ABSTRACT
BACKGROUND: The main function of melanocyte is known to protect the skin from hazardous sunlight. But, some investigators have claimed lately that melanocytes are also related to the immunologic role in the epidermis because these cells produce IL-1 activity and IL-1beta convertase activity, in vitro. OBJECTIVE: Our purposes were to investigate the effects of rIFN-gammaon the proliferation of melanocytes, melanin content, and the expression of HLA-DR antigen on melanocytes after a rIFN-gammaexposure. MEHTODS: The number of melanocytes, the melanin content, and the expression of HLA-DR antigen were evaluated on cultured human melanocytes according to a time sequence and various concentrations of rIFN-gamma. RESULTS: Antiproliferative activity on melanocytes was dependent on the exposure time and the concentration of rIFN-gamma. According to the exposure time and the concentration of rIFN-gamma, melanogenic acivity was inhibitd or stimulated. Normal melanocytes didn't express HLA-DR antigen, but when normal melanocytes were exposed to rIFN-gamma, the expression of HLA-DR antigen increased in a time-and concentration-dependent fashion. After the removal of rIFN - gammafrom the culture media, the expression of HLA-DR antigen on melanocytes also disappeared. CONCLUSION: In our study, melanocytes seem to be related to the immunologic role in the epidermis because these cells expressed HLA-DR antigen after rIFN-gammaexposure and we think that study could help to investigate between melanocytes and immunologic mechanisms in various inflammatory skin diseases.