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Oncolytic viruses hold great promise for cancer treatment but their practical applications are seriously impaired by a series of limitations. Herein, an engineered oncolytic adenovirus (OA) is constructed that can boost both the direct oncolysis and antitumor immune response of OA attributed to the increased tumor targeting and low‐pH responsive fusogenic activity. The tumor cell membranes are decorated with vesicular stomatitis virus glycoprotein (VSVG) via vesicular stomatitis virus (VSV) infection and then used to mask OA (V‐M@OA). After systemic administration, the engineered OA can target homologous tumors owing to the homing ability of tumor membranes. Then the unique low‐pH responsive fusogenic activity of VSVG significantly enhances the replication of OA by promoting the whole virus infection process, resulting in remarkable virus‐mediated tumoricidal effects and thus abundant in situ released tumor‐associated antigens (TAAs). Meanwhile, VSVG on V‐M@OA augments the adjuvanticity of OA and thus significantly enhancing the antitumor immune response. The synergism of virus‐mediated killing and immune effects leads to significant tumor inhibition with no obvious side effects. [ABSTRACT FROM AUTHOR]

Exosomes hold great potential in therapeutic development. However, native exosomes usually induce insufficient effects in vivo and simply act as drug delivery vehicles. Herein, we synthesize responsive exosome nano‐bioconjugates for cancer therapy. Azide‐modified exosomes derived from M1 macrophages are conjugated with dibenzocyclooctyne‐modified antibodies of CD47 and SIRPα (aCD47 and aSIRPα) through pH‐sensitive linkers. After systemic administration, the nano‐bioconjugates can actively target tumors through the specific recognition between aCD47 and CD47 on the tumor cell surface. In the acidic tumor microenvironment, the benzoic‐imine bonds of the nano‐bioconjugates are cleaved to release aSIRPα and aCD47 that can, respectively, block SIRPα on macrophages and CD47, leading to abolished "don't eat me" signaling and improved phagocytosis of macrophages. Meanwhile, the native M1 exosomes effectively reprogram the macrophages from pro‐tumoral M2 to anti‐tumoral M1. [ABSTRACT FROM AUTHOR]