Description: Scheme electron microscopy.
The diameter of monocytes ranges from 12-20 µm. Characteristic is the large (kidney-shaped) nucleus with one or more nucleoli (1) and several indentations. The cytoplasm contains:
(2): Golgi areas,
(3): Electron-dense lysosomal granules or primary or azurophilic granules with acid phosphatase, arylsulfatase;
(4): Phagosomes (vacuoles)
(6): Small pseudopodia reflect the ameboid movement and phagocytic ability.
Background: Monocytes derive from monoblasts in the bone marrow, circulate in the bloodstream for 8-24 hours, and then migrate into tissues, and can remain active for months and probably years. The cells can either differentiate into tissue macrophages or into antigen-presenting cells (APC´s). They can also be active in antibody-dependent cell-mediated cytoxicity reactions (ADCC). Depending on their activity and differention status these cells display receptors for complement factors, antibodies and chemotactic factors. They can also generate several interleukins.
Keywords/Mesh: blood, bone marrow, monocyte, lysosome, phagocytosis, histology, electron microscopy, POJA collection