The results of the KEGG signaling pathway analysis demonstrated that the signature genes were most enriched in inflammatory pathways (e.g., NF-κB, TNF, Toll−like receptor, cytokine receptors, etc.); immune-related pathways (Toll−like receptor, cytokine receptors, HIF-1, NF-κB, PI3K−Akt, Ras, MAPK); microbial infection and intestinal homeostasis (HIF-1, Helicobacter pylori infection, Legionellosis, Malaria, Amoebiasis); poor blood circulation (Fluid shear stress, atherosclerosis, Lipid, Calcium) (Figure 3C). The gene discussed is TNF; the disease is legionellosis.