Glypican-3-targeted macrophages delivering drug-loaded exosomes offer efficient cytotherapy in mouse models of solid tumours
Jinhu Liu, Huajun Zhao, Tong Gao, Xinyan Huang, Shujun Liu, Meichen Liu, Weiwei Mu, Shuang Liang, Shunli Fu, Shijun Yuan, Qinglin Yang, Panpan Gu, Nan Li, Qingping Ma, Jie Liu, Xinke Zhang, Na Zhang, Yongjun Liu
Abstract
Cytotherapy is a strategy to deliver modified cells to a diseased tissue, but targeting solid tumours remains challenging. Here we design macrophages, harbouring a surface glypican-3-targeting peptide and carrying a cargo to combat solid tumours. The anchored targeting peptide facilitates tumour cell recognition by the engineered macrophages, thus enhancing specific targeting and phagocytosis of tumour cells expressing glypican-3. These macrophages carry a cargo of the TLR7/TLR8 agonist R848 and INCB024360, a selective indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor, wrapped in C16-ceramide-fused outer membrane vesicles (OMV) of Escherichia coli origin (RILO). The OMVs facilitate internalization through caveolin-mediated endocytosis, and to maintain a suitable nanostructure, C16-ceramide induces membrane invagination and exosome generation, leading to the release of cargo-packed RILOs through exosomes. RILO-loaded macrophages exert therapeutic efficacy in mice bearing H22 hepatocellular carcinomas, which express high levels of glypican-3. Overall, we lay down the proof of principle for a cytotherapeutic strategy to target solid tumours and could complement conventional treatment. Macrophages are considered a good candidate for cancer cytotherapy because of their phagocytotic capacity, enabling them to deliver cargo to tissues. Here authors engineer macrophages that are targeted to glypican-3-expressing tumour cells and equipped with drug-loaded exosomes and show therapeutic efficiency in a mouse model of hepatocellular cancer.