Tumor Cell Membrane Biomimetic Mesoporous Silicon Materials in Combination with PD-L1 Knockout Achieved through the CRISPR/Cas9 System for Targeted and Immunotherapeutic Purposes

Nanoparticle-based drug delivery systems, which enable the effective and targeted delivery of chemotherapeutic drugs to tumors, have revolutionized cancer therapy. Mesoporous silicon materials (MSN) have emerged as promising candidates for drug delivery due to their unique properties. The therapeutic efficacy can be significantly enhanced when treatments exhibit both targeting and antiphagocytic properties. In this study, cell membranes extracted from B16-F10 cells were used to encapsulate carboplatin (CBP)-loaded MSN via physical extrusion. Additionally, we intratumorally injected a plasmid containing the CRISPR/Cas9 system to achieve PD-L1 knockout, thereby reactivating the immune system. The cell membrane coating endowed the CBP@MSN with excellent slow-release capability and cytocompatibility. Enhanced tumor cell uptake of CBP@MSN@M was observed due to homologous targeting by cancer cell membranes. Moreover, CBP@MSN@M demonstrated enhanced antitumor efficacy in vivo and promoted the proliferation of immune cells. Finally, the antitumor effect was further improved by the knockout of PD-L1 within the tumor microenvironment. These results suggest that the newly prepared CBP@MSN@M, combined with PD-L1 knockout, holds significant potential as an effective therapeutic approach for treating tumors.