Peyer's plaques
The Peyer's plaques , also called Peyer's glands, clusters or plates ( Folliculi lymphatici aggregati ), are connected collections of 10 to 50 lymph follicles . They occur throughout the small intestine, but they are most commonly found in the ileum and appendix . They are visible from the outside through the intestinal wall as structures about 1 cm in size. They are named after the Swiss anatomist Johann Conrad Peyer (1653–1712).
function
Peyer's plaques belong to the lymphatic system , are part of the so-called MALT system ( mucosa associated lymphoid tissue , English for “mucosa-associated lymphoid tissue”) or, more specifically, of the GALT ( well associated lymphoid tissue , English for “gut-associated lymphatic tissue”) Tissue ") and, as a collection of cells of the special, acquired immune system, play an important role in the defense against infection in the intestine and in the dissemination of immunological information.
Tissue structure / histology
Peyer's patches are usually compared to the Gekröseansatz (mesentery) in the submucosa and the lamina propria of the mucosa (tunica mucosa). Where the follicles protrude into the mucosa, the usual villi and crypts are missing. So-called M cells are found at these dome-like protruding points into the lumen, which are therefore also referred to as domes . For example, they pass viruses and bacteria through their cell bodies to the follicles (transcytosis) and thus trigger an immune response.
In ruminants , Peyer's plaques are evidently the bursa-equivalent organ .
literature
- Ernst Mutschler : Human anatomy, physiology, pathophysiology. , 5th ed. Pp. 148, 358.
- HistoWeb of the Anatomical Institute Tübingen
Individual evidence
- ↑ Walther Graumann: Compact Textbook Anatomy 3 . Schattauer Verlag 2004, ISBN 978-3-7945-2063-3 , p. 106.
- ↑ Uwe Gille: Cardiovascular and immune system, Angiologia . In: Franz-Viktor Salomon et al. (Hrsg.): Anatomie für die Tiermedizin . Enke-Verlag Stuttgart, 2nd edition 2008, pp. 404–463. ISBN 978-3-8304-1075-1