The FMTs from patients with IBD also increased NF-κB+/Iba1+, and LPS+/Iba1+, and IL-1R+ cell populations, as well as IL-1β expression in the hippocampus, while the BDNF+/NeuN+ cell population reduced (Fig. 2f,g). Here, NFKB1 is linked to inflammatory bowel disease.