Mucin is not secreted by

Paneth cells are a specific type of cell within the crypts of Lieberkuhn. These cells have atypically oriented bright eosinophilic granules containing a variety of antimicrobial proteins and play a role in mucosal immunity (and not mucin secretion) Brunner's glands: are sub-mucosal mucus gland within the duodenum. Goblet cells: are mucin-secreting cells. Crypts of Lieberkuhn: are lined by goblet cells besides other cell types. These are thus also involved in mucin secretion.