I will establish a culture system to isolate and grow the normal precursors of melanocytes ( pigment cells ) from human foetal skin of different ages, by adaptation of a system for murine melanoblasts recently developed in the host laboratory.
I will characterise the markers expressed by the resulting cells by Northern and Western blotting and immunocytochemistry, to determine whether there is one or more than one discrete type of precursor or melanoblast. The effects of individual components and additives in the cultures on the growth and differentiation of these cells will be analysed. These cultures will have many uses related to human pigmentary diseases. A priority will be to examine certain apparently melanoma-specific properties or markers to see whether they are shared with precursor cells. These markers will include the anti-melanoma antibodies of A. Houghton et al., suggested to identify developmentally early and intermediate subsets of melanomas.