Question

MALT constitutes about _____ percent of the lymphoid tissue in the human tissue.
A. 10 %
B. 50 %
C. 20 %
D. 70 %

Answer 1

MALT stands for mucosa-associated lymphoid tissue. It is made up of T cells, B cells and macrophages. It is found in association with mucosal tissue.

Complete Answer:
- The lymphoid tissues are the cells and tissues involved with the lymphatic system. Bone marrow and thymus are primary lymphoid tissues and lymphocyte development sites. Lymph nodes, spleen, tonsils and Peyer's patches are examples of secondary lymphoid tissue. Lymphoid tissue has a variety of distinct structural organisations related to its specific function in the immune response.
- Mucosa-associated tissues (MALT) are lymphoid tissues related with mucosal surfaces of almost any organ, but particularly those of the digestive, genitourinary and respiratory tract, which are continuously exposed to a wide range of potentially harmful microorganisms and thus need their own antigen capture and lymphocyte presentation system.
- The mucosal lymphoid tissues, while present at different locations, contain the same essential compartments – follicles, interfollicular regions, follicle-associated epithelium and subepithelial dome regions. The mucosa-associated lymphoid tissue activates immune responses to particular antigens present on all mucosal surfaces.
- The inductive sites of MALT are secondary immune tissues where antigen sampling happens and immune responses are initiated. The bulk (> 50 per cent) of lymphoid tissue in the human body is found within the respiratory, digestive and genitourinary tract.

Thus, the correct answer is option B i.e 50 %.

Note: Based on their position, the MALT can be subdivided into Nasal-associated lymphoid tissue (NALT), Bronchus-associated lymphoid tissue (BALT), Gut-associated lymphoid tissue (GALT), and lymphoid tissue associated with the genitourinary system.