%0 Journal Article %T The Mononuclear Phagocyte System: The Relationship between Monocytes and Macrophages %J - %D 2019 %R https://doi.org/10.1016/j.it.2018.11.007 %X Macrophages arise during embryonic development in three waves %U https://www.cell.com/trends/immunology/fulltext/S1471-4906(18)30226-6