Monocytes typically circulate through the blood for 1–3 days before migrating into tissues, where they become macrophages or dendritic cells. Macrophages are monocytes that have migrated from the bloodstream into any tissue in the body.

How does monocyte become a macrophage?

Macrophages are formed through the differentiation of monocytes, one of the major groups of white blood cells of the immune system. When there is tissue damage or infection, the monocytes leave the bloodstream and enter the affected tissue or organ and undergo a series of changes to become macrophages.

What causes monocytes to differentiate into macrophages?

Monocytes can differentiate into inflammatory or anti-inflammatory subsets. Upon tissue damage or infection, monocytes are rapidly recruited to the tissue, where they can differentiate into tissue macrophages or dendritic cells.