Corpus: Lingual tonsil

The lingual tonsil is a secondary lymphatic organ located at the base of the tongue near the terminal sulcus. It forms an integral part of the mucosa-associated lymphoid tissue (MALT).

The lingual tonsil comprises lymphatic tissue enriched with numerous lymph follicles and is a component of Waldeyer's pharyngeal ring. Unlike the pharyngeal tonsil, it is unpaired. The lingual tonsil is encased by lingual muscles and features less prominent crypts compared to the palatine tonsil. Its surface is coated with a multi-layered, non-keratinized squamous epithelium. The crypts terminate in crater-like indentations on small mucosal elevations, known as papillae lenticulares (alternatively referred to as lentiform papillae). Additionally, mucous glands are present within the mucosa.

The lingual tonsil plays a vital role in the immune system by serving as a barrier against infections. It actively defends against pathogens entering the throat through the oral mucosa.