Emerging role of regulatory T cells in the immunopathogenesis of vitiligo and implications for treatment

Vitiligo is an autoimmune skin disease that targets pigment-producing melanocytes and results in depigmentation. This disfiguring condition frequently affects visible areas of the body and therefore causes a heavy psychological burden and a decreased quality of life. Although it remains intractable, the ever-growing understanding of its immunopathogenesis has dramatically shaped the treatment paradigm for vitiligo. With the impact of autoreactive cytotoxic T cells explained extensively, accumulating evidence suggests the unique role of regulatory T cells (Tregs) in the immune microenvironment of vitiligo. We systematically reviewed Treg deficiency, instability, reduced vitality and dysfunction in people with vitiligo, combined with novel findings regarding Treg function modulation in autoimmune backgrounds, including metabolic alteration, post-translational modifications and interaction with other immune cells. We further summarized classic and advanced Treg-targeted therapeutics in vitiligo practice and research. Herein, we share up-to-date knowledge of Tregs in vitiligo, providing insights into novel Treg-based therapeutic strategies.