The intermediate filament protein, nestin, marks progenitor cells of the CNS. Such CNS stem cells are selectively labeled by placing GFP under the control of the nestin regulatory sequences. During early anagen or growth phase of the hair follicle, nestin-expressing cells, marked by GFP fluorescence in nestin-GFP transgenic mice, appear in the permanent upper hair follicle immediately below the...

Integrin-linked kinase (ILK) is key for normal epidermal morphogenesis, but little is known about its role in hair follicle stem cells and epidermal regeneration. Hair follicle stem cells are important contributors to newly formed epidermis following injury. We inactivated the Ilk gene in the keratin 15--expressing stem cell population of the mouse hair follicle bulge. Loss of ILK expression in...

Skin and hair follicle stem cell biology is the focus of increasing interest, not least because the adult hair follicle has well defined dermal and epithelial populations that display distinct developmental properties. Recent evidence suggests that a number of adult cell populations have much broader stem cell capabilities than previously thought. To examine whether this applied to the hair fol...

One challenge faced by stem cell biologists is the bioengineering of an organ. Ehama et al. (2007, this issue) used cells derived from human and rodent epidermis and dermal papilla to reconstitute hair-follicle mini-organs. Some result in hair follicles; others are hair follicle-like. The challenge calls for the development of a set of criteria to define a hair follicle so that bioengineered pr...

Panfolliculoma is a distinctive and unusual benign follicular neoplasm. It shows differentiation towards all components of the hair follicle, including the upper and the lower segments. We report two cases of this rare disease. The first patient presented with a painful nodule on the scalp and the second patient had an asymptomatic skin-colored nodule on his left eyebrow. Histopathologic examin...

Ten years ago, Hardy (1992) wrote a timely review on the major features of hair follicle development and hair growth which she referred to as a secret life. Many of these secrets are now being revealed. The information discussed in this brief review comprises the structure of the hair and hair follicle, the continuing characterisation of the genes for keratin and keratin associated proteins, th...

The Wnt and Notch signalling pathways regulate hair follicle maintenance, but how they intersect is unknown. We show that Notch signalling is active in the hair follicle pre-cortex, a region of high Wnt activity, where commitment to hair lineages occurs. Deletion of jagged 1 (Jag1) results in inhibition of the hair growth cycle and conversion of hair follicles into cysts of cells undergoing int...

Surface appendages such as bristles, feathers and hairs exhibit both long- and short-range order. In the frizzled 6 null (Fz6(-/-)) mouse the orientations of the earliest born hair follicles are uncorrelated, but over time the follicles reorient to create patterns that are characterized by a high degree of local order. By quantifying follicle orientations over time, in both living and fixed tis...

Hair can be strategically divided into two distinct parts: the hair follicle, deeply buried in the skin, and the visible hair fiber. The study of the hair follicle is mainly addressed by biological sciences while the hair fiber is mainly studied from a physicochemical perspective by cosmetic sciences. This paper reviews the key topics in hair follicle biology and hair fiber biochemistry, in par...

INTRODUCTION Stem cells from hair follicle have great therapeutic applications in regenerative medicine as sources of cells for transplantation. The differentiation pathway selected by hair follicle stem cells (HFSC) is largely determined by local microenvironmental signals. In this study, human hair follicle stem cells were treated with Notch signaling blocker to explore a new approach to modu...