Combined transient ablation and single cell RNA sequencing reveals the development of medullary thymic epithelial cells
- Stanford University, United States
- University of California, San Francisco, United States
- European Molecular Biology Laboratory, Germany
Abstract
Medullary thymic epithelial cells (mTECs) play a critical role in central immune tolerance by mediating negative selection of autoreactive T cells through the collective expression of the peripheral self-antigen compartment, including tissue-specific antigens (TSAs). Recent work has shown that gene expression patterns within the mTEC compartment are remarkably heterogenous and include multiple differentiated cell states. To further define mTEC development and medullary epithelial lineage relationships, we combined lineage tracing and recovery from transient in vivo mTEC ablation with single cell RNA-sequencing in Mus musculus. The combination of bioinformatic and experimental approaches revealed a non-stem transit-amplifying population of cycling mTECs that preceded Aire expression. Based on our findings, we propose a branching model of mTEC development wherein a heterogeneous pool of transit-amplifying cells gives rise to Aire- and Ccl21a-expressing mTEC subsets. We further use experimental techniques to show that within the Aire-expressing developmental branch, TSA expression peaked as Aire expression decreased, implying Aire expression must be established before TSA expression can occur. Collectively, these data provide a higher order roadmap of mTEC development and demonstrate the power of combinatorial approaches leveraging both in vivo models and high-dimensional datasets.
Data availability
RNA-seq data that support the findings of this study have been deposited in the GEO database under accession numbers GSE137699
Article and author information
Author details
Andreas R Gschwind
Funding
National Science Foundation (DGE- 1656518)
- Kristen L Wells
National Institutes of Health (P01 HG000205)
- Lars M Steinmetz
National Institutes of Health (R01 AI097457)
- Mark S Anderson
National Institutes of Health (R01 AI097457)
- Mark S Anderson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Mice were maintained in the University of California San Francisco (UCSF) specific pathogen- free animal facility in accordance with the guidelines established by the Institutional Animal Care and Use Committee (IACUC) and Laboratory Animal Resource Center and all experimental procedures were approved by the Laboratory Animal Resource Center at UCSF. The animal protocol number associated with the study is AN180637-02B.
Copyright
© 2020, Wells 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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