Mucosa-associated lymphoid tissue

The mucosa-associated lymphoid tissue (MALT) (also called mucosa-associated lymphatic tissue) is the diffuse system of small concentrations of lymphoid tissue found in various sites of the body such as the gastrointestinal tract, thyroid, breast, lung, salivary glands, eye, and skin.

Populated by T cells, which are well-situated to encounter antigens that enter through the intestinal mucous epithelium. Contain B cells, plasma cells, activated TH cells and macrophages in loose clusters.

Components
The components of MALT are sometimes subdivided into the following:
 * GALT (gut-associated lymphoid tissue. Peyer's patches are a component of GALT found in the lining of the small intestines.)
 * BALT (bronchus-associated lymphoid tissue)
 * NALT (nose-associated lymphoid tissue)
 * LALT (larynx-associated lymphoid tissue)
 * SALT (skin-associated lymphoid tissue)
 * VALT (vascular-associated lymphoid tissue. A newly recognized entity that exists inside arteries; its role in the immune response is unknown. )
 * CALT (conjunctiva-associated lymphoid tissue in the human eye)

Role in disease
MALT plays a role in regulating mucosal immunity. It may be the site of lymphoma, usually non-Hodgkin lymphoma. A specific entity is the MALT lymphoma linked to Helicobacter pylori in the stomach.