Leukocytes arise from hemopoietic stem cells in the bone marrow. Leukocytes are involved in pathogen recognition, phagocytosis (ingestion of particles), pathogen destruction, inflammation mediation, and antigen presentation. Granulocytes include neutrophils, basophils, eosinophils, and mast cells.

Where do leukocytes get made?

White blood cells are made in the bone marrow. They are stored in your blood and lymph tissues. Because some white blood cells called neutrophils have a short life less than a day, your bone marrow is always making them.

What stimulates leukocyte production?

Leukocyte-promoting factors include colony stimulating factors (CSFs) (produced by monocytes and T lymphocytes), interleukins (produced by monocytes, macrophages, and endothelial cells), prostaglandins, and lactoferrin.