 Macrophages play a critical role in the maintenance of immune homeostasis and are involved in the development of many autoimmune diseases. Recent studies have shown that macrophages can be polarized into two distinct phenotypes, M1 and M2, which are characterized by different gene expression profiles and functional activities. These polarized macrophages can be used to treat autoimmune diseases through targeted therapies. This article was authored by Yuan Peng, Meng Jianjiu, Hong Yang, and others.