Functionally heterogeneous human satellite cells identified by single cell RNA sequencing
Abstract
Although heterogeneity is recognized within the murine satellite cell pool, a comprehensive understanding of distinct subpopulations and their functional relevance in human satellite cells is lacking. We used a combination of single cell RNA sequencing and flow cytometry to identify, distinguish, and physically separate novel subpopulations of human PAX7+ satellite cells (Hu-MuSCs) from normal muscles. We found that, although relatively homogeneous compared to activated satellite cells and committed progenitors, the Hu-MuSC pool contains clusters of transcriptionally distinct cells with consistency across human individuals. New surface marker combinations were enriched in transcriptional subclusters, including a subpopulation of Hu-MuSCs marked by CXCR4/CD29/CD56/CAV1 (CAV1+). In vitro, CAV1+ Hu-MuSCs are morphologically distinct, and characterized by resistance to activation compared to CAV1- Hu-MuSCs. In vivo, CAV1+ Hu-MuSCs demonstrated increased engraftment after transplantation. Our findings provide a comprehensive transcriptional view of normal Hu-MuSCs and describe new heterogeneity, enabling separation of functionally distinct human satellite cell subpopulations.
Data availability
Single cell rna sequencing data were uploaded to Dryad and can be accessed under the doi: 10.7272/Q65X273X
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Functionally heterogeneous human satellite cells identified by single cell RNA sequencingDryad Digital Repository, 10.7272/Q65X273X.
Article and author information
Author details
Funding
California Institute for Regenerative Medicine (New Faculty Physician Scientist Award RN3-06504)
- Jason H Pomerantz
National Institutes of Health (R01AR072638-03)
- Jason H Pomerantz
University of California, San Francisco (UCSF PROF-PATH program via NIH R25MD006832)
- Steven M Garcia
University of California, San Francisco (Research Allocation Program for trainees)
- Solomon Lee
Eli and Edythe Broad Foundation (Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research Fellowship)
- Alvin Wong
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 procedures were approved and performed in accordance with the UCSF Institutional Animal Care and Use Committee (Protocols #181101).
Human subjects: This study was conducted under the approval of the Institutional Review Board at The University of California San Francisco (UCSF). Written informed consent was obtained from all subjects.
Copyright
© 2020, Barruet 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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