Detachable Nanoparticle-Enhanced Chemoimmunotherapy Based on Precise Killing of Tumor Seeds and Normalizing the Growing Soil Strategy.

Although immunogenic cell death (ICD)-based chemoimmunotherapy elicits an immune response, it always focuses on eliminating "seeds" (tumor cells) but neglects "soil" (tumor microenvironment, TME), leading to tumor growth and metastasis. Herein, a type of detachable core-shell nanoplatform (DOX@HA-MMP-2-DEAP/CXB) is developed, which could swell in the acidic TME because of the protonation of the 3-diethylaminopropyl isothiocyanate (DEAP) inner core for celecoxib (CXB) release, while hyaluronic acid@doxorubicine (HA@DOX) prodrug in the outer shell could release by the cleavage of matrix metalloproteinase-2 (MMP-2) peptide. HA@DOX targets tumor cells precisely for triggering ICD. And CXB acts on multiple immune cells to remodulate TME, such as increasing the infiltration of dendritic cells (DCs) and T cells, decreasing the infiltration of the immunosuppressive cells, and eliminating the physical barriers between T cells and tumor cells. For comparison, HA-DOCA/DOX/CXB traditional nanoparticles are constructed. And DOX@HA-MMP-2-DEAP/CXB performs an impressive antitumor effect, which shows potential in enhancing the effect of chemoimmunotherapy.