Cellular Localization of Lectin-affinity in Tissue Sections of Normal Human Duodenum

Peroxidase (HRP) conjugates of Arachis hypogaea agglutinin (PNA), Dolichos biflorus agglutinin (DBA), Ulex europaeus agglutinin I (UEA I) and Bandeiraea simplicifolia agglutinin I (BSA I) were used to detect the expression of carbohydrate moieties in glyco-conjugates of normal human duodenal mucosa. Lectin histology was performed on sections from paraffin embedded specimens of donor blood groups A, B, AB and 0. While PNA, DBA and UEA I staining appeared to be independent of the donor blood groups, BSA I affinity was restricted to the blood groups B and AB. Neither striated columnar cells nor goblet cells stained with PNA-HRP conjugates. Glyco-conjugates of goblet cell mucins reacted with DBA and UEA I, but staining intensities varied in crypts and villi: positive goblet cells occurred preferentially in upper parts of the crypts and in villi. Striated columnar cells also exhibited variation in staining intensities, with binding of DBA and UEA I observed in the upper half of crypts and in villi, occurring predominantly along the brush border and in apical parts of the cells. Glyco-conjugates synthesized by Brunner's gland cells possessed a great variety of lectin reactivity with the lectins employed. Within a given histological section positive gland areas with different staining intensities beside negative cell populations might reflect different functional states.