Scleraxis-lineage cell depletion improves tendon healing and disrupts adult tendon homeostasis
- University of Rochester Medical Center, United States
Abstract
Despite the requirement for Scleraxis-lineage (ScxLin) cells during tendon development, the function of ScxLin cells during adult tendon repair, post-natal growth, and adult homeostasis have not been defined. Therefore, we inducibly depleted ScxLin cells (ScxLinDTR) prior to tendon injury and repair surgery and hypothesized that ScxLinDTR mice would exhibit functionally deficient healing compared to wildtype littermates. Surprisingly, depletion of ScxLin cells resulted in increased biomechanical properties without impairments in gliding function at 28 days post-repair, indicative of regeneration. RNA sequencing of day 28 post-repair tendons highlighted differences in matrix-related genes, cell motility, cytoskeletal organization, and metabolism. We also utilized ScxLinDTR mice to define the effects on post-natal tendon growth and adult tendon homeostasis and discovered that adult ScxLin cell depletion resulted in altered tendon collagen fibril diameter, density, and dispersion. Collectively, these findings enhance our fundamental understanding of tendon cell localization, function, and fate during healing, growth, and homeostasis.
Data availability
Sequencing data have been deposited in GEO under accession code GSE156157. All other data generated during this study are included in the manuscript and supporting files.
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Single cell transcriptional atlas of mouse Achilles tendonsNCBI Gene Expression Omnibus, GSE138515.
Article and author information
Author details
Funding
National Institute of Arthritis and Musculoskeletal and Skin Diseases (F31 AR074815)
- Katherine T Best
National Institute of Arthritis and Musculoskeletal and Skin Diseases (K01AR068386)
- Alayna E Loiselle
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR073169)
- Alayna E Loiselle
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR070765)
- Mark R Buckley
National Institute of Arthritis and Musculoskeletal and Skin Diseases (T32 AR076950)
- Anne EC Nichols
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approval by the University Committee on Animal Resources (UCAR) for protocols #2014-004E and 2017-030 at the University of Rochester. All surgery was performed under ketamine anesthesia, and every effort was made to minimize suffering.
Copyright
© 2021, Best 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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Scleraxis-lineage cell depletion improves tendon healing and disrupts adult tendon homeostasis
eLife 10:e62203.
https://doi.org/10.7554/eLife.62203
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