Characterization of the Skin Immune System in Dirty Mice in Homeostasis and Disease

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Presentation Time: 03:15 PM - 04:30 PM
Poster Board Number: B212
Abstract ID: 7976

Presenting Author:
Xiaopeng Fu , postdoc at Brigham and Women’s Hosp, Harvard Med. Sch.

Abstract:

Mouse modeling is critical to understanding skin immunity and disease, but there are often limitations translating findings from traditional mouse models to humans. Recent data suggest that mice co-housed with petshop mice, i.e. “dirty mice” acquire a diverse microbiome and subsequent immune system that better recapitulates that of humans. ‘Dirty mice’ may therefore yield more translatable data. We aimed to characterize the skin immune system in dirty mice. Dirty mice consistently developed a robust T cell effector response resulting in generation of memory T cells in secondary lymphoid organs, blood, and skin. Skin T cells after resolution of inflammation expressed a phenotype consistent with resident memory T cells (TRM) (CD62Llow CD44high CD69+, with the majority expressing CD103+). Skin TRM included CD4+, CD8+ and γδ (epidermal and dermal type) T cell subsets and appeared to be Th17 skewed. Monocytes and granulocytes were also increased in post-resolution skin. Generation of persisting regulatory T cells, macrophages, and dendritic cells in skin varied across batches of co-housed mice. A subset of dirty, but not petshop mice spontaneously developed atopic-like dermatitis, suggesting potential propensity for autoimmunity in mice exposed to new microbiota later in life. Further work is necessary to identify the mechanistic underpinnings of this observation.