Immunomodulatory Magnetic Microspheres for Augmenting Tumor-Specific Infiltration of Natural Killer (NK) Cells

The purpose of this research is to develop magnetic resonance imaging (MRI) visible immunomodulatory microspheres (IMM-MS) for efficient image guided cancer immunotherapy. 1MM-MS composed of recombinant interferon gamma (IFN-gamma), iron oxide nanocubes (IONC), and biodegradable poly(lactide-co-glycolide) (PLGA) were successfully prepared via a double-emulsion method. The prepared 1MM-MS exhibited a sustained IFN-gamma release and highly sensitive MR T-2 contrast effects. Finally, in an orthotopic liver tumor VX2 rabbit model, successful hepatic intra-arterial (IA) transcatheter delivery of IMM-MS to liver tumors was confirmed with MR images. The deposition Of EVIM-MS significantly increased NK-cell infiltration into the liver tumor site.