M1 macrophage-derived nanovesicles repolarize M2 macrophages for cancer treatment

Abstract

Cancer immunotherapy is a treatment that activate immune cells to induce anti-tumor immune response. Since macrophages are common immune cells in tumor microenvironment (TME), tumor-associated macrophages (TAM) are studied as a attractive target for cancer immunotherapy. Macrophages are known to have two different phenotypes

M2 macrophages release anti-inflammatory cytokines and angiogenesis factor that potentiate tumor growth. M1 macrophages release pro-inflammatory cytokines and induce anti-tumor immune response. Cancer cells release cytokines that affect TAM to polariae to M2 macrophages. Thus, repolarazation of M2 TAM to M1 macrophages may be promising immunotherapy.

Exosomes are known as nanocarrier that can induce phenotype change in recipient cells. In this study, we used exosome-like nanovesicles derived from M1 macrophages (M1NV) to repolarize M2 macrophages to M1 macrophages. M1NV treatment to M2 macrophage showed successful upregulation of M1 marker mRNA expression, protein expression, and cytokines expression in M2 macrophages. Thus, our study indicates M1NV treatment repolarize M2 TAM to M1 macrophages for cancer immunotherapy.