Macrophage membrane-camouflaged nanoclusters of ultrasmall iron oxide nanoparticles for precision glioma theranostics.

Developing effective nanomedicines to cross the blood-brain barrier (BBB) for efficient glioma theranostics is still considered to be a challenging task. Here, we describe the development of macrophage membrane (MM)-coated nanoclusters (NCs) of ultrasmall iron oxide nanoparticles (USIO NPs) with dual pH- and reactive oxygen species (ROS)-responsivenesses for magnetic resonance (MR) imaging and chemotherapy/chemodynamic therapy (CDT) of orthotopic glioma. Surface citrate-stabilized USIO NPs were solvothermally synthesized, sequentially modified with ethylenediamine and phenylboronic acid, and cross-linked with gossypol to form gossypol-USIO NCs (G-USIO NCs), which were further coated with MMs. The prepared MM-coated G-USIO NCs (G-USIO@MM NCs) with a mean size of 99.9 nm display tumor microenvironment (TME)-responsive gossypol and Fe release to promote intracellular ROS production and glutathione consumption. With the MM-mediated BBB crossing and glioma targeting, the G-USIO@MM NCs can specifically inhibit orthotopic glioma in vivo through the gossypol-mediated chemotherapy and Fe-mediated CDT. Meanwhile, USIO NPs can be dissociated from the NCs under the TME, thus allowing for effective T1-weighted glioma MR imaging. The developed G-USIO@MM NCs with simple components and drug as a crosslinker are promising for glioma theranostics, and may be extended to tackle other cancer types.

Brain Delivery of Biomimetic Phosphorus Dendrimer/Antibody Nanocomplexes for Enhanced Glioma Immunotherapy via Immune Modulation of T Cells and Natural Killer Cells.

Fully mobilizing the activities of multiple immune cells is crucial to achieve the desired tumor immunotherapeutic efficacy yet still remains challenging. Herein, we report a nanomedicine formulation based on phosphorus dendrimer (termed AK128)/programmed cell death protein 1 antibody (aPD1) nanocomplexes (NCs) that are camouflaged with M1-type macrophage cell membranes (M1m) for enhanced immunotherapy of orthotopic glioma. The constructed AK128-aPD1@M1m NCs with a mean particle size of 160.3 nm possess good stability and cytocompatibility. By virtue of the decorated M1m having α4 and ß1 integrins, the NCs are able to penetrate the blood-brain barrier to codeliver both AK128 with intrinsic immunomodulatory activity and aPD1 to the orthotopic glioma with prolonged blood circulation time. We show that the phosphorus dendrimer AK128 can boost natural killer (NK) cell proliferation in peripheral blood mononuclear cells, while the delivered aPD1 enables immune checkpoint blockade (ICB) to restore the cytotoxic T cells and NK cells, thus promoting tumor cell apoptosis and simultaneously decreasing the tumor distribution of regulatory T cells vastly for improved glioma immunotherapy. The developed nanomedicine formulation with a simple composition achieves multiple modulations of immune cells by utilizing the immunomodulatory activity of nanocarrier and antibody-mediated ICB therapy, providing an effective strategy for cancer immunotherapy.