BACKGROUND The degree of androgenetic alopecia is generally evaluated either by global clinical scales or time-consuming methods like phototrichogram or histological studies. We describe a new clinical and reliable scoring method based on hair diameter diversity. OBSERVATIONS (1) The clinical macroscopic scoring we propose for hair density was significantly correlated with Hamilton classifica...

We herein report a case of hair follicle nevus, a rare hamartoma found on the face and showing follicular differentiation, which was associated with sebaceous hyperplasia. Dermoscopy of the lesion showed yellow globules surrounded by crown vessels/telangiectasias and scattered tiny hairs. Histopathological investigation revealed hyperplasia of the sebaceous glands and proliferation of well-diff...

BACKGROUND Lichen planopilaris (LPP) is an inflammatory disease characterized by a lymphomononuclear infiltrate surrounding the isthmus and infundibulum of the hair follicle of the scalp, that evolves into atrophic/scarring alopecia. In the active phase of the disease hairs are easily plucked with anagen-like hair-roots. In this study we focused on the expression of integrins and basement membr...

Murine hair follicle morphogenesis gives rise to four distinct pelage follicle types that produce hair shafts differing in length, the number of medulla columns, and the presence and number of bends. Recently, Igfbp5 was identified as the first molecular marker that distinguishes among different hair follicle types and shown to mark zigzag hairs. Further, it was demonstrated that Igfbp5 express...

Thymosin beta4, a 43-amino acid polypeptide that is an important mediator of cell migration and differentiation, also promotes angiogenesis and wound healing. Here, we report that thymosin beta4 stimulates hair growth in normal rats and mice. A specific subset of hair follicular keratinocytes in mouse skin expresses thymosin beta4 in a highly coordinated manner during the hair growth cycle. The...

The last ten years has revealed some of the key players in the development and differentiation of the hair follicle and the epidermis in general. In this review, we discuss how our current understanding of these processes has been made possible by the elucidation of the molecular basis of human inherited diseases and mouse mutants which display defects in the hair and epidermis. For examples, t...

The location of follicular and epidermal stem cells in mammalian skin is a crucial issue in cutaneous biology. We demonstrate that hair follicular stem cells, located in the bulge region, can give rise to several cell types of the hair follicle as well as upper follicular cells. Moreover, we devised a double-label technique to show that upper follicular keratinocytes emigrate into the epidermis...

Here, we explore the established and potential roles for intradermal adipose tissue in communication with hair follicle biology. The hair follicle delves deep into the rich dermal macroenvironment as it grows to maturity where it is surrounded by large lipid-filled adipocytes. Intradermal adipocytes regenerate with faster kinetics than other adipose tissue depots and in parallel with the hair c...

Parathyroid hormone (PTH) and parathyroid hormone-related protein (PTHrP) influence hair follicles through paracrine and intracrine routes. There is significant evidence that PTH and PTHrP influence the proliferation and differentiation of hair follicle cells. The PTH/PTHrP receptor signalling plays an important role in the hair follicle cycle and may induce premature catagen-telogen transition...

We report for the first time the successful maintenance and growth of human hair follicles in vitro. Human anagen hair follicles were isolated by microdissection from human scalp skin. Isolation of the hair follicles was achieved by cutting the follicle at the dermo-subcutaneous fat interface using a scalpel blade. Intact hair follicles were then removed from the fat using watchmakers' forceps....