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Updated: Jul 12, 2025

Rapid Genetic Analysis of Epithelial-Mesenchymal Signaling During Hair Regeneration
10:09

Rapid Genetic Analysis of Epithelial-Mesenchymal Signaling During Hair Regeneration

Published on: February 28, 2013

13.8K

Apoptotic cells may drive cell death in hair follicles during their regression cycle

Bradley D Keister1, Kailin R Mesa2,3, Krastan B Blagoev1,4,5,6

  • 1National Science Foundation, Physics Division, Alexandria, VA 22230, USA.

Oncotarget
|October 20, 2023
PubMed

Insights

During hair follicle regression, dying cells trigger apoptosis in neighboring cells. This wave slows near stem cells, suggesting a pro-survival signal protects them.

Area of Science:

  • Cell biology
  • Dermatology
  • Developmental biology

Background:

  • Hair follicle regression involves epithelial cell elimination via apoptosis.
  • Mesenchymal-epithelial interactions, particularly transforming growth factor-beta (TGF-β), are crucial for initiating apoptosis.
  • The dermal papilla (DP) induces apoptosis, but its role in propagating cell death towards stem cells remains unclear.

Purpose of the Study:

  • To investigate the mechanism of apoptosis propagation during hair follicle regression.
  • To determine how the regenerative stem cell population is spared from apoptosis.

Main Methods:

  • Quantitative analysis of hair follicle length during regression in live mice.
  • Intravital microscopy to observe cellular dynamics.

Main Results:

  • Apoptosis propagates through neighboring cells, akin to a wave.
  • The rate of apoptosis slows as it nears the stem cell population.
  • This deceleration suggests a pro-survival signal gradient emanating from stem cells.

Conclusions:

  • Apoptosis propagation during hair follicle regression is likely driven by a cell-to-cell induction mechanism.
  • Hair follicle stem cells are protected by a pro-survival signal gradient.
  • A falsifiable experiment is proposed to test this mechanism.
Keywords:
analysishair folliclemathematical modelregression cyclestem cells

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