Immunohistochemical analysis of melanocyte content in different zones of vitiligo lesions using the Melan-A marker.

INTRODUCTION Occurence of vitiligo lesions is caused by the destruction of melanocytes in a ected skin and therefore by the re- duction of pigment melanin content. Questions remain about the presence of residual melanocytes in the depigmented skin and optimal methods of their identi cation. METHODS Skin biopsy samples from 16 patients with non-segmental vitiligo and from 10 healthy volunteers were investigated for Melan-A (A103 clone)+ melanocytes expression by immunohistochemical analysis and for melanin by histochemical studies with section staining by Fontana-Masson method. RESULTS For some patients including those with long-standing disease (up to 40 years) Melan-A+ cells and melanin granules were detected in depigmented skin as indication that the residual melanocytes are preserved in vitiligo lesions. More than three-fold decrease of Melan-A+ melanocytes amount was revealed in perilesional normally pigmented skin of vitiligo patients (P < 0.001) compared with the skin of healthy volunteers. Clinically intact skin involvement in the pathological process should be taken into consideration if local treatment methods are prescribed. CONCLUSION In some vitiligo patients the residual melanocytes are preserved in depigmented skin. Melan-A marker is useful for identi cation of melanocytes in vitiligo patients' skin.