Hair Follicles Modulate Skin Barrier Function

This study reports that sebaceous glands can regenerate after injury through stem cell plasticity, with hair-follicle-derived stem cells replacing sebaceous gland progenitors and playing a crucial role in the regeneration process, which is dependent on FGFR2 signaling and aided by hair growth induction.

This article reviews sebaceous immunobiology and highlights the complex role of sebaceous glands and sebocytes in skin barrier function and inflammation, particularly in acne pathogenesis, but reports no new results.

This study summarizes how the IL-23/IL-17 axis contributes to inflammatory skin diseases like psoriasis and highlights that biologics targeting this pathway, including monoclonal antibodies against IL-23 and IL-17, have shown efficacy in clinical trials for these conditions.

This study reports that during late embryogenesis and early postnatal development, K79-expressing keratinocytes change and die independently of sebaceous glands to form the hair follicle opening, potentially influencing conditions like ingrown hairs or acne.

This study found that EGFR-targeted cancer therapy can cause skin toxicities by disrupting epidermal signaling, allowing microbiota invasion and inflammation, but identified a potential treatment approach using FGF7 or SOS expression to restore barrier integrity.

This study demonstrated that tight junction barriers exist in human hair follicles but are less tight in hair follicle keratinocytes than in interfollicular keratinocytes, highlighting claudin-1's key role in follicle barrier function and growth.

The researchers reported that hair follicle development and commensal microbe colonization promote the accumulation of regulatory T cells in neonatal skin, with the Ccl20-Ccr6 pathway playing a key role in this process.

Nanoparticles can improve drug delivery to hair follicles but struggle to penetrate deeper skin layers.

This study introduced Scd3-Cre mice, which enabled sebocyte-specific manipulation, revealing that sebaceous lipid depletion impaired water repulsion, thermoregulation, and the ocular surface, resembling Meibomian gland dysfunction.

The research found that hair follicle–derived cytokines, particularly IL-15 and IL-7, regulate skin-resident memory T cells and their role in both immune homeostasis and lymphoma in the skin.

This study found that hair follicle and interfollicular epidermis stem cells contribute differently to skin regeneration, with their persistence influenced by factors like spatial constraints and competition moderated by Notch suppression.

This study found that the absence of sebaceous glands may be an early factor in the development of keratosis pilaris, leading to hair shaft and skin barrier abnormalities, independent of filaggrin mutations.

This review explores the infundibulum's role and importance in skin diseases and emphasizes the need for further research into its biology and potential therapeutic targeting, but it presents no new findings.

This study found that prolonged Nrf2 activation in mouse keratinocytes led to enlarged sebaceous glands, hair loss, and cysts, suggesting a role for Nrf2 in conditions like MADISH.

This study found that the creation of hair follicle lumens in mice is driven by the outward migration of keratin 79-positive cells, suggesting a novel mechanism for generating hollow cores in hair follicles.

This review outlines a diagnostic framework for clinicians to distinguish different types of inherited ichthyoses and suggests further testing and treatment strategies, but reports no new clinical results.

In this study, researchers found that mouse hair follicles recruit Langerhans cells by secreting chemokines, acting as key portals for these cells in both mice and humans.

This review discusses the mechanisms and storage of particles in hair follicles and presents no new experimental results, highlighting the need for further research in their safe application in dermatology and cosmetics.

This study suggests that MMP-9 plays a significant role in extracellular matrix remodeling during hair canal formation in mice, as indicated by delayed hair shaft emergence and hair canal development in MMP-9 knockout mice.

This review highlights the need for methodologies to understand and quantify drug penetration into hair follicles as significant drug pathways, noting this area lacks comprehensive articles and reports no new results.

Phospholipase Cδ1 is crucial for normal skin and hair development.

This study found that a nonsense mutation in the Cst6 gene of mice leads to severe skin and hair abnormalities, suggesting that cystatin M/E is crucial for epidermal function and viability.

This study found that cathepsin L deficiency in mice led to significant abnormalities in hair follicle development and cycling, including disrupted hair shaft outgrowth and premature hair growth phase entry.

This study suggests that the harlequin ichthyosis mouse model closely resembles human type 2 harlequin ichthyosis, indicating its potential as a useful model for studying the human condition.