肿瘤疫苗通过激活抗原特异性T细胞特异性识别和清除肿瘤细胞，在肿瘤免疫治疗领域受到越来越多的关注。理论上来说一个有效的疫苗应该共递送肿瘤特异性抗原和免疫佐剂至树突状细胞（DCs），同时引发DCs的活化和抗原提呈，进而激发强烈的抗原特异性T细胞的应答，从而有效杀伤肿瘤细胞。在本项目中，我们拟发展一种新的肿瘤疫苗体系，将肿瘤细胞膜和细菌外膜囊泡制备成混合膜，包被在筛选的PLGA NPs内核上制成纳米疫苗。该疫苗体系中的混合膜可同时向DCs提供肿瘤抗原和佐剂，因此预测其可引发强烈的DCs活化和抗原加工提呈，并最终引起抗原特异性CD8+ T细胞的增殖和活化。而后我们将研究该纳米疫苗的肿瘤预防和治疗效果。项目将详细研究该纳米疫苗体系对免疫系统的激活能力，为开发出高效的肿瘤疫苗提供理论基础。

Cancer vaccines, by educating the immune system to specifically recognize and eliminate tumor cells, have attracted more and more attention in tumor immunotherapy. Ideally, a fully effective vaccine should co-deliver tumor-specific antigens and adjuvants to DCs for simultaneous activation and antigen presentation of DCs and subsequently elicit anti-tumor CD8+ T cell responses. Here, we report a strategy to develop a nanovaccine system called as bactusome by coating cancer cell membranes (CCMs) and bacterial outer membrane vesicles (OMVs) hybrid membranes (CCM-OMVs) on the selected PLGA NPs. CCMs contained various tumor-specific antigens and OMVs preserved multiple kinds of immunostimulatory components from parental bacteria, thus the obtained bactusome significantly promoted the maturation and tumor-specific antigen presentation of DCs and eventually mounted tumor-specific CD8+ T cell responses. Immunization with the bactusome itself showed a great preventive effect on tumor development and combination of the bactusome with immune checkpoint blockade therapy further performed a good therapeutic efficacy on established tumors. Overall, the bactusome cancer nanovaccine system offers a good method for cancer immunotherapy and might be developed as personalized cancer nanovaccine.