Vitiligo is a disease which destroys pigments cells, most notably in the skin. A consortium of six universities has initiated a study on the disease. Results indicate that 30-40% of patients with vitiligo have destruction of pigment cells in the choroid pigment epithelium of the eyes. Approximately 7-10% of the patients seen at a major eye clinic have vitiligo. These data suggest vitiligo is responsible for certain inflammatory diseases of the eyes. Lymphocytes of patients with vitiligo are non-reactive against allogeneic melanoma cells, however, lymphocytes from patients with halo nevi are strongly reactive. Patients with vitiligo do not have anti-pigment cell antibodies in their blood although three of seven patients with mucocutaneous candidasis without vitiligo have antibodies. We have developed a method to quantify Langerhan cells in epidermal sheets. Psoralens and UVA (320 - 400 nm) deplete the skin of Langerhan cells but not short wave ultraviolet light(250-320nm).