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为了模拟肠道小肠上皮-血管屏障,我们建立了一个基于肠道生理结构的Caco-2/EAhy926串联复合模型.基于此模型,我们对纳米粒的跨膜转运进行了研究,并且与传统小肠上皮细胞模型做了比较.本研究中,使用粒径为30 nm左右的Fe3O4纳米粒作为模式制剂开展研究,它有着均匀的粒径分布和很好的单分散性.在孵育浓度下,此制剂对Caco-2细胞和EAhy926细胞几乎没有毒性.Caco-2/EAhy926串联复合模型是通过将Caco-2细胞单层和EAhy926细胞单层连接建立的.基于FD4渗透和跨膜电阻(TEER)的研究表明,在一定的培养时间范围内,所有的细胞模型都能保持完整.使用Claudin-4和VE Cadherin,验证了紧密连接的存在.F-actin微丝蛋白的完整性表明了存在着良好的细胞内连接.研究表明,与Caco-2模型和EAhy926模型相比,串联模型对FD4和Fe3O4纳米粒的转运造成了更大的阻碍.并且发现,EAhy926细胞单层有着很好的渗透性,串联模型对纳米材料的阻碍主要是由于Caco-2细胞单层.总的来说,此串联复合模型使我们能够同时对纳米粒在小肠上皮层和内皮层的转运进行评价,提供了一个研究小肠生物-纳米相互作用的好方法.“,”Based on the physiological structure of the intestine,a Caco-2/EAhy926 tandem compound model was constructed in order to simulate the intestinal-vascular barrier.This model was applied in the study of transcytosis of nanoparticles,and it was compared with the traditional intestinal cell model in the whole study.Briefly,Fe3O4 nanoparticles with a size about 30 nm were used as model nanoparticles,which remained steady during transcytosis.The nanoparticles hardly had cytotoxicity to Caco-2 cells and EAhy926 cells within the incubation concentrations.The cell tandem model was established by connecting upper Caco-2 monolayer and lower EAhy926 monolayer.Based on the FD4 permeability or TEER,all cell models remained integrity within certain period of culture time.The expression of Claudin-4 or VE Cadherin demonstrated the presence of tight junctions.The intact morphology of microfilament F-actin indicated the favorable intracellular connection.It was found that the two-layer cell tandem model created a bigger barrier for the transcytosis of FD4 than Caco-2 and EAhy926 monolayer models,and the translocation of Fe3O4 nanoparticles showed a similar pattern.Interestingly,we found that the main barrier of tandem model for nanoparticles was caused by the upper Caco-2 cell monolayer,while the lower layer of EAhy926 monolayer remained high permeability.Generally,the cell tandem compound model established here enabled us to evaluate the impact of both intestinal epithelial and endothelial layer on transcytosis,and it might provide a novel approach to study bio-nano interaction in the intestine.