PT - JOURNAL ARTICLE AU - Daniel Schulz AU - Dorothee Grumann AU - Patricia Trübe AU - Kathleen Pritchett-Corning AU - Sarah Johnson AU - Kevin Reppschläger AU - Janine Gumz AU - Nandakumar Sundaramoorthy AU - Stephan Michalik AU - Sabine Berg AU - Jens van den Brandt AU - Richard Fister AU - Stefan Monecke AU - Benedict Uy AU - Frank Schmidt AU - Barbara M. Bröker AU - Siouxsie Wiles AU - Silva Holtfreter TI - Natural Colonization of Laboratory Mice with <em>Staphylococcus aureus</em> Primes a Systemic Immune Response AID - 10.1101/114314 DP - 2017 Jan 01 TA - bioRxiv PG - 114314 4099 - http://biorxiv.org/content/early/2017/03/06/114314.short 4100 - http://biorxiv.org/content/early/2017/03/06/114314.full AB - Background Whether mice are an appropriate model for S. aureus infection and vaccination studies is a matter of debate, because they are not considered as natural hosts of S. aureus. Sparked by an outbreak of S. aureus infections in laboratory mice, we investigated whether laboratory mice are commonly colonized with S. aureus and whether this might impact on infection experiments.Methods We characterized 99 S. aureus isolates from laboratory mice (spa typing, virulence gene PCR), and quantified murine antibodies using FlexMap technology.Results Specific-pathogen-free mice from various vendors were frequently colonized with S. aureus (0-21%). S. aureus was readily transmitted from murine parents to offspring, which became persistently colonized. Most murine isolates belonged to the lineage CC88 (54%). Murine strains showed features of host adaptation, such as absence of hlb-converting phages and superantigen genes, as well as enhanced coagulation of murine plasma. Importantly, S. aureus colonization induced a systemic IgG response specific for numerous S. aureus proteins, including several vaccine candidates.Conclusion Laboratory mice are natural hosts of S. aureus and, therefore, provide better infection models than previously assumed. Pre-exposure to S. aureus is a possible confounder in S. aureus infection and vaccination studies.