A Focus on Anti-Tyrosinase Antibodies in Melanoma and Vitiligo

Abstract

Tyrosinase is a copper-containing enzyme, which is essential for melanogenesis and pigmentation. This chapter focuses on a series of studies on antityrosinase antibodies that were detected in sera of patients with melanoma, or vitiligo measured by enzyme-linked immunosorbent assay (ELISA). Vitiligo is considered an autoimmune disorder, in which antimelanocyte autoantibodies develop and destroy the normal melanocytes. Patients with vitiligo were found to have higher antityrosinase antibody titers than melanoma patients. To assess autoimmunity to tyrosinase in the pathogenesis of vitiligo, the titers of antityrosinase antibodies were measured in sera of patients with vitiligo and healthy volunteers. Antityrosinase antibodies were measured by in sera of patients with malignant melanoma, with either metastatic disease or no evidence of disease, in patients with melanoma and associated hypopigmentation (MAH), with vitiligo and in healthy volunteers. In these studies, the results show that patients with MAH have a similar relative optical density (ROD) of antityrosinase antibodies as patients with melanoma, but significantly lower antityrosinase antibody ROD than patients with vitiligo, point to the participation of antityrosinase antibodies in the destruction of melanocytes. Antityrosinase antibodies are absorbed by melanocytes and melanoma cells in all the three situations—melanoma, vitiligo, and MAH. However, since the production of antibodies in vitiligo exceeds that in melanoma or MAH, the antibodies are detected in significantly higher RODs only in vitiligo.