Isolation, culture and identification of rabbit bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: Both density gradient centrifugation and adherence method arc frequently used to isolate bone marrow mesenchymal stem cells (BMSCs).OBJECTIVE: To investigate the approaches to isolate, culture and identify the rabbit BMSCs in vitro by the combination of den,ity gradient centrifugation and adherence method. DESIGN, TIME AND SETTING: Contrast cytological study, which was performed in Central Laboratory of Shanghai 6th People's Hospital between October 2007 and March 2008.MATERIALS: Six 2-week-old rabbits were selected for BMSCs preparation and primary culture; Percoll separating medium (1.073 kg/L) was also used for this study.METHODS: BMSCs were separated and purified with Percoll separating medium by density gradient centrifugation and adherence method. The three-, five-, seven-, and nine-passage BMSCs were counted for growth curve. MAIN OUTCOME MEASURES: Morphological features and growth states of primary and passage cells were observed under inverted microscope. Indirect immunofluorescence of CD44 and CD34 antibodies were used to examine the stem cells. CD44 staining was positive, and CD34 staining was negative, suggesting the extracting and purifying cells were BMSCs. RESULTS: The passage BMSCs were uniformly distributed like fusiform shape, which were more uniform than primary cultured cells. The BMSCs grew productively and proliferated rapidly; meanwhile, the nucleolus was clear, caryopla.sm was in a large proportion, morphological features were uniform, ceils like bostrychoid or whirlpool were arranged parallelly, and the five-pa.ssage cells were not changed remarkably. Proliferation was decreased gradually with the passage increasing; especially, the proliferation of three-five-passage cells was the strongest. The separated cells expressed CD44 but not CD34. CONCLUSION: High-purified rabbit BMSCs are obtained by both density gradient centrifugation and adherence method.