TLDR Basal layer skin cells help form the epidermis and hair follicles.
The study investigated the distribution and characteristics of cutaneous stem cells in human fetal skin during embryogenesis, using immunohistochemical methods to analyze their differentiation into epidermis and hair follicles. It found that integrins β1 and K19 were coexpressed in the undifferentiated epidermis, with β1 expression downregulated during follicular keratinization. K14 was differentially expressed in the basal and spinous layers, while K10 was in the differentiated spinous and granular layers. Epidermal progenitor cells were mainly located in the basal layer and hair follicle structures, expressing integrins β1, K19, K14, and PCNA. The study concluded that basal layer cutaneous cells contribute to epidermis and hair follicle development, with mesenchymal cues also playing a role in hair follicle formation and cycling.
16 citations
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July 2019 in “Biochemical and Biophysical Research Communications” CD36-expressing dermal sheath cells help form blood vessels in hair follicles, aiding hair growth.
96 citations
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July 2014 in “Cold Spring Harbor Perspectives in Medicine” The document concludes that adult mammalian skin contains multiple stem cell populations with specific markers, important for understanding skin regeneration and related conditions.
24 citations
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April 2012 in “Developmental Biology” Dermal papillae cells, important for hair growth, come from multiple cell lines and can be formed by skin cells, regardless of their origin or hair cycle phase. These cells rarely divide, but their ability to shape tissue may contribute to their efficiency in inducing hair growth.
15 citations
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September 2009 in “European Journal of Histochemistry” 
7 citations
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March 2005 in “Journal of dermatological science” Apoptosis helps shape hair growth and prepares the skin for hair to emerge.
55 citations
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January 2004 in “The International Journal of Developmental Biology” Corneal cells can transform into hair-producing skin cells when exposed to certain signals.
41 citations
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September 2003 in “Journal of Investigative Dermatology” Overexpression of COX-2 causes early hair loss in mice, but can be prevented with a COX-2 inhibitor.
1010 citations
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August 2000 in “Cell” Hair follicle stem cells can form both hair follicles and skin.
87 citations
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February 2000 in “Journal of Investigative Dermatology”