Macrophage Membrane-Camouflaged Responsive Polymer Nanogels Enable Magnetic Resonance Imaging-Guided Chemotherapy/Chemodynamic Therapy of Orthotopic Glioma

Chemodynamic therapy (CDT) utilizes iron-initiated Fenton chemistry to destroy tumor cells by converting endogenous H2 O2 into the highly toxic hydroxyl radical (. OH). There is a paucity of Fenton-like metal-based CDT agents. Intracellular glutathione (GSH) with . OH scavenging ability greatly reduces CDT efficacy. A self-reinforcing CDT nanoagent based on MnO2 is reported that has both Fenton-like Mn2+ delivery and GSH depletion properties. In the presence of HCO3- , which is abundant in the physiological medium, Mn2+ exerts Fenton-like activity to generate . OH from H2 O2 . Upon uptake of MnO2 -coated mesoporous silica nanoparticles (MS@MnO2 NPs) by cancer cells, the MnO2 shell undergoes a redox reaction with GSH to form glutathione disulfide and Mn2+ , resulting in GSH depletion-enhanced CDT. This, together with the GSH-activated MRI contrast effect and dissociation of MnO2 , allows MS@MnO2 NPs to achieve MRI-monitored chemo-chemodynamic combination therapy.

Neutrophils carrying drug-containing liposomes can suppress recurrence of brain tumours after surgical removal of the tumour.

Cancer metastasis leads to high mortality of breast cancer and is difficult to treat because of the poor delivery efficiency of drugs. Herein, we report the wrapping of a drug-carrying liposome with an isolated macrophage membrane to improve delivery to metastatic sites. The macrophage membrane decoration increased cellular uptake of the emtansine liposome in metastatic 4T1 breast cancer cells and had inhibitory effects on cell viability. In vivo, the macrophage membrane enabled the liposome to target metastatic cells and produced a notable inhibitory effect on lung metastasis of breast cancer. Our results provide a biomimetic strategy via the biological properties of macrophages to enhance the medical performance of a nanoparticle in vivo for treating cancer metastasis.