The Role of Lymphocytes in the Development and Treatment of Alopecia Areata

The document from 2015 examines the involvement of lymphocytes, particularly CD8+ cytotoxic T lymphocytes (CTLs), in the pathogenesis of alopecia areata (AA) and explores potential treatment strategies. It underscores the essential role of CD8+ CTLs in the induction and perpetuation of AA, with studies showing that their depletion can lead to hair regrowth in animal models. The paper also discusses the deficient function of regulatory T cells (Tregs) in AA, the role of TH17 cells, and the dysregulation of CTL activation and lymphocyte homeostasis. It suggests that future treatments may target these pathogenic T cell populations and the pathological immune response, with potential strategies including immune checkpoint blockade, cytokine signaling blockade, and promoting immune tolerance through Tregs. The document also reviews the therapeutic use of contact allergens and topical immunosuppressants, and the potential of targeting lymphatic recruitment and promoting T-regulatory cells. Despite the exploration of various treatments, the authors acknowledge the need for further research to fully understand the mechanisms of AA and develop effective treatments.