不同接种浓度的骨髓基质细胞体外生物学活性的研究

A Study on the Effect of Biologic Activity by Bone Marrow Stromal Cells with Different Seeding Density in Vitro

目的研究不同初始接种浓度对Beagle犬骨髓基质细胞（Bone marrow stromal cells，BMSCs）体外成骨能力的影响。方法将体外培养扩增的第1代BMSCs制成不同浓度（5×10^7cells／mL、5×10^6cells／mL、5×10^5cells／mL）的细胞悬液，分别接种于60mm培养皿，观察矿化结节形成的时间；并分别与胶原膜BME-10X复合，比较2d、5d、7d的碱性磷酸酶（Alkaline phosphatase，ALP）活性。结果细胞初始接种密度越高，形成矿化结节的时间就越短；在细胞载体复合物中，同一浓度组的ALP活性随培养时间的延长而增加；在相同天数，5×10^7cells／mL组与5×10^6cells／mL组、5×10^5cells／mL组之间ALP含量有显著差异，而5×10^6cells／mL组与5×10^5cells／mL组之间则无显著差别。结论BMSCs体外的成骨能力与细胞的接种密度有关，初始接种密度越高，其体外的成骨能力就越强。

Objective To evaluate the effect on the osteogenic potential of bone marrow stromal cells （BMSCs） with different initial seeding density in vitro. Methods BMSCs isolated from Beagle were cultured-expanded, subcuhured. The different density of the first passage （P1） BMSCs suspensions were prepared at 5×10^7 cells/mL, 5×10^6 eells/mL or 5×10^5 cells/mL. BMSCs in different suspensions were plated into 60 mm dishes, the formation process of mineral nodules was observed with microscope. The alkaline phosphatase （ALP） activity of BMSCs which combined with collagen membranes in different density were detected and compared on 2^nd day, 5^th day and 7^th day. Results Higher density resulted in better mineralized tissue formation early. In these complex, higher ALP activity were detected following the culture days at the same density. The ALP activity were significant different in the 5 × 10^5 cells/mL, 5×10^6 cells/mL and 5×10^7 cells/mL groups at the same day, but there was no significant different between the first two groups. Conclusion The osteogenic capacity of BMSCs has cell density dependent. The higher concentrations resulted in the stronger activity of osteogenic potentiality in vitro.