BACKGROUND The dermal papilla (DP) interacts with epithelial cells for folliculogenesis. For translational research on cell therapies for hair regrowth with cultured human DP cells (hDPCs), a model to evaluate the capacity of hDPCs to induce hair formation is inevitable. METHODS Chamber models were constructed by transplanting 4 different combinations of mouse or human epithelial and mesenchy...

We have developed a method where, after glutaraldehyde fixation, human hair shafts and insect cuticles are treated with ammonium thioglycolate (ATG) to improve ultrastructural staining. Conventional transmission electron microscopic (TEM) preparations do not distinguish the A-layer and the exocuticles of hair shafts. However, after ATG treatment, the A-layer appears in higher contrast. ATG trea...

Hair is maintained through a cyclic process that includes periodic regeneration of hair follicles in a stem cell-dependent manner. Little is known, however, about the cellular and molecular mechanisms that regulate the layered differentiation of the hair follicle. We have established a mutant mouse with a cyclic alopecia phenotype resulting from the targeted disruption of Sox21, a gene that enc...

EJD n° 4, vol. 11, July-August 2001 Hair loss or hair thinning is a common complaint in clinical dermatology and patients seeking advice for hair loss are not necessarily bald. In established cases of androgenetic alopecia (AGA) characteristic patterns are easily discernible. However, especially in females the clinician is often challenged by patients with initial stages of AGA where hair loss ...

Hair follicles are complex skin appendages, the perturbations of which have an impact on human health and emotional welfare disproportionate to their small dimensions. Changes to the parameters of hair follicle size, numbers per unit area of skin, and growth cycle time duration determine hair coverage and fundamentally underlie the diagnosis of an individual with alopecia or hypertrichosis. Her...

In this short review, I introduce an integrated vision of human hair follicle behavior and describe opposing influences that control hair follicle homeostasis, from morphogenesis to hair cycling. The interdependence and complementary roles of these influences allow us to propose that the hair follicle is a true paradigm of a "Yin Yang" type, that is a cold/slow-hot/fast duality. Moreover, a new...

BACKGROUND There is evidence that glycosaminoglycans (GAGs) are present in the hair shaft within the follicle but there are no studies regarding GAGs isolation and measurement in the human hair shaft over the scalp surface, it means, in the free hair shaft. OBJECTIVE The purpose of our research was to isolate and measure the total GAGs from human free hair shaft. METHODS Seventy-five health...

Hair morphology differs dramatically between human populations: people of East Asian ancestry typically have a coarse hair texture, with individual fibers being straight, of large diameter, and cylindrical when compared to hair of European or African origin. Ectodysplasin-A receptor (EDAR) is a cell surface receptor of the tumor necrosis factor receptor (TNFR) family involved in the development...

BACKGROUND Androgenetic alopecia (AGA) is a common problem in men of all ages, affecting approximately 50% at 50 years of age. The underlying cause is an androgen-dependent miniaturization of genetically predetermined hair follicles. Here, the hair organ culture model was used to investigate the effects of testosterone and caffeine; the latter being a promising candidate for hair growth stimula...