TNF and clostridium difficile infection: In accordance with this, the levels of pro-inflammatory factors, such as CXCL1, IL-36 G (IL-36γ, TNF-α, IL-6, and IL-1β, were significantly increased in the CDI group and decreased in the CDI +Iron diet group (Figure 2d–h), suggesting that high iron effectively prevented the recruitment of neutrophils to the infection site, thus reducing the inflammatory response.