4. The Gut & Immunity

Immune cells present within the gut represent 70-80% of total immune cells in the body. It is therefore relevant to explore the gut and its role in immunity in detail. Immunity within the gut expresses all three levels of defence; physical barriers, innate and adaptive immunity. The mucosal lining of the gut covers 200-300 m² and consists of a single mucous epithelial layer together with the lamina propria containing immune cells.