Fine structure of the nevus cell

Abstract

The purpose of this investigation was to characterize the fine structure of the nevus cell and to demonstrate, if possible, a unique premelanin granule. The presence of this granule in the nevus cell would substantiate the relationship between the nevus cell and the melanocyte. Biopsy specimens of dermal nevi with and without untra-violet light stimulation were studied with an electron microscope and the following conclusions were reached: (1) The fine structure of the nevus cell is comparable to that of the melanocyte. (2) The premelanin granule or melanosome is present in the nevus cell, particularly after prolonged ultraviolet light stimulation. (3) The nevus cell is probably an embryonal cell that can differentiate with appropriate stimuli.