IADR Abstract Archives

Title: Using the Mouse Incisor to Understand Stem Cell-Based Tooth Regeneration

Objectives: The mouse incisor is an excellent model system for exploring the involvement of stem cells in renewal of dental tissues because it grows continuously throughout life. This growth is supported by epithelial and mesenchymal stem cells residing at the incisor’s proximal end. These stem cells can self-renew and differentiate into all cell types of the adult tooth, including ameloblasts and odontoblasts, which secrete enamel and dentin, respectively. This study aimed to classify systematically the cells that compose the mouse incisor epithelium, and determine how these cells react to damage.
Methods: We performed a single-cell RNA-seq analysis of the mouse incisor epithelium, which enables transcriptional profiling of thousands of individual cells. We then used single-molecule in situ hybridization to map these cell types back to their location within the tissue, integrating these data with quantitative proliferation kinetics and genetic lineage tracing. Finally, we examined how these cell types change their compositions and function during a repair process.
Results: We uncovered cell behaviors that challenge the current dogma about the identity, location and function of progenitor cells in this tissue. We demonstrate that self-renewing cells are abundant (not rare), they cycle frequently (not slowly), and they can move in multiple directions (not unidirectionally). Comparison of homeostatic and post-damage recovery states uncovered the mechanisms whereby stem cells respond to stress, including recruitment of reserve cells, changes in cell cycle, and delayed differentiation.
Conclusions: This study advances our understanding on how the mouse incisor epithelial cells cooperate and interact as a functional unit to continuously generate ameloblasts in steady state and during repair.

2021 Israeli Division Meeting (Jerusalem, Israel)

2021

  • Sharir, Amnon  ( Hebrew University of Jerusalem Faculty of Science , Jerusalem , Israel )
  • Klein, Ophir  ( University of California San Francisco , San Francisco , California , United States )
  • Marangoni, Pauline  ( University of California San Francisco , San Francisco , California , United States )
  • None
    NIH K08-DE026219
    Oral Session
    Oral Session 1