Exploring Chitosan-Shelled Nanobubbles to Improve HER2+ Immunotherapy Through Dendritic Cells Targeting

Immunotherapy is a valuable approach for the treatment of cancer. Nanotechnology-based delivery systems emerged as a powerful tool for improving immunotherapeutics. Therefore, their association have been proposed to overcome some biopharmaceutical limitations of immunotherapy. This work aims at designing a novel immunotherapeutic nanoplatform for the treatment of HER2+ breast cancer. Here, purposely-tailored chitosan-shelled nanobubbles (NBs) were developed for the loading of DNA vaccine. The NBs were then functionalized with anti-CD1a antibody to target dendritic cells (DCs). The NB formulations showed sizes of about 300 nm and a good physical stability up to 6 months stored at 4 °C. The in vitro characterization confirmed that these NBs were able to load DNA with a good encapsulation efficiency (82%). The antiCD1a-functionalized NBs targeted to DCs demonstrated the capability to induce activation of DCs both in human and mouse models, and elicit a specific immune response able to delay tumor growth in vivo in mice. The results are the proof of concept that DC-targeted chitosan nanobubbles loaded with tumor vaccine may provide an attractive nanotechnology approach for the future immunotherapeutic treatment of cancer.