Bulge Region as a Putative Hair Follicle Stem Cells Niche: A Brief Review

  • Sanaz JOULAI VEIJOUYE Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran
  • Abazar YARI Dept. of Anatomy, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
  • Fatemeh HEIDARI Dept. of Anatomy, School of Medicine, Qom University of Medical Sciences, Qom, Iran
  • Nayereh SAJEDI Dept. of Anatomy, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
  • Fatemeh GHOROGHI MOGHANI Dept. of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  • Maliheh NOBAKHT Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran Dept. of Anatomy, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran Anti-Microbial Resistance Research Center, Iran University of Medical Sciences, Tehran, Iran
Keywords: Bulge, Hair follicle, Stem cell, Regeneration, Pluripotent, Self-renewal


 Background: Hair follicle stem cells exist in different sites. Most of the hair follicle stem cells are reside in niche called bulge. Bulge region is located between the opening of sebaceous gland and the attachment site of the arrector pili muscle.Methods: Data were collected using databases and resources of PubMed, Web of Science, Science Direct, Scopus, MEDLINE and their references from the earliest available published to identify English observational studies on hair follicle bulge region.Results: Bulge stem cells are pluripotent with high proliferative capacity. Specific markers allow the bulge cells to be isolated from mouse or human hair follicle. Stem cells isolated from bulge region are label retaining and slow cycling hence these cells are defined as label-retaining cells. Bulge cell populations, due to their plasticity nature are able to differentiate into distinct linage and could contribute in tissue regeneration.Conclusion: The current review discuss about bulge stem cells characteristics and biology including their cycle, location, plasticity, specific markers and regenerative nature. Also the differences between mouse and human hair follicles are investigated.  


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How to Cite
JOULAI VEIJOUYE S, YARI A, HEIDARI F, SAJEDI N, GHOROGHI MOGHANI F, NOBAKHT M. Bulge Region as a Putative Hair Follicle Stem Cells Niche: A Brief Review. Iran J Public Health. 46(9):1167-1175.
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