Melanocytes of fetal dermis - studies with anti-HMB-45 antibody.

BACKGROUND

Skin melanocytes are specialized cells located within the basal layer of epidermis and in the hair follicles. They are derivatives of neural crest cells and colonize the epidermis in the first trimester of gestation. How they translocate to epidermis is still not understood. The purpose of our study was to continue existing research on melanocyte origin and differentiation, focused on revealing dermal melanocytes by means of immune labeling.

MATERIAL/METHODS: The studies were performed on 50 human fetuses ranging in age from 3 to 7 months, using immunocytochemical staining of skin samples with anti-HMB-45 antibody.

RESULTS

HMB-45 positive cells were revealed either in the epidermal basal layer and hair follicles or among the mesenchyme cells of developing dermis. The cells discussed were round, oval or longitudinal, and exhibited dendritic process.

CONCLUSIONS

Our results suggest that in the course of melanocyte precursor migration from the site of origin in the neural crest to their final location in epidermal basal layer and within the hair follicles, there is also a dermal stage. Moreover, it is very likely that at this dermal stage melanocyte precursors exhibit a high rate of morphological development.