Salmonella Typhimurium Is a Gram-Negative Bacterial Pathogen That Infects Its $\gamma$

Multiple Choice

Salmonella typhimurium is a Gram-negative bacterial pathogen that infects its host via the gastrointestinal (GI) tract. Early in infection, the bacteria enter and replicate in gut epithelial cells, where the infection provokes a type 3 response, including the development of T_H17 cells, in the GI tract. However, this type 3 response in the GI tract does not eradicate the pathogen, as S. typhimurium has evolved strategies to evade the T_H17 response and to spread systemically by infecting and replicating in macrophages. Therefore, a second phase of the immune response is required to completely eliminate the pathogen from the body, as has been demonstrated in mouse models of S. typhimurium infection. These experiments in mouse models likely showed that:

A) IFN- $\gamma$ is required to clear S. typhimurium from the body.
B) IL-17 is required to clear S. typhimurium from the body.
C) IL-22 is required to clear S. typhimurium from the body.
D) IL-13 is required to clear S. typhimurium from the body.
E) IL-4 is required to clear S. typhimurium from the body.