Ultrastructural localization of lectin-binding sites in normal human eccrine and apocrine glands

Abstract

The distribution of carbohydrate residues in eccrine and apocrine glands of normal human skin was studied using a post-embedding technique with Lowicryl K4M. Thin sections were incubated with Ulex europaeus agglutinin I (UEA I), wheat germ agglutinin (WGA), peanut agglutinin (PNA), concanavalin A (Con A), soybean agglutinin (SBA), and dolichos biflorus agglutinin (DBA). All lectins except for PNA showed labeling of the plasma membranes of dark cells, clear cells, and apocrine cells. The granules of the eccrine gland were labeled with all lectins except for DBA. The mitochondrial granules of the apocrine gland were not labeled with any lectin, whereas the lysosomal granules showed a positive reaction with all lectins except for PNA. After incubation with PNA, in eccrine glands the granules were the only structure labeled, whereas in apocrine glands the luminal side of the plasma membrane and cytoplasmic vesicles beneath it were the only structures labeled.