NFKB1 and infection: Taken together, these observations suggest that a HF diet induces a low-grade NF-κB driven inflammatory response in the upper small intestine, which is exacerbated upon infection by Giardia. Additionally, elevated Cxcr2 gene expression, a key regulator of neutrophil recruitment, was observed in HF + G mice but not in the other groups (5.2-fold; p < 0.05) (Fig. 3b).