Editorial: Macrophages in Liver Disease

Macrophages constitute a key component of our immune system and play an important role in immune surveillance. Hepatic macrophages are a heterogeneous population of immune cells that mainly comprises of embryonically-derived resident Kupffer cells (KCs), and circulating monocyte-derived macrophages (MoMFs). They play a critical role in disease initiation and progression as well as contribute to disease resolution. Traditionally, macrophages were defined by two broad subsets: classically-activated pro-inflammatory M1 or alternatively-activated anti-inflammatory M2 macrophages. However, it has been recognized that macrophages can differentiate into multiple phenotypes with distinct functions based on the tissue microenvironment.