Paneth cell | |
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Paneth cells
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Details | |
Identifiers | |
Latin | cellula panethensis |
MeSH | Paneth+Cells |
Code | TH H3.04.03.0.00017 |
Anatomical terminology
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Paneth cells, along with goblet cells, enterocytes, and enteroendocrine cells, represent the principal cell types of the epithelium of the small intestine. (A few may also be found sporadically in the cecum and appendix.) They are identified microscopically by their location just below the intestinal stem cells in the intestinal glands (crypts of Lieberkühn) and the large eosinophilic refractile granules that occupy most of their cytoplasm. These granules consist of several anti-microbial compounds and other compounds that are known to be important in immunity and host-defense. When exposed to bacteria or bacterial antigens, Paneth cells secrete some of these compounds into the lumen of the intestinal gland, thereby contributing to maintenance of the gastrointestinal barrier.
Paneth cells are named after Joseph Paneth (1857–1890), an Austrian physiologist.
Paneth cells are found throughout the small intestine and the appendix at the base of the intestinal glands. The Paneth cell numbers demonstrate an ascending trend with highest numbers towards the distal end of the small intestine. Like the other epithelial cell lineages in the small intestine, paneth cells originate at the stem cell region near the bottom of the gland. However, unlike the other epithelial cell types, paneth cells migrate downward from the stem cell region and settle just adjacent to it. This close relationship to the stem cell region is thought to suggest that Paneth cells are important in defending the gland stem cells from microbial damage, although their function is not entirely known. Furthermore, among the four aforementioned intestinal cell lineages, the Paneth cells live the longest (18–23 days).
"These cells synthesize and secrete substantial quantities of antimicrobial peptides and proteins. More recent studies have determined that these antimicrobial molecules are key mediators of host-microbe interactions, including homeostatic balance with colonizing microbiota and innate immune protection from enteric pathogens. Perhaps more intriguing, Paneth cells secrete factors that help sustain and modulate the epithelial stem and progenitor cells that cohabitate in the crypts and rejuvenate the small intestinal epithelium. "