生物谷报道：过去普遍的看法，毛囊一旦受损，可能永远无法修复。 但日前，在老鼠表皮上帮助培植新毛发细胞的科学家表示，人类脱发并非是不可逆的。
美国宾夕法尼亚大学的一个研究小组在《自然》杂志上报告说，实际上可以利用一种单基因促使毛发再生。英国的一位专家表示，这项研究可能在辅助伤口愈合技术方面有着更为重要的意义。人们普遍认为，在人的一生中不会再长出新的毛囊。宾夕法尼亚州的这个研究小组发现，在伤口愈合方面起着重要作用的wnt基因好像可以促进新毛囊的生长。
研究人员表示，他们的发现不仅为秃顶的治疗打开了一扇窗户，而且对伤口愈合和再生方面的治疗也起着重要的作用。来自布拉德福大学的英国专家德斯·托宾教授说：“这篇报告提供了有力的证据，说明皮肤拥有超强的再生能力，不仅仅是先前就已经知道的修复能力。这份观察报告的隐含意义有很多，但它或许主要是为了给我们讲述成人干细胞的再生能力，以及它在再生医学和伤口愈合方面的应用。”
原始出处:
Nature 447, 316-320 (17 May 2007) | doi:10.1038/nature05766; Received 30 August 2006; Accepted 20 March 2007
Wnt-dependent de novo hair follicle regeneration in adult mouse skin after wounding
Mayumi Ito1, Zaixin Yang1, Thomas Andl1, Chunhua Cui1, Noori Kim1, Sarah E. Millar1 & George Cotsarelis1
Department of Dermatology, Kligman Laboratories, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
Correspondence to: George Cotsarelis1 Correspondence and requests for materials should be addressed to G.C. (Email: cotsarel@mail.med.upenn.edu).
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Abstract
The mammalian hair follicle is a complex 'mini-organ' thought to form only during development1; loss of an adult follicle is considered permanent. However, the possibility that hair follicles develop de novo following wounding was raised in studies on rabbits2, 3, mice4 and even humans fifty years ago5. Subsequently, these observations were generally discounted because definitive evidence for follicular neogenesis was not presented6. Here we show that, after wounding, hair follicles form de novo in genetically normal adult mice. The regenerated hair follicles establish a stem cell population, express known molecular markers of follicle differentiation, produce a hair shaft and progress through all stages of the hair follicle cycle. Lineage analysis demonstrated that the nascent follicles arise from epithelial cells outside of the hair follicle stem cell niche, suggesting that epidermal cells in the wound assume a hair follicle stem cell phenotype. Inhibition of Wnt signalling after re-epithelialization completely abrogates this wounding-induced folliculogenesis, whereas overexpression of Wnt ligand in the epidermis increases the number of regenerated hair follicles. These remarkable regenerative capabilities of the adult support the notion that wounding induces an embryonic phenotype in skin, and that this provides a window for manipulation of hair follicle neogenesis by Wnt proteins. These findings suggest treatments for wounds, hair loss and other degenerative skin disorders.
