Recent findings suggest that two out of the four recognized families of PRRs, NLRs and TLRs, contributing to the pathogenesis of neurodevelopmental and neurodegenerative disorders through the gut-brain axis.441 Take the enteric mouse pathogen Citrobacter rodentium as an example; it induces an IL-17 reaction via mechanisms that rely on NOD1 and NOD2. 442 Mice lacking NOD1 and NOD2 exhibit heightened susceptibility to Listeria infection upon initial exposure to LPS or E. coli. The gene discussed is NOD1; the disease is listeriosis.