背景:与传统的有机荧光染料相比,量子点呈现出良好的生物标记特性,尤其在细胞标记、临床靶向生物成像等领域呈现出独特的光学特性.目的:观察CdSe/ZnS量子点与单核-巨噬细胞的生物相容性.方法:将巨噬细胞RAW264.7接种于96孔板中,分3组培养,分别加入0,50,100 mg/L的CdSe/ZnS量子点干预,培养1 h或2 h,流式细胞仪检测荧光信号;培养0-24 h,流式细胞仪检测50 mg/L CdSe/ZnS量子点标记巨噬细胞的荧光信号强度;培养18 h,定量PCR检测巨噬细胞内肿瘤坏死因子α及白细胞介素1β的水平;培养18 h,MTT法检测巨噬细胞增殖,流式细胞仪检测细胞凋亡.结果与结论:①荧光信号强度与CdSe/ZnS量子点的质量浓度呈正相关,并且随着标记时间的延长,荧光信号强度增强;②经50 mg/L CdSe/ZnS量子点标记后,随着时间的延长,巨噬细胞的荧光信号不断增强,在18 h达到峰值;③与0 mg/L量子点组比较,50,100 mg/L量子点组可显著促进巨噬细胞内肿瘤坏死因子α及白细胞介素1β的表达(P〈0.01或P〈0.05);100 mg/L量子点组肿瘤坏死因子α表达高于50 mg/L量子点组(P〈0.01);50,100 mg/L量子点组白细胞介素1β表达无差异;④50,100 mg/L CdSe/ZnS量子点组细胞增殖强于0 mg/L量子点组(P〈0.05),50,100 mg/L CdSe/ZnS量子点组细胞增殖无差异;⑤50,100 mg/L CdSe/ZnS量子点对巨噬细胞的凋亡无明显影响;⑥结果表明,CdSe/ZnS量子点可活化巨噬细胞,促其增殖与分泌炎症因子,但不影响其凋亡.
BACKGROUND: Compared with the traditional organic fluorescent dyes, quantum dots present good biomarker characteristics. Especially, quantum dots for cell labeling and targeted bioimaging present unique optical properties.OBJECTIVE: To investigate the biocompatibility of CdSe/ZnS quantum dots with mononuclear macrophages.METHODS: The macrophages RAW264.7 were inoculated into 96-well plates containing 0, 50, 100 mg/L CdSe/ZnS quantum dots for 1 or 2 hours. Then, the fluorescent signal was detected by flow cytometry. After 0-24 hours of culture,the fluorescence signal intensity of the macrophages cultured with 50 mg/L CdSe/ZnS quantum dots was detected by flow cytometry. After 18 hours of culture, quantitative PCR was used to detect the levels of tumor necrosis factor α and interleukin 1β in macrophages, and macrophage proliferation cell apoptosis were detected by MTT and flow cytometry,respectively.RESULTS AND CONCLUSION: The fluorescence signal intensity was positively correlated with the mass concentration of CdSe/ZnS quantum dots, and the intensity of the fluorescent signal was increased with the labeling time. After labeling using 50 mg/L CdSe/ZnS quantum dots, the fluorescence signal of macrophages increased continuously with time, and reached the peak at 18 hours. Compared with 0 mg/L quantum dot group, 50, 100mg/L quantum dot groups could significantly promote the expression of tumor necrosis factor α and interleukin 1β in macrophages (P 〈 0.01 or P 〈 0.05).The level of tumor necrosis factor α in the 100 mg/L quantum dot group was higher than that in the 50 mg/L quantum dot group (P 〈 0.01). The expression of interleukin-1β showed no difference between 50 and 100 mg/L quantum dot groups.The cell proliferation in the 50 and 100 mg/L CdSe/ZnS quantum dot groups was significantly higher than that in the 0 mg/L quantum dot group (P 〈 0.05), but there was no difference between the former two groups. In addition, 50 and 100 mg/L CdSe/ZnS quantum dots had no significant effect on