Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany
Karin Zimmermann
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany
Lisa Katharina Wagner
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany
Dorothea Dörr
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany; Institute of Biology, Humboldt University of Berlin, Berlin, Germany
Christoph SN Klose
Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Microbiology, Infectious Diseases and Immunology, Charité Berlin, Berlin, Germany
Cornelius Fischer
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany
Institute of Dental Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
Avi-Hai Hovav
Institute of Dental Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
Werner Stenzel
Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neuropathology, Charité Berlin, Berlin, Germany
Steffen Dommerich
Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Otorhinolaryngology, Charité Berlin, Berlin, Germany
Thomas Conrad
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany
Achim Leutz
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany; Institute of Biology, Humboldt University of Berlin, Berlin, Germany
Max-Delbrück-Center for Molecular Medicine Berlin, Berlin, Germany; InFLAMES Research Flagship Center, University of Turku, Turku, Finland; Institute of Biomedicine, Medicity, University of Turku, Turku, Finland
The tongue is a unique muscular organ situated in the oral cavity where it is involved in taste sensation, mastication, and articulation. As a barrier organ, which is constantly exposed to environmental pathogens, the tongue is expected to host an immune cell network ensuring local immune defence. However, the composition and the transcriptional landscape of the tongue immune system are currently not completely defined. Here, we characterised the tissue-resident immune compartment of the murine tongue during development, health and disease, combining single-cell RNA-sequencing with in situ immunophenotyping. We identified distinct local immune cell populations and described two specific subsets of tongue-resident macrophages occupying discrete anatomical niches. Cx3cr1+ macrophages were located specifically in the highly innervated lamina propria beneath the tongue epidermis and at times in close proximity to fungiform papillae. Folr2+ macrophages were detected in deeper muscular tissue. In silico analysis indicated that the two macrophage subsets originate from a common proliferative precursor during early postnatal development and responded differently to systemic LPS in vivo. Our description of the under-investigated tongue immune system sets a starting point to facilitate research on tongue immune-physiology and pathology including cancer and taste disorders.
