超顺磁氧化铁纳米颗粒对人牙髓干细胞生物学影响的体内外研究

The effects of superparamagnetic iron oxide nanoparticles on the biological activity of human dental pulp stem cells in vitro and in vivo

目的：探讨不同浓度超顺磁氧化铁纳米颗粒（SPIO）在体内外对人牙髓干细胞（h DPSCs）活力、增殖和成骨分化的影响。方法：用不同浓度SPIO标记h DPSCs后,体外条件下对其活力、增殖、分化等进行观察;然后将细胞/支架复合物植入裸鼠皮下,观察体内条件下SPIO对h DPSCs成骨分化的影响。结果：25、50μg/m L的SPIO不影响h DPSCs的活力,100μg/m L的SPIO抑制细胞活力;25、50μg/m L的SPIO在1~3 d促进细胞增殖,而100μg/m L的SPIO则抑制细胞增殖且促进其凋亡。25μg/m L的SPIO在体外和体内条件下对h DPSCs的成骨分化均无明显影响。结论：25μg/m L的SPIO可以有效标记h DPSCs,在早期可促进其增殖,而对其成骨分化无影响。

AIM：To explore the effects of superparamagnetic iron oxide nanoparticles （SPIO）on the bio-logical activity of human dental pulp stem cells （hDPSCs）in vitro and in vivo.METHODS：hDPSCs were incubated in culture medium with SPIO at 0 μg/mL,25 μg/mL,50 μg/mL and 100 μg/mL respectively for 24 hours.The labe-ling efficiency,viability,proliferation,cell cycle and apoptosis of the cells were examined.The cells labeled by 25 μg/mL SPIO were cultured in osteogenic induction medium and the osteogenic differentiation potential was observed in vitro.hDPSCs and SPIO labled hDPSCs were respectively combined with scaffold and implanted subcutaneous into nude mice,the in vivo bone formation was observed by Van Gieson staining 8 weeks after implantation.RESULTS：25 μg/mL -50 μg/mL SPIO had no influence on the cell vitality but promoted cell proliferation in 1 d -3 d culture. However,100 μg/mL SPIO showed toxic effect on cell vitality and inhibited the proliferation of hDPSCs.For osteogen-ic differentiation,no significant difference was found between control group and 25 μg/mL SPIO group both in vitro and in vivo.CONCLUSION：25 μg/mL SPIO can effectively and safely label hDPSCs,promote cell proliferation and has no influence on osteogenic differentiation.