Additionally, FMT restores immune homeostasis via providing specific colonies of bacteria which produce SCFAs (e.g., butyrate, etc.)with histone deacetylases inhibitory (HDACi) activity that can be amplified in inflammation and infection-induced systemic immune response, thereby restoring the interferon regulatory factor 3 (IRF3) signaling pathway [50]. The gene discussed is IRF3; the disease is infection.