Pathogenesis of Alopecia Areata and Vitiligo: Commonalities and Differences

The document explores the pathogenesis of alopecia areata (AA) and vitiligo, highlighting both commonalities and differences. Both are autoimmune diseases involving CD8+ T lymphocytes and elevated IFN-γ signaling. AA is characterized by immune privilege collapse in hair follicles, leading to their targeting by immune cells, while vitiligo involves stress proteins that activate immune responses against melanocytes. Shared mechanisms include oxidative stress, genetic factors, and elevated chemokines like CXCL9 and CXCL10. Despite these similarities, distinct pathways and cellular targets differentiate their pathogenesis, emphasizing the need for targeted treatments.