Scheme 1.

Schematic illustration of the synthesis and antitumor mechanism of the MnDIG@PEG nanocomposite. Here, the large‐pore organosilica mesoporous‐silica decorated Mn₃O₄ nanoparticles as the cornerstone are prepared first. Then by loading IDOi, GOx, and modifying the DSPE‐PEG. After injecting the obtained MnDIG@PEG nanocomposite into tumor bearing BALB/c mice, the nanocomposites can rapidly decompose in the endogenous TME, release Mn²⁺, GOx, and IDOi. The self‐amplification chemodynamic/starvation therapy can enhance immunogenic cell death, while IDOi inhibit the IDO activity. Taking advantage of enhanced immune response by Mn²⁺/GOx‐mediated chemodynamic/starvation therapy and immune suppression performed by IDO blockade immunotherapy, the MnDIG@PEG nanocomposite can achieve a conspicuous therapeutic effect.