The Study Of The Ability Of Marrow Stromal Cell Cultured In Vitro For Bone Formation And A Preliminary Study Of Tissue Engineering Bone

Bone tissue engineering main problems are seed cells and its carriage.Rabbit marrow stromal cells were cultured in vitro induced by TGF- B , rhBMP-2 and the characteristics of bone formation of marrow cells were investigated in our experiment. By complexing the induced rabbit marrow stromal cells with the biodegradation material in vitro, implanting the complex in nude mouse, the ability for bone formation of this complex was observed.Part I: Rabbit marrow stromal cells were separated and cultured in vitro. Induced with dexamethasone, the proliferation status ,the alkaline phosphatase level of cells and MTT chromometry were investigated. The results were analyzed with statistics. The number of cells, OD value of MTT chromometry and alkaline phosphatase staining showed certain changing tendency under different concentration of dexamethasone. OD value of alkaline phosphatase staining increased with the concentration of dexamethasone increased. Besides, the cell number and OD value of MTT chromometry reached a climax under the concentration 10-8M of dexamethasone. This indicated dexamethasone has wonderful ability to induce marrow stromal cells into osteoblasts in vitro culture.Part II: The effect of rhBMP-2 and TGF- B on the proliferation and differentiation of cultured rabbit marrow stromal cells was observed. By cultured the marrow stromal cells with rhBMP-2 or TGF- P in vitro respectively, MTT chromometry and alkaline phosphatase staining were employed to detect the effects of cell proliferation and differentiation. We can see from the experiments that the effects of rhBMP-2 and TGF- P on marrow stromal cells were different. rhBMP-2 functioned mainly to induce cells differentiation and TGF- 3 to promote cells proliferation.Part III: Dexamethasone was used to induce the marrow stromal cells to marrow stromal osteoblasts(MSOs) and then MSOs as seeds cells were cultured on the poly- B -hydroxybutyrate carriage to form a MSO/PHB artificial bone complex. The complex was implanted in nude mouse. By histology and image analysis, the bone formation status was investigated. MSO/PHB complex had a obvious effect of ectopic osteogenesis including intramembranous ossification and cartilaginous ossification in nude mouse. The main effect was intramembranous ossification and the volume of bone increased as time passed superior to MSC/PHB group.Through above experiments we can make a conclusion that marrow stromal cells can be induced in vitro into mso and MSO can thus be applied in bone engineering. Once MSO are complxed with proper carriage, the new complex indicates obvious bone formation effects and have a excellent application prospect in bone tissue engineering.