.bmscs/bmp-2/¦Â-tcp- Sodium Hyaluronate Composite Scaffold For The Experimental Study Of Tissue-engineered Cartilage

ObjectiveTo evaluate rhBMP-2/β-TCP-HA composite scaffold seeded with MSCs as a new biodegradable polymer scaffold for application on the articular cartilage tissue engineering in nude mice in vivo.MethodsSD rats,2 week-old.were killed under sterile condition,MSCs were separated from rats femurs and tibias marrow by plastic adherence methods and purified by controlling the time of digestion combied with adhesion separation.During the purification and proliferation of MSCs in vitro,three groups were established,including experimental group:rhBMP2/β-TCP-HA,control group:rhBMP-2/β-TCP and negative control group:β-TCP composite scaffold.Tertiary- generation rat MSCs were cultured as seed cells and inoculated into composite scaffolds with vacuum aspiration technique.Finally these composite scaffolds were planted in athymic mouse subcutaneously.The specimens harvested were evaluated morphologically and histologically 12 weeks after surgery.Results The specimens harvested in the experimental group were morphologically the thickest and had smooth surface,cartilage-like tissue formation could be seen on the surface of the implants.Microscopic analysis demonstrated complete degradation of the scaffold and rich extracellular matrix formation. The cells were stained positive strongly withGAG and typeⅡcollagen.In control group,microscopic analysis demonstrated partial degradation of scaffold and island-like cartilage formation were observed in composite scaffold.The cells were stained positive withGAG and typeⅡcollagen too.In negative control group,fibrous tissue and adipose tissue can be seen mainly in these scaffolds and small amounts of cartilage tissue were observed on the fringe of implants. The cells were stained negative with GAG and typeⅡcollagen.ConclusionThe rhBMP-2/β-TCP-HA composite scaffold seeded with MSCs may be an effective choice for articular cartilage tissue engineering. ObjectiveTo observe the repairing effect of bone marrow derived mesenchymal stem cells(MSCs)/bone morphogenetic protein-2(BMP-2)/beta tricalcium phosphate-hyaluronate(TCP-HA)composite scaffold on rabbit articular cartilage defects.MethodsMSCs were isolated and expanded from autologous rabbit bone marlow.24 Newzealand White Rabbits were divided into 4 groups:sham group,control groupⅠ,control groupⅡ,experimental group.Full-thickness articular osteochondral defects(4 mm in diameter and 6 mm in depth)were created mechanically in the femur medial condyle of the rabbits.MSCs/rhBMP-2/β-TCP-HA,MSCs/rhBMP-2/β-TCP and MSCs/β-TCP Composite Scaffold were respectively transplanted into the defects of experimental group,control groupⅡand control groupⅠ,the sham group underwent no special treatment.The defects were evaluated morphologically and histologically 12 weeks after surgery. Results:The specimens harvested from experimental group demonstrated a hyaline cartilage formation,the new formed cartilage integrated satisfactorily with adjacent normal cartilage;The control groupⅡdemonstrated a immature hyaline cartilage mixed with fibrous cartilage formation.The control groupⅠjust showed fibrous cartilage formation.The sham group demonstrated no significant repairing effect.The repairing effeft of experimental group was obviously better than that of other groups by Wakitani scale.ConclusionTissue engineering cartilage using MSCs/rhBMP-2/β-TCP-HA composite scaffold may be a promising way for the treatment of cartilage defects.