Article

Langton AK, Herrick SE, Headon DJAn extended epidermal response heals cutaneous wounds in the absence of a hair follicle stem cell contribution. J Invest Dermatol 128:1311-1318

Faculty of Life Sciences, University of Manchester, Manchester, UK.
Journal of Investigative Dermatology (Impact Factor: 6.37). 06/2008; 128(5):1311-8. DOI: 10.1038/sj.jid.5701178
Source: PubMed

ABSTRACT Hair follicles have been observed to provide a major cellular contribution to epidermal healing, with emigration of stem-derived cells from the follicles aiding in wound reepithelialization. However, the functional requirements for this hair follicle input are unknown. Here we have characterized the keratinocyte stem cell status of mutant mice that lack all hair follicle development on their tail, and analyzed the consequent alterations in epidermal wound healing rate and mechanisms. In analyzing stem cell behavior in embryonic skin we found that clonogenic keratinocytes are relatively frequent in the ectoderm prior to hair follicle formation. However, their frequency in the interfollicular epidermis drops sharply by birth, at which time the majority of stem cells are present within the hair follicles. We find that in the absence of hair follicles cutaneous wounds heal with an acute delay in reepithelialization. This delay is followed by expansion of the region of activated epidermis, beyond that seen in normal haired skin, followed by appropriate wound closure. JID Journal Club article: for questions, answers, and open discussion about this article please go to http://network.nature.com/group/jidclub.

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    • "Compartmentalization IFE SCs have been shown to be the major contributor to tissue regeneration following injury (Mascré et al., 2012); however, evidence from hairless mice and lineage tracing from pilosebaceous SCs supports a role for these cells in the regenerative response (Brownell et al., 2011; Ito et al., 2005; Langton et al., 2008; Snippert et al., 2010). It has also not been clear to what extent cells were specifically retained in the IFE following tissue repair based on their ancestry (Plikus et al., 2012). "
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