of using biodegradable poly (lactic-co-glycolic acid) (PLGA) scaffold with controlled release of rhBMP-2 and its effect on the osteogenic activity of MSCs in vitro. Methods The PLGA scaffolds with rhBMP-2 sustained release system were made by combination of porogen-leaching and freeze-drying. The drug release kinetics was measured by enzyme-linked immunosorbent assay (ELISA) in vitro. MSCs were isolated from the bone marrow of human and cultured for 3 passages. Then, MSCs were seeded onto PLGA scaffolds. PLGA scaffolds without rhBMP-2 were used as experimental controls . Scanning electron microscopy(SEM) was used to observe the morphology of MSCs. The cell proliferation was determined by MTT assay. Results The rhBMP-2 was encapsulated into PLGA scaffolds and it was found to be continuously released from the scaffolds. The scaffolds have evident enhancing effect on ectopia osteogenesis. Conclusion PLGA scaffold containing rhBMP-2 is a new promising tissue engineering scaffold.

BACKGROUND: Acellular vascular matrix as vascular scaffold has following advantages: acellular vascular matrix possesses complicated three-dimensional structure of natural blood vessels. Growth factor and structural domain on the surface of acellular matrix helps for cell adhesion and infiltration.OBJECTIVE: To prepare acellular vascular matrix material and to evaluate its biocompatibility in vivo and in vitro.METHODS: Trypsin and Triton X-100 were used to gradually dispose pig carotid artery and to prepare acellular vascular matrix. The biocompstibility of the material was evaluated by implantation in muscle, acute toxicity experiment and cytotoxicity test in vitro.RESULTS AND CONCLUSION: The acallular vascular matrix material possessed good chemical stability and did not release harmful factors that produced destruction and dissolution in erythrocytes, without acute hemolytic reaction or toxic effects on cell growth. The acellular vascular matrix material showed lots of inflammatory cell infiltration in eady stage of implantation, and no significant inflammatory cell infiltration in late stage of observation. Fibroblasts were visible in the acellular matrix. In addition, the acellular matrix material did not exhibit toxic effects on surrounding tissues, showing wound stage I healing. Simultaneously,histological sections demonstrated that there were good compatibility of scaffold material and surrounding tissues, without rejection. These indicated that acellular matrix material presented good biocompatibility in animals.

The porous scaffolds for bone tissue engineering were prepared by foam impregnation. The magnesium and aluminum acid phosphates were used as bonder and the hydroxyapatite ((Ca10 (PO4)6(OH)2, HA) powder as raw materials. Scanning electron microscopy (SEM) examination indicated that the 3D interconnected porous structure of the organic foam was replicated well by the scaffolds calcined at high temperature and the structural requirement of tissue engineering was satisfied. XRD analysis showed that the scaffold was composed of HA and Ca7Mg2P6O24 while calcined at 1150 degrees C for shorter time and of (Ca, Mg)3(PO4)2 when the time prolonged to 2 h. There was no peak of CaO found in the scaffolds by XRD. According to the culture in vitro, the scaffold possesses good biocompatibility and certain degree of degradability.
Aluminum Compounds ; chemistry ; Biocompatible Materials ; Bone Substitutes ; chemistry ; Calcium Phosphates ; chemistry ; Durapatite ; chemistry ; Phosphates ; chemistry ; Porosity ; Tissue Engineering