Suitable concentration of alginate with xenograft for constructing bone tissue engineering carrier / 中国组织工程研究

ABSTRACT

BACKGROUND:The structure of tissue engineering carrier affects the bio-action of cells greatly.OBJECTIVE: To investigate the biological characteristics of bone marrow stem cells (MSCs) in different concentrations of alginate combined with de-antigen bone xenograft (DBX).DESIGN: Observational trial.SETTING: PLA Institute of Trauma and Orthopedics, the Fourth Military Medical University of Chinese PLA.MATERIALS Alginate, calcium chloride, MSCs, bone xenograft.METHODS: Bovine cancellous bone was out into cubes, which were degreased, deproteinized and then lyophilized.Cubes in pore size within 300-500 μm were selected for use after ethylene oxide sterilization. The purified sodium alginate was dissolved in DMEM cell culture medium of concentrations as different as 0.5%, 2%, 8% and 16%; 1×1012 L-1 induced MSCs were blended with isopyknic alginate-DMEM and compounded with DBX at a status of 0.5 Mpa negative pressure for 5 minutes in order to make a cell suspension fully fill into the pores of the cancellous bone. Then alginate was crosslinked with 50 g/L calcium gluconic acid for 30 seconds. The complex was put into a CO2 incubator and cultured for 4 days. The gel compound and cell growth in the pores of the complex were grossly observed with an inverted microscope. Status of cell growth in the complex with different concentrations of alginate was observed with scanning electron microscopeMAIN OUTCOME MEASURES: Compound status of alginate and bone xenograft, cell growth status and matrix secretion in compound carries.RESULTS: When the concentration of alginate was 0.25% or 1%, alginate was equally combined in DBX, while that of 4% and 8% only combined on the surface of cancellous bone. After in vitro cultured for 4 days, alginate of 0.25% were broken off from DBX surface. But alginate of 1% was equally combined with DBX pores with cells secreting well in alginate. Development of cells in alginate of 4% was restricted and no cells were seen in alginate of 8%.CONCLUSION: Alginate of 1% is suitable for constructing the carrier of bone tissue engineering with bone xenograft.