Feasibility study of dual-targeting paclitaxel-loaded magnetic liposomes using electromagnetic actuation and macrophages

This work aims to develop a novel electromagnetic and macrophage-mediated drug delivery system to transport anticancer drug (Paclitaxel, PTX)-encapsulated magnetic liposomes (PTX-MLPs) to tumors. The PTX-MLPs are engulfed into macrophages by phagocytosis of murine macrophages (J774A1). Therefore, the macrophages with PTX-MLPs can be dually targeted both by an external electromagnetic field and by chemotaxis of the macrophages to the tumors. Under the electromagnetic field, a single macrophage with PTX-MLPs can be controlled following predefined paths and can reach an average velocity of 10.48 +/- 4.43 mu m/s. Meanwhile, using chemotaxis, the macrophages with PTX-MLPs can infiltrate through a 5 m pore membrane to chemo-attractants in transwell migration assays, with infiltration rate of up to 73.70 +/- 4.63%. In addition, their therapeutic efficacy is investigated using an in-vitro cytotoxicity assay on breast cancer (4T1) and colorectal cancer (CT26) models. The results confirm that the macrophages with PTX-MLPs can carry a sufficient amount of drug to kill the cancer cells with the IC50 values for the 4T1 and CT26 cells of 52.97 +/- 1.06 mu g/mL and 117.04 +/- 1.82 mu g/mL, respectively. The outcomes of this study suggest that a potential active cancer therapy can be developed through the dual targeting system using macrophages with PTX-MLPs and magnetic actuation. (C) 2016 Elsevier B.V. All rights reserved.