Reticuloendothelial system

Reticuloendothelial system (RES), also known as the mononuclear phagocyte system or macrophage system, is a part of the immune system that consists of the phagocytic cells located in reticular connective tissue. The cells are primarily monocytes and macrophages, and they accumulate in lymph nodes and the spleen. The Kupffer cells of the liver and tissue histiocytes are also part of the RES.

Function

The primary function of the reticuloendothelial system is the removal of worn-out red blood cells, also known as erythrocytes, from circulation. This process is known as erythrocytosis. The RES also plays a crucial role in the immune response, as it is responsible for the removal of foreign substances from the blood.

Components

The reticuloendothelial system is made up of several components, including:

• Monocytes: These are a type of white blood cell that can become macrophages.
• Macrophages: These cells are responsible for detecting, engulfing and destroying pathogens and apoptotic cells.
• Kupffer cells: These are specialized macrophages located in the liver, responsible for the removal of harmful substances from the blood.
• Tissue histiocytes: These are found in many organs and tissues, where they ingest harmful foreign particles and bacteria.

Clinical significance

Diseases and conditions that affect the reticuloendothelial system can have serious implications for health. These include:

• Histiocytosis: This is a group of diseases that occur when there is an over-production of cells that are part of the RES.
• Hemophagocytic lymphohistiocytosis: This is a condition in which the body makes too many activated macrophages.
• Gaucher's disease: This is a genetic disorder that affects the body's ability to break down fats that can accumulate in the liver and spleen.

See also

• Mononuclear phagocyte system
• Immune system
• Macrophage
• Kupffer cells
• Histiocytes