目的探讨建立转座子载体过表达外源肿瘤坏死因子相关凋亡诱导配体(TRAIL)的人脐带来源间充质干细胞(hUC-MSCs)转基因细胞系及其应用于脑胶质瘤裸鼠模型的疗效。方法自主专门设计的PiggyBac转座子过表达系统,通过嘌呤霉素(puromycin)抗...目的探讨建立转座子载体过表达外源肿瘤坏死因子相关凋亡诱导配体(TRAIL)的人脐带来源间充质干细胞(hUC-MSCs)转基因细胞系及其应用于脑胶质瘤裸鼠模型的疗效。方法自主专门设计的PiggyBac转座子过表达系统,通过嘌呤霉素(puromycin)抗性筛选制备稳定表达TRAIL基因的靶向HER2型和非靶向型的2种转基因细胞。将带有萤火虫荧光素酶标记的脑胶质瘤细胞(U87MG-FLUC)接种于免疫缺陷性小鼠(BALB/c-nu/nu)颅内,接种剂量为1×10^(6)个/只,接种7 d后利用小动物活体成像仪对植瘤小鼠脑颅检测,确定颅内肿瘤的大小和位置,然后将胶质瘤裸鼠分为4组(n=8),分别注射2种表达TRAIL转基因hUC-MSCs(分别命名为target-TRAIL和untarget-TRAIL组),以及只注射非转基因hUC-MSCs(接种剂量均为1×10^(6)/只)或PBS(分别命名为WT-MSCs和PBS组,作为阴性对照),每周用小动物活体成像仪监测肿瘤信号的变化情况,约检测34周。结果2种转基因细胞经过6次传代扩增后能稳定表达TRAIL基因,流式检测:绿色荧光蛋白(GFP)阳性(共表达TRAIL基因)的细胞比例达到93%97%,且经过6次传代后均为MSC相关表面标志物CD34、CD45、HLA-DR阳性率<0.1%,CD90阳性率>99%,CD73阳性率>98%,CD105阳性率>60%。中位生存期(d):胶质瘤裸鼠经颅内注射untarget-TRAIL、target-TRAIL、WT-MSCs或PBS组分别为41 vs 39 vs 24 vs 23(P<0.05)。结论过表达TRAIL转基因的hUC-MSCs-TRAIL细胞明显延长移植了脑胶质瘤的裸鼠的生存时间。展开更多
The present study aimed to investigate the targeting effect of H7K(R2)2-modified pH -sensitive liposomes on U87-MG cells. Using coumarin-6 as a fluorescence probe, we prepared H7K(R2)2-modified p H-sensitive lipos...The present study aimed to investigate the targeting effect of H7K(R2)2-modified pH -sensitive liposomes on U87-MG cells. Using coumarin-6 as a fluorescence probe, we prepared H7K(R2)2-modified p H-sensitive liposomes(designated as coumarin-6-PSL-H7K(R2)2). The flow cytometry assay was used to evaluate the effect of H7K(R2)2 proportions on the cellular uptake and endocytosis pathways of coumarin--6--PSL--H7K(R2)2 on U87-MG cells. The circular dichroism(CD) spectroscopy assay was used to investigate the secondary structures of H7K(R2)2 peptide at pH 7.4 and H 6.8, respectively. Our results indicated that the 2.5% proportion of H7K(R2)2 in the coumarin-6--PSL-H7K(R2)2 was superior to those of 1% and 3.5% of H7K(R2)2. The uptake of coumarin--6-PSL--H7K(R2)2 on U87--MG cells was not inhibited by filipin, M-β--CD or chlorpromazine. The secondary structure of H7K(R2)2 at pH 6.8 was mostly presented as β--turn. In conclusion, we suggested that the appropriate proportion of H7K(R2)2 in the H7K(R2)2--modified pH--sensitive liposomes could be set at 2.5%. The cellular uptake pathway for H7K(R2)2-modified pH--sensitive liposomes was via the cell penetrating capacity of H7K(R2)2 which responded to acidic condition. The secondary structure of H7K(R2)2 at pH 6.8, which was presented as the shape of hairpin, might be mainly responsible for its targeting and cell penetrating effect.展开更多
文摘目的探讨建立转座子载体过表达外源肿瘤坏死因子相关凋亡诱导配体(TRAIL)的人脐带来源间充质干细胞(hUC-MSCs)转基因细胞系及其应用于脑胶质瘤裸鼠模型的疗效。方法自主专门设计的PiggyBac转座子过表达系统,通过嘌呤霉素(puromycin)抗性筛选制备稳定表达TRAIL基因的靶向HER2型和非靶向型的2种转基因细胞。将带有萤火虫荧光素酶标记的脑胶质瘤细胞(U87MG-FLUC)接种于免疫缺陷性小鼠(BALB/c-nu/nu)颅内,接种剂量为1×10^(6)个/只,接种7 d后利用小动物活体成像仪对植瘤小鼠脑颅检测,确定颅内肿瘤的大小和位置,然后将胶质瘤裸鼠分为4组(n=8),分别注射2种表达TRAIL转基因hUC-MSCs(分别命名为target-TRAIL和untarget-TRAIL组),以及只注射非转基因hUC-MSCs(接种剂量均为1×10^(6)/只)或PBS(分别命名为WT-MSCs和PBS组,作为阴性对照),每周用小动物活体成像仪监测肿瘤信号的变化情况,约检测34周。结果2种转基因细胞经过6次传代扩增后能稳定表达TRAIL基因,流式检测:绿色荧光蛋白(GFP)阳性(共表达TRAIL基因)的细胞比例达到93%97%,且经过6次传代后均为MSC相关表面标志物CD34、CD45、HLA-DR阳性率<0.1%,CD90阳性率>99%,CD73阳性率>98%,CD105阳性率>60%。中位生存期(d):胶质瘤裸鼠经颅内注射untarget-TRAIL、target-TRAIL、WT-MSCs或PBS组分别为41 vs 39 vs 24 vs 23(P<0.05)。结论过表达TRAIL转基因的hUC-MSCs-TRAIL细胞明显延长移植了脑胶质瘤的裸鼠的生存时间。
基金Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20120001110012)the National Basic Research Program of China(973 Program,Grant No.2013CB932501)National Natural Science Foundation of China(Grant No.81172992)
文摘The present study aimed to investigate the targeting effect of H7K(R2)2-modified pH -sensitive liposomes on U87-MG cells. Using coumarin-6 as a fluorescence probe, we prepared H7K(R2)2-modified p H-sensitive liposomes(designated as coumarin-6-PSL-H7K(R2)2). The flow cytometry assay was used to evaluate the effect of H7K(R2)2 proportions on the cellular uptake and endocytosis pathways of coumarin--6--PSL--H7K(R2)2 on U87-MG cells. The circular dichroism(CD) spectroscopy assay was used to investigate the secondary structures of H7K(R2)2 peptide at pH 7.4 and H 6.8, respectively. Our results indicated that the 2.5% proportion of H7K(R2)2 in the coumarin-6--PSL-H7K(R2)2 was superior to those of 1% and 3.5% of H7K(R2)2. The uptake of coumarin--6-PSL--H7K(R2)2 on U87--MG cells was not inhibited by filipin, M-β--CD or chlorpromazine. The secondary structure of H7K(R2)2 at pH 6.8 was mostly presented as β--turn. In conclusion, we suggested that the appropriate proportion of H7K(R2)2 in the H7K(R2)2--modified pH--sensitive liposomes could be set at 2.5%. The cellular uptake pathway for H7K(R2)2-modified pH--sensitive liposomes was via the cell penetrating capacity of H7K(R2)2 which responded to acidic condition. The secondary structure of H7K(R2)2 at pH 6.8, which was presented as the shape of hairpin, might be mainly responsible for its targeting and cell penetrating effect.