Peyer’s patches
Small, nodular clusters of lymphoid tissue scattered throughout the mucous membrane lining of the SMALL INTESTINE. Though not encapsulated as are LYMPH NODES, Peyer’s patches are more distinct and organized than other MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT). Peyer’s patches are elements of GUT-ASSOCIATED LYMPHOID TISSUE (GALT), a subset of MALT. GALT lies beneath the epithelial tissue (mucosal lining) of the gastrointestinal tract. Peyer’s patches contain concentrations of B-cell lymphocytes that actively produce antibodies. They also contain some T-cell lymphocytes and phagocytic cells to enhance the IMMUNE RESPONSE in the small intestine.
For further discussion of Peyer’s patches within the context of the structures and functions of the immune system, please see the overview section “The Immune System and Allergies.”
See also ANTIBODY; B-CELL LYMPHOCYTE; LYMPHOCYTE; PHAGOCYTE; T-CELL LYMPHOCYTE.