Lectin histochemistry of the mast cell: A light microscopical study

The purpose of this study was to determine if human mast cell granules contain non repeating oligosaccharide sequences. The binding of lectins to human mast cell granules was studied using a panel of 11 lectins variously selective for both N- and O-linked oligosaccharide sequences. The tissues were principally derived from cutaneous neurofibromata and benign and malignant breast diseases, that is, readily available human material with a known high content of mast cells. Lectin-binding sites in the formalin-fixed paraffin-embedded or resin-embedded material were visualized by means of biotinylated lectins and an avidin-peroxidase technique for light microscopy. The results indicate that human mast cell granules contain abundant N-linked sequences, but few or no O-linked residues. These sequences appear to be mostly in the form of non-bisected highly branched or smaller biantennate sequences, although variable positive binding with erythrophyto-haemagglutinin was observed, indicating some degree of bisection. © 1988 Chapman and Hall Ltd.