Human Monocytes - CD14, CD16 - Ziegler-Heitbrock


Scanning EM of human blood monocytes
(Picture provided by David Hockley, NIBSC, Potters Bar, UK)

Human Monocytes
In Health and Disease

Monocytes develop from myelo-monocytic stem cells in the bone marrow. They then go into blood, where they circulate for a few days in order to then migrate into tissues. In the tissue they further mature into macrophages. Tissue macrophages are extremely heterogenous dependent on the type of tissue (microglial cells in the brain, alveolar macrophages in the lung, osteoclasts in bone) and on the process (giant cells in granuloma, tumor associated macrophages in malignancy).

Blood monocytes are also heterogenous and here two main subsets have been described in human blood. These are the classical CD14++ monocytes and the nonclassical CD14+CD16++ monocytes. The latter cells are characterised by their high level production of the pro-inflammatory cytokine TNF and by their propensity to preferentially develop into potent dendritic cells. Protocols and literature for human monocyte subsets are given under this page.

Monocytes and macrophages play important roles in the immune defence, inflammation and tissue remodelling and they do so by phagocytosis, antigen processing and presentation and by cytokine production.

Analysis of these processes can be done with primary cells or with model cell lines. Here the cell line Mono Mac 6 is a useful tool, which represents the only mature human monocytic cell line available to date. A little less mature is the companion cell line Mono Mac 1, which has been useful for studies on chemokine function. Protocols and literature for both cell lines can be found under this page.

The site is maintained by Loems Ziegler-Heitbrock and is up-dated regularly to include new protocols and publications.