A Generic Coordination Assembly-Enabled Nanocoating of Individual Tumor Cells for Personalized Immunotherapy

A generic and effective tumor cells encapsulation strategy enabled by metal-organic coordination is developed to prepare a vaccine for personalized immunotherapy. Specifically, an epigallocatechin-3-gallate (EGCG)-Al(III) coordination layer is in situ formed onto individual living cells in aqueous phase and the process can be completed within an hour. 98% of proteins in the cells are entrapped within the microparticles, which are endowed with high antigens loading capacity. The microparticles enhance the uptake efficiency of antigens, protect antigens from degradation in vivo, and delay the retention time of antigens in the lymph nodes. Moreover, dendritic cells (DCs) activation is triggered by the microparticles, and simultaneously, the expression of costimulation marker on DCs and the production of Th1-related cytokines are significantly upregulated. Moreover, six kinds of tumor cells are utilized and successfully coated with the EGCG/Al(III) layer, suggesting the generalization of this strategy. More importantly, the microparticles exhibit a comparative antitumor effect with polyinosinic-polycytidylic acid (PolyI:C) in B16 pulmonary metastasis model. Overall, the encapsulation strategy enabled by metal-organic coordination can be potentially useful for personalized immunotherapy customized to individual patient's tumor cells.