Differential lectin binding to mammalian keratinocytes and melanocytes in vitro
Schuler, G.; Romani, N.; Fritsch, P.O.
European Journal of Cell Biology 27(1): 88-95
1982
ISSN/ISBN: 0171-9335 PMID: 7084255 Document Number: 184201
Guinea pig melanocytes and keratinocytes in primary mixed epidermal cell cultures were investigated as to their differential lectin binding capacities. Cultures were exposed to a battery of fluorescent (FITC -labeled lectins for a 1 step technique and biotinylated lectins followed by avidin-HRP in a 2 step technique). Most of the lectins bound to both melanocytes and keratinocytes. Lectins with specificity for N-acetyl-galactosamine and terminal D-galactose bound only to keratinocytes; melanocytes were reactive, however, at contact sites of dendrites with keratinocyte cell bodies. Ulex europaeus (specific for L-fucose) bound to neither melanocytes nor keratinocytes. Neuraminidase pretreatment restored the capacity of melanocytes to bind all lectins except U. europaeus. In melanocytes, receptor sites for N-acetyl-galactosamine and terminal D-galactose are masked by sialic acid residues; they appear to emerge under conditions of cell-to-cell contact as in the course of pigment transfer. Masking and demasking processes may therefore bear a functional significance.