Vibrissa hair bulge houses two populations of skin epithelial stem cells distinct by their keratin profile

Danielle Larouche, Xuemei Tong, Julie Fradette, Pierre A. Coulombe, Lucie Germain

Research output: Contribution to journalArticle

Abstract

Defining the properties of postnatal stem cells is of interest given their relevance for tissue homeostasis and therapeutic applications, such as skin tissue engineering for burn patients. In hair follicles, the bulge region of the outer root sheath houses stem cells. We show that explants from the prominent bulge area, but not the bulb, in rodent vibrissa follicles can produce epidermis in a skin model of tissue engineering. Using morphological criteria and keratin expression, we typified epithelial stem cells of vibrissa bulge. Two types of slow-cycling cells (Bb, Bs1) featuring a high colony-forming capacity occur in the bulge. Bb cells are located in the outermost basal layer, express K5, K15, K17, and K19, and feature a loosely organized keratin network. Bs1 cells localize to the suprabasal layers proximal to Bb cells and express K5/K17, correlating with a network of densely bundled filaments. These prominent bundles are missing in K17-null mice, which lack vibrissa. Atypically, both the Bb and Bs1 keratinocytes lack K14 expression. These findings show heterogeneity within the hair follicle stem cell repository, establish that a subset of slow-cycling cells are suprabasal in location, and point to a special role for K5/K17 filaments in a newly defined subset of stem cells. Our results are discussed in the context of long-term survival of engineered tissues after grafting that requires the presence of stem cells.

Original languageEnglish (US)
Pages (from-to)1404-1415
Number of pages12
JournalFASEB Journal
Volume22
Issue number5
DOIs
StatePublished - May 1 2008

Keywords

  • Intermediate filaments
  • Rodent
  • Tissue engineering
  • Transmission electron microscopy

ASJC Scopus subject areas

  • Biotechnology
  • Biochemistry
  • Molecular Biology
  • Genetics

Fingerprint Dive into the research topics of 'Vibrissa hair bulge houses two populations of skin epithelial stem cells distinct by their keratin profile'. Together they form a unique fingerprint.

  • Cite this