Scheme 1.

Construction of a self-amplified biomimetic nanosystem to induce ICD and activate an immune microenvironment for boosting the therapeutic effect of anti-PD-L1 antibody. A) Schematic illustration of the process to prepare mEHGZ nanoparticles by encapsulating EPI, Gox and hemin in ZIF-8 nanoparticles and coating the nanoparticles with the CRT over-expressed tumor cell membrane. B) After endocytosis of mEHGZ nanoparticles into cells, the released EPI from mEHGZ in response to a low pH kills tumor cells in an immunogenic way. Gox and hemin mediate a cascade reaction for generation of hydroxyl free radical (·OH) and depletion of intracellular GSH to exert strong stress on the ER, strengthening the ICD effect. C) The released antigens and DAMPs after ICD promote DCs maturation, CD8⁺ T cells infiltration and cytokines secretion to create an immunosupportive microenvironment to boost the therapeutic effect of anti-PD-L1 antibody.