Description

The lymphoid elements of the gut comprise organised lymphoid tissues such as the Peyer’s patches, and the mesenteric lymph nodes. The effector sites of the intestine are the mucosal epithelium and underlying lamina propria. Here there are many different immune cells, including activated T cells, regulatory T cells, B cells, plasma cells, mast cells, dendritic cells and macrophages, even under normal conditions. That this does not result in overt tissue pathology reflects the fact that the effector cells present, are actively held in check by potent regulatory mechanisms. Think microbiota and ILC’s.