16
edits
Changes
→Monocytosis
* Lipophage
* Lipophage
* [[Bones - Anatomy & Physiology#Osteoclasts|Osteoclasts]] in bone
* [[Bones - Anatomy & Physiology#Osteoclasts|Osteoclasts]] in bone
* [[Neurons_-_Anatomy_%26_Physiology#Microglial_Cells|Microglial cell]] in bone & brain
* [[Neurons_- Anatomy & Physiology#Microglial_Cells|Microglial cell]] in bone & brain
* Specialised histiocytes
* Specialised histiocytes
** Epithelioid cell
** Epithelioid cell
<p>Monocytes can live for months to years in the circulation.</p>
<p>Monocytes can live for months to years in the circulation.</p>
<p>Monocytes are referred to as macrophages once they enter a tissue by '''diapedesis'''.</p>
<p>Monocytes are referred to as macrophages once they enter a tissue by '''diapedesis'''.</p>
<p>Monocytes/macrophages act as phagocytes, removing particular antigens. They also act as antigen presenting cells to take up, process and present antigen to [[Lymphocytes#T cells|T cells]].</p>
<p>Monocytes/macrophages act as phagocytes, removing particular antigens. They also act as antigen presenting cells to take up, process and present antigen to [[T cells]].</p>
===In pathology===
==Monocytosis==
An increase in the number of monocytes (haematogenous macrophages) in the blood is known as a [[Monocytosis|monocytosis]]. It occurs in conjunction with other changes inidicative of a [[Stress Leucogram|stress leucogram]] or it may occur independently. Monocytes in the blood represent a brief transitional stage as they quickly move into tissues and differentiate further to tissue macrophages; they rarely perform any notable functions whilst in the bloodstream but they have been found to phagocytose red blood cells in cases of immune-mediated haemolytic anaemia. The major causes of monocytosis are:
*Stress leucogram mediated by the production or administration of glucocorticoids (plus a neutrophilia, eosinopenia and lymphopenia).
*Chronic inflammatory processes, including chronic bacterial infections and chronic inflammatory diseases of the liver (chronic hepatitis and cholangitis) and pancreas (chronic pancreatitis).
*Granulomatous disease results in monocytosis as monocytes are recruited to contain certain types of bacteria (namely Mycobacteria spp., Nocardia spp., Actinomyces and Rhodococcus equi) or foreign bodies.
*Certain types of monocytic or myelomonocytic chronic myeloid leukaemia may result in the presence of large numbers of monocytes in the blood.
[[Category:Blood_Cells]]
[[Category:Blood_Cells]] [[Category:Kate English reviewing]]