Microorganisms and Disease
Type III secretion systems are used to inject "effector" proteins directly into a host cell. Salmonella uses a type III secretion system to help the pathogen to
survive within macrophages
secrete LT (heat labile toxin) and ST (heat stable toxin) into the lumen of the intestine
survive the acid pH of the stomach
activate T cells to proliferate and secrete cytokines