具有聚集诱导发光性质的脂滴靶向光敏剂用于骨肿瘤细胞成像和光动力治疗

Lipid droplet-targeted photosensitizers with aggregation-induced emission properties for bone tumor cell imaging and photodynamic therapy

目的探讨聚集诱导发光材料LD-Orange对骨肿瘤细胞的生物相容性,肿瘤细胞内吞能力,细胞器定位和对骨肿瘤细胞的光动力杀伤效果。方法采用骨肿瘤细胞系143B作为模型细胞,应用激光共聚焦成像探究LD-Orange与143B细胞孵育后的荧光成像以评估其内吞性能,用商业脂滴染料尼罗红(Nile Red)和LD-Orange共染,应用激光共聚焦成像确定其亚细胞定位并评估其细胞器靶向性能,用DCFH-DA作为活性氧指示剂,探究LD-Orange的细胞内、外活性氧产生能力,用Calcein-AM/碘化丙锭(PI)细胞活性检测试剂盒和噻唑蓝(MTT)实验评估研究细胞杀伤和生物相容性,采用t检验确定实验组和对照组之间的显著性。结果LD-Orange能够被骨肉瘤细胞系143B内吞,定位于细胞脂滴中,且其与商业脂滴染料具有95%的共染率,是一种靶向脂滴的染料。在30 mW/cm^(2)的低功率普通LED白光的照射下,LD-Orange表现出优异的活性氧产生能力。MTT细胞毒性实验表明,与对照组143B细胞存活率比较LD-Orange为15μmol/L时,143B细胞存活率不受影响(t=0.474,P>0.05),差异无统计学意义。而实验组经过白光(30 mW/cm^(2))照射后,143B细胞的杀伤率为98.27%(t=39.610,P<0.01)。结论LD-Orange具有良好的生物相容性,其能够被骨肉瘤细胞143B内吞,具有高的脂滴靶向性,具备较为优异的活性氧产生能力。LD-Orange对骨肿瘤细胞的脂滴良好的靶向成像能力和荧光成像引导下对骨肉瘤细胞的光动力治疗效果确认其为一种有效的脂滴细胞器靶向性光敏剂,为协助下的骨肉瘤外科手术等治疗手段的效果提升提供了较为有效的尝试。

Objective To investigate the biocompatibility of the aggregation-induced luminescent material lipid droplet(LD)-Orange on bone tumor cells,tumor cell endocytosis,organelle localization and photodynamic killing of bone tumor cells.Methods The bone tumor cell line 143B was used as a model cell,and laser confocal imaging was applied to explore the fluorescence imaging of LD-Orange after incubation with 143B cells to assess its endocytosis performance,co-staining with commercial lipid droplet dye Nile Red and LD-Orange,and laser confocal imaging was applied to determine its subcellular localization and assess its organelle-targeting performance,and the DCFH-DA was used as a reactive oxygen species indicator to explore the intracellular and extracellular reactive oxygen species generating capacity of LD-Orange,and the cell killing and biocompatibility of the study cells were assessed by Calcein-AM/propidium iodide(PI)cell activity assay kit and methyl thiazolyl tetrazolium(MTT)assay.The t-test was used to determine the significance between the experimental and control groups.Results LD-Orange could be endocytosed by osteosarcoma cell line 143B,localized the lipid droplets of bone tumor cells,and had 95%co-staining with commercial lipid droplet dyes.Under the irradiation of low-power ordinary LED white light at 30 mW/cm^(2),LD-Orange showed excellent reactive oxygen species generation ability.MTT cytotoxicity assay showed that the survival rate of 143B cells treated with LD-Orange at 15μmol/L was unaffected as compared with that of control 143B cells(t=0.474,P>0.05).The killing rate of 143B cells in the experimental group after white light(30 mW/cm^(2))irradiation was 98.27%(t=39.610,P<0.01).Conclusion LD-Orange has good biocompatibility,can be endocytosed by osteosarcoma cells 143B,has high lipid droplet targeting rate,and has excellent reactive oxygen species generating capacity.LD-Orange’s good targeting imaging of lipid droplets on bone tumor cells and fluorescence imaging-guided photodynamic therapy on osteosarcoma cells confirm that LD-Orange is an effective LD organelle-targeting photosensitizer,providing a more effective attempt to enhance the effect of assisted surgical and other therapeutic means for osteosarcoma.