Altered immunity of laboratory mice in the natural environment is associated with fungal colonization
Journal
Cell Host & Microbe
Journal Volume
27
Journal Issue
5
Pages
809-822
Date Issued
2020
Author(s)
Frank Yeung
Abstract
Free-living mammals, such as humans and wild mice, display heightened immune activation compared with artificially maintained laboratory mice. These differences are partially attributed to microbial exposure as laboratory mice infected with pathogens exhibit immune profiles more closely resembling that of free-living animals. Here, we examine how colonization by microorganisms within the natural environment contributes to immune system maturation by releasing inbred laboratory mice into an outdoor enclosure. In addition to enhancing differentiation of T cell populations previously associated with pathogen exposure, outdoor release increased circulating granulocytes. However, these “rewilded” mice were not infected by pathogens previously implicated in immune activation. Rather, immune system changes were associated with altered microbiota composition with notable increases in intestinal fungi. Fungi isolated from rewilded mice were sufficient in increasing circulating granulocytes. These findings establish a model to investigate how the natural environment impacts immune development and show that sustained fungal exposure impacts granulocyte numbers. © 2020 Elsevier Inc.Laboratory mice are maintained in artificial conditions that potentially impact immunity. In this issue of Cell Host & Microbe, Yeung et al. (2020) demonstrate that mice released into a wild enclosure display increases in circulating granulocytes that are associated with an altered microbiota, notably expansion of fungi. © 2020 Elsevier Inc.
Subjects
Aspergillus; fungi; granulocytes; laboratory mice; mesocosm; microbiota; mycobiota; neutrophils; rewilding; wild mice
Other Subjects
animal cell; animal experiment; article; Aspergillus; cell population; controlled study; experimental mouse; fungal colonization; immunomodulation; male; mesocosm; microflora; microorganism; mouse; neutrophil; nonhuman; T lymphocyte; animal; C57BL mouse; CD8+ T lymphocyte; environment; feces; female; fungus; genetics; granulocyte; growth, development and aging; immune system; immunology; intestine; intestine flora; isolation and purification; knockout mouse; lymphocyte; microbiology; mycobiome; pathology; physiology; Atg16l1 protein, mouse; autophagy related protein; caspase recruitment domain protein 15; Nod2 protein, mouse; Animals; Autophagy-Related Proteins; CD8-Positive T-Lymphocytes; Environment; Feces; Female; Fungi; Gastrointestinal Microbiome; Granulocytes; Immune System; Intestines; Lymphocytes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Mycobiome; Nod2 Signaling Adaptor Protein
Publisher
Elsevier Inc.
Type
journal article