Cutaneous histiocytosis X. The presence of S-100 protein and its use in diagnosis

Abstract

The cellular localization of glial S-100 protein was investigated in paraffin-embedded sections of [human] cutaneous histiocytosis X and in a variety of cutaneous infiltrative disorders, including juvenile xanthogranuloma, necrobiotic xanthogranuloma, papular xanthoma, eruptive histiocytoma and reticulohistiocytosis. Immunoperoxidase staining with a rabbit anti-calf brain-S-100 antibody demonstrated strong and consistent activity in atypical histiocytes in all histiocytosis X specimens. No detectable S-100 protein was demonstrated in histiocytes or giant cells in the non-X histiocytic disorders investigated. Positive controls were included within both groups of disorders in respect to melanocyte, epidermal Langerhans'' cell, and dermal Schwann''s cell staining. There is diversity in the mononuclear phagocyte system. Such a simple test is practical in diagnostic problems involving infiltrative histiocytic disorders of the skin.