Identification of a nerve-associated, lung-resident interstitial macrophage subset with distinct localization and immunoregulatory properties [scRNA-seq]

ABSTRACT: Tissue-resident macrophages are a diverse population of cells that perform specialized functions including sustaining tissue homeostasis and tissue surveillance. Here we report an interstitial subset of CD169+ lung-resident macrophages that are transcriptionally and developmentally distinct from alveolar macrophages (AMs). They are primarily localized around the airways and are found in close proximity to the sympathetic nerves located in the bronchovascular bundle. These nerve- and airway-associated macrophages (NAMs) are tissue-resident, yolk sac-derived, self-renewing, and do not require CCR2+ monocytes for development or maintenance. Unlike AMs, the development of NAMs requires CSF1, but not GM-CSF. Bulk population and single cell transcriptome analysis indicated that NAMs are distinct from other lung resident macrophage subsets and highly express immunoregulatory genes under steady state and inflammatory conditions. NAMs proliferated robustly following influenza infection and activation with the TLR ligand poly I:C, and in their absence, the inflammatory response was augmented resulting in excessive production of inflammatory cytokines and innate immune cell infiltration. Overall, our study provides insights into a distinct subset of airway-associated pulmonary macrophages that function to maintain immune and tissue homeostasis.

ORGANISM(S): Mus musculus

PROVIDER: GSE146682 | GEO | 2020/03/10

REPOSITORIES: GEO