Updates in the Pathogenesis of Alopecia Areata

The document from April 2021 discusses alopecia areata, an autoimmune disorder that leads to non-scarring hair loss and can significantly affect patients' mental health. The pathogenesis of alopecia areata is believed to involve the collapse of the immune privilege of hair follicles, which may be triggered by a disturbance within the follicle environment or by a dysregulated central immune system. Genetic factors are implicated, with several gene loci identified in association with the condition. Key immune players in the disease process include autoreactive effector T cells, NKG2D+ CD8+ cytotoxic T cells, NK cells, the JAK/STAT pathway, MICA, IFN‐γ, and IL-15. Currently, there is no accepted cure for alopecia areata, and treatment responses are unpredictable. Understanding the precise pathogenic mechanisms is crucial for developing targeted therapies.