Salmonella is a genus of bacteria that causes gastrointestinal illness, reaching the gut via the consumption of contaminated foods. When Salmonella spp. breach the intestinal epithelial layer for the first time, the adaptive immune system fronts a primary response. After clearance of the primary infection, if a Salmonella infection occurs again, the immune system can front a secondary response, which is often more effective.
Identify whether each adaptive immune cell functions in the primary or secondary immune response. Then, complete the statements about the homing locations of gastrointestinal immune cells that respond to infections such as Salmonella.
a. naive B cells
b. memory B cells
c. naive T cells
d. central memory T cells
