A macrophage membrane-coated mesoporous silica nanoplatform inhibiting adenosine A2AR via in situ oxygen supply for immunotherapy.

Immunotherapy has achieved remarkable research outcomes and shows the potential to cure cancer. However, its therapeutic response is limited in terms of the immunosuppressive tumor microenvironment induced by hypoxia, in which the adenosinergic A2A receptor (A2AR) pathway is mainly participated. Here, we developed a novel core/shell structured nanoplatform composed of macrophage membrane-coated mesoporous silica nanoparticles which loaded catalase, doxorubicin (Dox), and resiquimod (R848), to promote the efficacy of immunotherapy. The nanoplatform is able to actively target the tumor site via ligand binding, and the A2AR of T regulatory (Treg) cells can further be blocked due to in situ oxygen production by hydrogen peroxide catalysis. Meanwhile, Dox and R848 released from the nanoplatform can induce immunogenic cell death and enhance the activation of dendritic cells (DCs), respectively. Thus, the improved microenvironment by A2AR blockade and the stimulation of the DCs to enhance the CD8+ T cells mediated immune response were achieved. Consequently, the expression of Treg cells decreased to 9.79% in tumor tissue and the inhibition rate of tumor growth reached 73.58%. Therefore, this nanoplatform provides a potential strategy for clinical application in cancer immunotherapy.