Significance
A multifunctional delivery system (SPIO NP@M) was constructed for effectively delivering therapeutic peptides into the tumor microenvironment for cancer diagnosis and therapy. In this paper, the TPP-1 peptide inhibiting the binding of PD-L1 and PD-1 was delivered and released into the tumor microenvironment by the homotypic targeting of H460 cell membrane and specific digestion by the MMP2 enzyme. SPIO NPs in this system were aggregated effectively at the tumor sites and were used for magnetic resonance imaging of tumors. The SPIO NP@M-P delivery system could effectively extend the half-life of the TPP-1 peptide (60 times longer than that of the free peptide) and could maintain the ability to re-activate T cells and inhibit tumor growth in vitro and in vivo. In conclusion, the SPIO NP@M system coated with lung cancer cell membrane and loaded with the PD-L1-blocking TPP-1 peptide could be a promising integrated platform for tumor diagnosis and treatment.
Statement of significance
A multifunctional delivery system (SPIO NP@M) was constructed for effectively delivering therapeutic peptides into the tumor microenvironment for cancer diagnosis and therapy. In this paper, the TPP-1 peptide inhibiting the binding of PD-L1 and PD-1 was delivered and released into the tumor microenvironment by the homotypic targeting of H460 cell membrane and specific digestion by the MMP2 enzyme. SPIO NPs in this system were aggregated effectively at the tumor sites and were used for magnetic resonance imaging of tumors. The SPIO NP@M-P delivery system could effectively extend the half-life of the TPP-1 peptide (60 times longer than that of the free peptide) and could maintain the ability to re-activate T cells and inhibit tumor growth in vitro and in vivo. In conclusion, the SPIO NP@M system coated with lung cancer cell membrane and loaded with the PD-L1-blocking TPP-1 peptide could be a promising integrated platform for tumor diagnosis and treatment.