Langerhans, Paul

Antigen-presenting cells are also called dendritic cells because of their long branched processes on dendrites. They were discovered as early as 1868 by Paul Langerhans, after whom they are sometimes named. It was 100 years later diat it was appreciated diat diey had a role in the immune system. 

Islets of Langerhans are clusters of endocrine cells in the pancreas. One distinguishes the gjucagon-secreting A cells, the insulin-secteting B cells and the somatostatin-secreting D cells. (Named after Paul Langerhans who first described such clusters of ceUs as a medical student in 1869). 

In 1968, Paul Langerhans discovered the presence of a particular type of epidermal cell in humans, which is now named after him. The Langerhans cell (LC) is a mobile dendritic cell that has no desmosomes and is found in most multilayered malpighian epithelia. LCs make up 2-5% of epidermal cells. They come from the medulla and migrate towards and within the skin and stay within the epidermis for 2 weeks at the most. 

Islats of Langarhans Smallgroupsof cells In the pancreas that function as an endocrine gland. The alpha (or A) cells secrete the hormone glucagon, the beta (or B) cells secrete Insulin, and the D cells secrete somatostatin. The Islets are named after their discoverer, the German anatomist and mi-croscopist Paul Langerhans (1847-88). 

Langerhans, P. Uber die Nerven der menschUchen Haul. Virchows Arch Pathol. 1868 44 325-37. In this paper, entitled On the nerves of the human skin , Paul Langerhans reported for the first time the presence of large cells with long dendrites in the epidermis of human skin. 

A spherical islet of Langerhans from the pancreas of a mouse, situated next to a blood vessel. It has been stained to visualize the insulin, which is found in the central spherical region (Taken from Paul Langerhans... 

Paul Langerhans - http //commons.wikimedia.0rg/wiki/File Paul Langerhans.jpg... 

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