Hair Follicles Modulate Skin Barrier Function

This study explores the role of hair follicles in skin barrier function by examining the effects of deleting the Abca12 gene, crucial for skin integrity. It identifies four ways hair follicles influence the skin barrier: forming a functional barrier, triggering non-cell-autonomous responses in the epidermis, impairing desquamation and sebum release, and causing hair follicle cells to migrate into the epidermis. Deleting Abca12 in the upper hair follicle leads to enlarged sebaceous glands, impaired sebum secretion, and hair loss. Neutralizing IL-17a partially alleviated some disease symptoms, indicating hair follicles are active in maintaining skin health. The study suggests targeting multiple inflammatory pathways may be necessary for treating ichthyosis.