Telocytes regulate macrophages in periodontal disease
Abstract
Telocytes (TCs) or interstitial cells are characterised in vivo by their long projections that contact other cell types. Although telocytes can be found in many different tissues including the heart1, lung2 and intestine3, their tissue-specific roles are poorly understood. Here we identify a specific cell signalling role for telocytes in the periodontium whereby telocytes regulate macrophage activity. We performed scRNA-seq and lineage tracing to identify telocytes and macrophages in mouse periodontium in homeostasis and periodontitis and carried out HGF signalling inhibition experiments using Tivantinib. We show that telocytes are quiescent in homeostasis, however, they proliferate and serve as a major source of HGF in periodontitis. Macrophages receive telocyte-derived HGF signals and shift from an M1 to a M1/M2 state. Our results reveal the source of HGF signals in periodontal tissue and provide new insights into the function of telocytes in regulating macrophage behaviour in periodontitis through HGF/Met cell signalling, that may provide a novel approach in periodontitis treatment.
Data availability
Sequencing data have been deposited in GEO under accession codes GSE167917 and GSE160358.
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Telocytes regulate tissue resident macrophages in periodontal diseaseNCBI Gene Expression Omnibus, GSE167917.
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Periodontal ligament tissue periodontitisNCBI Gene Expression Omnibus, GSM5115470.
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Cells in healthy periodontal ligamentNCBI Gene Expression Omnibus, GSE160358.
Article and author information
Author details
Funding
Chinese Academy of Agricultural Sciences (N/A)
- Paul T Sharpe
NIHR BioResource (N/A)
- Paul T Sharpe
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mouse work was approved by UK Home Office under the project license 70/7866 and P5F0A1579, approved by the KCL animal ethics committee.
Copyright
© 2022, Zhao et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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