肿瘤细胞膜与细菌囊泡膜融合的纳米囊泡及其肿瘤效应

Nanovesicles of Tumor Cell Membranes Fused with Bacterial Vesicle Membranes and Their Effects on Tumors

该文主要探讨肿瘤细胞膜与大肠杆菌仿生囊泡(BBV)进行膜融合的纳米囊泡是否可激发抗肿瘤免疫反应。通过Avanti挤出机制备具有两种生物膜特性的融合膜囊泡,采用透射电子显微镜观察囊泡形态,免疫荧光和免疫印迹检测膜提取的成分,电泳和共聚焦激光扫描显微镜(CLSM)观察膜融合。在此基础上,建立TC-1小鼠肿瘤模型,监测小鼠的肿瘤生长,以融合囊泡免疫进行治疗干预,并以酶联免疫斑点技术(ELISPOT)与流式细胞术分析小鼠免疫应答效果。制备物以纳米膜囊泡形式存在;融合膜囊泡不仅显示两种膜成分的荧光共定位,而且具备两种膜的蛋白成分,免疫荷瘤抑制了小鼠肿瘤的生长,增强了表达IFN-γ的肿瘤特异的脾细胞应答水平,降低了免疫抑制性的髓源性抑制细胞水平。两种生物膜挤压融合形成的纳米融合膜囊泡可激发抗肿瘤免疫,为基于生物膜系统的肿瘤疫苗研究提供了基础。

This study was to investigate whether the nanoscale vesicles prepared by fusing tumor cell membrane and BBV(bacterial biomimetic vesicles)of Escherichia coli have the capability of activating anti-tumor immune responses and inhibiting tumor growth.The vesicles with the immunological properties of two different biomembrane were prepared by Avanti extrusion mechanism.Transmission electron microscopy was used to observe the morphology of the vesicles,immunofluorescence assays and Western blot were performed to analyze the extraction of membranes.SDS-PAGE and CLSM(confocal laser scanning microscopy)were employed to detect the fusion of the two membranes.On this basis,TC-1 mouse tumor model was established;the tumor growth of the mouse was monitored,and the immune response of the mouse was analyzed by ELISPOT(enzyme-linked immunospot assay)and flow cytometry.The preparation existed in the form of nanofilm vesicles.The fusion membrane vesicles not only showed the fluorescence colocalization of the two membrane components,but also possessed the protein components of the two membrane components.After immunization of tumor-bearing mouse,the fusion membrane vesicles inhibited the tumor growth,enhanced the tumor-specific spleen cell response expressing IFN-γ,and reduced the level of immunosuppressive myeloid-derived suppressor cells.Nanomembrane vesicles formed by the extrusion and fusion of the two biofilms can stimulate anti-tumor immunity provides the basis for tumor vaccines based on biofilm system.