Tendon injuries are common problems for active individuals and aging adults. Although surgical intervention can restore strength and mobility, frequent complications, such as a high failure rate and pain associated with movement, often occur. An improved understanding of the molecular and cellular mechanisms regulating tendon tissue maintenance, cell renewal, and injury response would have significant therapeutic implications. Studies have shown that cells from tendon tissues have stem/progenitor cell characteristics, and they are thought to contribute to tendon tissue homeostasis and repair. However, these studies were performed after extraction and expansion in culture, and our current knowledge as to the in vivo behaviors of these cells during maintenance and injury response is very limited. In addition, we have no means to prospectively identify, genetically target, and study unique tendon cell populations in their native environment. We propose to employ lineage tracing strategies to study cell turnover rates, gene expression, and functional properties of a uniquely genetically labeled tendon cell subset in vivo. Using these approaches, we will test the hypothesis that this specifically labeled subset of tendon cells are resident tendon progenitors and that a specific pathway is required for proper tendon healing responses. Knowledge of this distinct cell population will impact our fundamental understanding of the diversity of cell types within the tendon and would significantly advance our ability to directly isolate and genetically manipulate these cells. This work is a crucial step towards studying unique tendon progenitor cell populations in their native environment and will provide the foundation for future studies aimed at elucidating mechanisms regulating their activities.

Public Health Relevance

Tendon injuries are widespread and often result in pain and limited mobility, and yet we have little knowledge of the molecular mechanisms regulating adult tendon cells. This proposal aims to advance our understanding of a unique tendon cell population and pathway during homeostasis and repair. Discoveries from this research would impact the development of treatments for tendon injuries in humans.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AR072294-01
Application #
9375253
Study Section
Skeletal Biology Structure and Regeneration Study Section (SBSR)
Program Officer
Washabaugh, Charles H
Project Start
2017-09-01
Project End
2019-08-31
Budget Start
2017-09-01
Budget End
2018-08-31
Support Year
1
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Massachusetts General Hospital
Department
Type
DUNS #
073130411
City
Boston
State
MA
Country
United States
Zip Code
02114
Grinstein, Mor; Dingwall, Heather L; Shah, Rishita R et al. (2018) A robust method for RNA extraction and purification from a single adult mouse tendon. PeerJ 6:e4664