The immunology of vitiligo

Vitiligo is an autoimmune disease of melanocyte destruction, which manifests as progressive, patchy loss of pigmentation in the skin. As one of most common autoimmune diseases, vitiligo inflicts a significant psychosocial burden. Research over the past two decades has revealed the underlying immune mechanisms of vitiligo, with key studies combining detailed analyses of patient tissue samples with mechanistic experiments in mouse models. Vitiligo has emerged as a prototypical CD8⁺ T cell-mediated autoimmune disease, with cooperation between innate immune cells, dendritic cells, T cells, keratinocytes and fibroblasts driving autoimmune pathology against the uniquely susceptible melanocyte target. The study of vitiligo has also revealed aspects of CD8⁺ T cell memory and resident memory against self-antigens. This work has drawn from, and contributed to, the study of melanoma immunology. Whereas drugs used for other autoimmune conditions have been largely ineffective in treating vitiligo, a growing base of knowledge recently led to the first successful FDA-approved immune-modulating drugs for vitiligo. This review focuses on the immunology of vitiligo: the mechanisms that drive melanocyte destruction, the biology of aberrant T cell responses against melanocytes and therapeutic means for counteracting this autoimmune condition.