Effects of different isolation methods on chondrogenic differentiation of bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: At present, there has been no definite experiment systemically evaluating adherent separation and density gradient centrifugation to isolate bone marrow mesenchymal stem cells (BMSCs). Whether the two methods produce different influences on BMSC induction and differentiation remains unclear.OBJECTIVE: This study was designed to verify difference of these two isolation methods in chondrogenic differentiation of BMSCs.DESIGN, TIME AND SETTING: A controlled observation was performed at the Shengjing Hospital Affiliated to China Medical University from March to September 2005. MATERIALS Twenty Japanese big-ear rabbits, aged 2-3 months, weighing 1.2-2.0 kg, were included for this study. METHODS: BMSCs were isolated by adherent separation and density gradient centrifugation. Two groups of BMSCs were taken from the same passage and induced towards chondrogenic differentiation with transforming growth factor beta 1. MAIN OUTCOME MEASURES: Growth of BMSCs was observed under an inverted microscope to draw growth curves; Type II collagen expression was detected by immunohistochemistry. Type II collagen mRNA expression was determined by in situ hybridization. RESULTS: The growth curves demonstrated that cellular growth velocity of the two groups tended to be the same. Immunohistochemistry results showed that the efficiency of adherent separation and density gradient centrifugation for promoting chondrogenic differentiation of BMSCs was 76.1% and 77.7%, respectively, and in situ hybridization results showed that the efficiency was 70.3% and 71.0%, respectively. No significant difference in differentiation efficiency existed between the adherent separation and the density gradient centrifugation. CONCLUSION: Adherent separation and density gradient centrifugation had no different influences on BMSC growth and chondrogenic differentiation.