Several forms of hair loss in humans are characterized by the inability of hair follicles to enter the growth phase (anagen) of the hair cycle after being arrested in the resting phase (telogen). Current pharmacologic therapies have been largely unsuccessful in targeting pathways that can be selectively modulated to induce entry into anagen. We show that topical treatment of mouse and human ski...

Mammalian hair growth is cyclic, with hair-producing follicles alternating between active (anagen) and quiescent (telogen) phases. The timing of hair cycles is advanced in prolactin receptor (PRLR) knockout mice, suggesting that prolactin has a role in regulating follicle cycling. In this study, the relationship between profiles of circulating prolactin and the first post-natal hair growth cycl...

Hair follicles (HFs) undergo cycles of growth (anagen), regression (catagen) and relative quiescence (telogen), while dysregulated HF cycling underlies the most common hair disorders. Yet intrinsic, autonomous oscillator mechanism that drives cycle clock (HCC) remains elusive. In this study, we present new evidence Myelin Protein Zero-like 3 (MPZL3)—a multifunctional nuclear-encoded protein loc...

BACKGROUND CD10 and CD34 have been detected in both epithelial and mesenchymal components of anagen human hair follicles. OBJECTIVES To analyse the expression of CD10 and CD34 in human hair follicle development as well as in different phases of the hair cycle. METHODS Fetal and adult hair follicles at different stages of the hair cycle were examined by immunohistochemistry for CD10 and CD34...

Many studies have documented an abnormal cell-mediated immune reaction in alopecia areata (AA) 1 . The key histopatho logic feature of AA is a lymphocytic infiltrate around the lower hair follicle, which may appear in a characteristic “swarm of bees” pattern. The affected hair follicles terminate their anagen phase prematurely and regress via the induction of massive apoptosis of the lower port...

A 5-year-old female, known case of pachyonychia congenita, presented with diffuse hair loss; remaining hairs were easily plucked kinky hairs. Hair samples from patient were investigated using a light microscope. The hairs of the patients were mainly anagen hairs and unlike normal plucked anagen hairs, showed keratinization and cornification of their hair bulbs. No specific hair shaft abnormalit...

Hair follicles undergo cyclic behavior through regression (catagen), rest (telogen), and regeneration (anagen) during postnatal life. The hair cycle transition is strictly regulated by the autonomous and extrinsic molecular environment. However, whether there is a switch controlling catagen-telogen transition remains largely unknown. Here we show that hair follicles cycle from catagen to the ne...

The hair follicle (HF) grows during the anagen phase from precursors in the matrix that give rise to each differentiated HF layer. Little is known about the lineal relationship between these layer-restricted precursors and HF stem cells. To understand how the HF stem cells regenerate the typical anagen organization, we conducted in vivo clonal analysis of key stages of the HF cycle in mice. Une...