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

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.

CSTR: 32200.14.cjcb.2023.01.0004