Immune cells clustered in intestines.

a component of the mucosa-associated lymphoid tissue which works in the immune system to protect the body from invasion in the gut.

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