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目的 探讨上转换纳米粒子(upconversion nanoparticles,UCNPs)介导的光动力疗法对大鼠脊髓星形胶质细胞的体外杀伤效应.方法 体外无菌条件下取新生SD大鼠脊髓组织,采用机械吹打及胰酶消化法制成细胞悬液,通过差速贴壁和恒温摇床震荡去除杂细胞,利用GFAP免疫荧光染色鉴定,成功分离培养大鼠脊髓星形胶质细胞.采用MTT法检测不同浓度UCNPs-MC540[以上转换纳米为载体和能量转换器,并使用偶联光敏剂部花青540(Merocyanine 540)构建的复合物]、不同能量980 nm激光照射对脊髓星形胶质细胞活力的影响以及在980 nm近红外激光照射下UCNPs-MC540介导的光动力疗法的细胞杀伤效应;应用浓度为200 μg/ml的UCNPs-MC540培养液与星形胶质细胞共培养12h后,给予2 000 J/cm2的980 nm近红外激光进行照射,以同样条件培养而未作激光照射光动力治疗的细胞作为对照组;分别制作透射电镜标本,透射电子显微镜下观察细胞形态改变.结果 不同浓度UCNPs-MC540及不同照射剂量980 nm激光照射处理后细胞存活率的差异无统计学意义.在浓度100 μg/ml的UCNPs-MC540作用细胞12h后分别给予不同能量激光照射,细胞存活率随着激光剂量的增加而下降,差异有统计学意义.不同浓度的UCNPs-MC540作用于细胞12h后予2000 J/cm2能量激光照射,随着UCNPs-540浓度的增加,细胞的存活率降低,差异有统计学意义.与未作激光照射光动力治疗细胞的对照组比较,细胞与浓度为200 μg/ml的UCNPs-MC540共培养,能量为2 000 J/cm2激光照射后,透射电镜检查显示细胞呈凋亡表现,形成具有特征性的凋亡小体.结论 由上转换荧光纳米NaYF∶Er,Yb与光敏剂MC540连接的纳米复合物UC-NPs-MC540介导的光动力疗法对星形胶质细胞有良好的杀伤效果,其机制可能为诱导细胞发生凋亡,为脊髓损伤的治疗提供新的思路,扩大光动力疗法的研究应用范围.“,”Objective To investigate the phototoxicity effects of the nanocompound of upconversion nanoparticles (UCNPs) on rat astrocytes in vitro.Methods The spinal astrocytes cells were cultured successfully in vitro and then incubated with the UCNPs-MC540 of various concentrations and exposured 980 nm infrared laser irradiation of different energy densities.The cell survival rates of each group were detected by MTT assay.The cellular morphology was observed via transmission electron microscope after photodynamic therapy.Results UCNPs-MC540 of different concentrations without laser irradiation or laser of different energy had no significant effects on cell survival rates.when cells incubated with 100 μg/ml UCNPs-MC540 for 12 h underwent laser irradiation of different energy,the cellular survival rates significantly decreased with the increased energy densities.when the cells incubated with UCNPs-MC540 of various concentrations for 12 h underwent laser irradiation of 2 000 J/cm2,the cellular survival rates significantly decreased with the increased concentrations.Compared with controls,the TEM show the apoptosis sign in the cells incubated with 200 μg/ml UCNPs-MC540 after laser irradiation of 2 000 J/cm2.Conclusion The UCNPs-MC540 mediated photodynamic therapy have effective killing effect on astrocytes by the mechanism of induction the apoptosis.