Mice with Natural Gastrointestinal Microbiota

Among 21 distinct mouse populations worldwide, we identified a closely related wild relative to standard laboratory mouse strains. Its bacterial gut microbiome differed significantly from its laboratory mouse counterpart and was transferred to and maintained in laboratory mice over several generations. Laboratory mice reconstituted with natural microbiota exhibited reduced inflammation and increased survival following influenza virus infection and improved resistance against mutagen/inflammation-induced colorectal tumorigenesis. This model should enable the discovery of mechanisms that are relevant for host fitness and protection against diseases in the natural world and improve the modeling of complex diseases of free-living mammals.