Effect Of Tumor Autophagy Antigens Combined With Aluminum Hydroxide Nanoparticles Loading DCs As Anti-tumor Vaccines

[Objective]:Due to the high-quality immunogenicity of tumor-derived auto-phagosomes(DRibbles),we aimed to explore the anti-tumor ability and mechanism of DRibbles-loaded dendritic cells(DRibble-DCs).We also want to explore the feasibility of delivering tumor antigens and enhancing the antigen cross-presentation of dendritic cells(DCs)by aluminum hydroxide nanoparticles with polyethyleneimine modification(LV@HPA/PEI).[Method]:DRibbles extracted from the tumor cell lines express specific LC3-II and ubiquitination(Ub)marks.Immunization of mice with the DRibble-loaded dendritic cell(DRibble-DCs)vaccines led to the proliferation and differentiation of CD3+CD4+IFN-?+ and CD3+CD8+IFN-?+ T cells.The expression of proteins in endoplasmic reticulum stress(ERS)pathways was determined by Western blot.The LV@HPA nanoparticels were modified by PEI firstly.Then,the influence of LV@HPA/PEI on DCs was examined.The distinct expression of ovalbumin(OVA)protein transported into DCs by LV@HPA/PEI was observed by Flow cytometry and Western blot.The biocompatibility of LV@HPA/PEI,maturity and antigen cross-presentation of DCs were observed in vitro.DRibbles combined with LV@HPA/PEI and DCs were immunized mice.The percentage of CD3+CD8+IFN-y+T cells in immunization of mice was determined by Flow cytometry.Additionally,the functional properties of the LV@HPA/PEI-DRibble-DCs vaccine were examined in vivo in tumor-bearing mice.[Result]:Excellent biocompatibility was observed in vitro when DCs were loaded with DRibbles.Lymph nodes and spleen T cells from mice immunized with 2.5?g/mL DRibble-DCs had the best immune effects.Homeostasis and ERS-related proteins of DCs were affected by DRibbles.Moreover,we described LV@HPA/PEI could be functionalized antigen delivery system with notable antigen transport effect and negligible cytotoxicity.It was found that LV@HPA/PEI could be easily internalized into DCs to assist antigen releasing into the cytoplasm.Besides,DCs would mature gradually after loaded with nano-adjuvants,which increased significantly the cytokine IL-12 secretion and surface molecules CD80 and CD86 expression.Interestingly,LV@HPA/PEI-DRibbles loaded DCs could promote the activation of CD3+CD8+IFN-y+ T-cells.In the following in vivo experiments,the vaccine of LV@HPA/PEI-DRibble-DCs significantly inhibited tumor growth and improved the survival rate of the tumor bearing mice.[Conclusion]The results validated the antitumor immune responses to the DRibble-DCs vaccine in vivo and in vitro.The ERS pathway can be affected by DRibbles.We established a high-performance antitumor system of DCs loaded with LV@HPA/PEI-DRibbles,which could be served as potential therapeutic strategy combined the tumor-associated antigen in the cancer immunotherapy.