Observational Studies On Visual Evidence Of Melanocytes Exocytosis

Background:It is well known that melanosomes are secreted from melanocytes and uptaken by keratinocites surroundings in human skin tissue. Different colors of skin are depend on how much melanosomes secreted and uptaken. At present, the machanism of the secretion of melanosomes from melanocytes is not yet clear. However, it is sure that the secretion of melanosomes will cause the microchanges of the surface morpholagy of melanocytes. Therefore, we ulitied AFM and ESEM which are on good effected for observing the surface of cells to observe and analysis melanosomes thransfer.Objective:Melanosomes exocytosis and thransfer induced changes of cell morphology, and it is known that AFM and ESEM could observe the nanoneter lever morphology changes.Therefor, we use AFM and ESEM observe melanocytes exocytosis melanosomes and acquisit the image evidences. To evidence the melanocytes exocytosis process is the major function of melonosome thransfer by analysising the pit structures and viscles changes on the surface of melanocytes.Methods:Purified melanocytes and KC from foreskin, and cultured the MCs for 5 groups which were the control group, α-MSH group, PGE2 stimulation group, and co-culture KC group. After culture and stimulate the cells for 2 days, we fixed them using glutaradehyde. Making the examples for observation of AFM and ESEM. Then,respectively collection the cell surface morphology data in AFM and ESEM. Finally,the data were analyzed using statistical software.Results:Purified the melanocytes and keratinocytes, and MCs surface revealed vesicles and pockmark structures observed by AFM and ESEM. After stimulated by α-MSH,PGE2, or co-cultured with KCs for 2 days, observed by ESEM, vesicles and pockmark like structure were obvious increased. We also displayed that vesicles sturring on the dendrites and would shedding off from the dendrites.Conclusion:According to our results, secretion and translocation of melanosomes were major via exocytosising of vesicles and formation of pockmarks like structures in the surface of melanocytes. It provides an direct image evidence that absorved by AFM and ESEM.