mucosa-associated lymphoid tissue


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Related to mucosa-associated lymphoid tissue: cell-mediated immunity

mucosa-associated lymphoid tissue (MALT),

a class of lymphoid tissue comprising nodular aggregates found in association with the wet mucosal surfaces of the body such as those of the respiratory, digestive, and urinary systems.

MALT

Mucosa-associated lymphoid tissue. An umbrella term for extranodal aggregates of lymphoid tissue in the bronchus (BALT), gut (GALT) and skin (SALT), as well as breast and uterine cervix. MALT is the arm of the immune defence in closest contact with exogenous antigens, thus differing from the compartmentalised peripheral somatic lymphoid tissues, which include the lymph nodes, thymus and spleen. Dimeric IgA or “secretory” IgA appears to be under MALT’s control, and MALT may be the sites of origin of extranodal lymphomas.

mu·co·sa-as·so·ci·a·ted lym·phoid tis·sue

(MALT) (myū-kō'să-ă-sō'sē-ā-tĕd lim'foyd tish'ū)
A class of lymphoid tissue comprising nodular aggregates found in association with the wet mucosal surfaces of the body such as those of the respiratory, digestive, and urinary systems.

mucosa-associated lymphoid tissue

Abbreviation: MALT
Aggregates of T and B lymphocytes found in all mucous membranes, a line of defense against infection. Examples include Peyer's patches in the small intestine and lymph nodules in the colon, trachea, and bronchi. MALT contains CD4+ and CD8+ T cells and activated B cells and may occasionally undergo malignant transformation into lymphomas.
See: mucosal immune system
See also: tissue
References in periodicals archive ?
10) Mucosa-associated lymphoid tissue in the lung was first described in 1973, (11) and is believed to be acquired as secondary long-term response to various antigenic stimuli such as smoking, immunologic disease such as Sjogren syndrome, rheumatoid arthritis, Hashimoto thyroiditis, systemic lupus erythematosus, or infections such as hepatitis C and human immunodeficiency virus (HIV).
Mucosa-associated lymphoid tissue is located in the respiratory and urogenital tracts, but mostly in the gastrointestinal tract, presenting one of the largest exchange surfaces in the body.
Secondary Sjogren's syndrome in association with autoimmune diseases has a greater incidence of mucosa-associated lymphoid tissue or mucosa-associated lymphoid tissue lymphoma with a predilection for the parotid gland.
Indications carried forward from the prior edition included peptic ulcer disease, nonulcer dyspepsia, mucosa-associated lymphoid tissue (MALT) lymphoma, atrophic gastritis, a history of gastric cancer resection, first-degree relatives of patients with gastric cancer, and patients who, on consulting with a physician, want to be tested.
More recognized is the relationship between gastric mucosa-associated lymphoid tissue (MALT) lymphomas, which are similar to primary cutaneous B-cell lymphomas in the skin, and Helicobacter pylori infections.
To the Editor: Helicobacterpylori infection is a principal cause of chronic active gastritis and peptic ulcer disease as well as gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma (1).
pylori-associated diseases can be diagnosed reliably only by invasive means--endoscopy with biopsies-that can identify intestinal metaplasia, mucosa-associated lymphoid tissue (MALT) lymphoma, peptic ulcer disease, and other problems.
Its efficacy analysis included 63 patients with three sub-types of MZL: mucosa-associated lymphoid tissue (MALT; N=32), nodal and splenic.
pylori is involved in the development of several gastroduodenal diseases, including gastritis, peptic ulcer disease, gastric adenocarcinoma and gastric mucosa-associated lymphoid tissue lymphoma and its eradication could change the natural history of some of these.
sup][1] More recently, IgG4-positve mucosa-associated lymphoid tissue (MALT) lymphomas have been described in ocular, thyroid, dura, and other tissues.