Lectin-Binding Patterns in the Microenvironment of the Mouse Developing T-Cells

Glycoconjugates and their programmed changes during the course of development in the cell-surface as well as in the extracellular matrix, are known to affect cell differentiation, cellular interaction and other developmental phenomena during embryogenesis. The purpose of this study was to localize N-acetylgalactosamin as well as fucose-containing glycoconjugates in situ during thymus development. Staged embryos or thoracic segments were fixed and processed for lectin histochemistry studies. Five microns paraffin-embedded sections were incubated with horseradish peroxidase conjugated lectins from Dolichos biflorus and Aleuria aurantia specific for N-acetylgalactosamine and fucose, respectively. Our results revealed unique reaction of T-cells with Dolichos biflorus and the presence of a fucosylated glycoconjugate in microenvironments of the developing thymus including extracellular matrix and developing Hassall bodies. The time and distribution of staining with these two lectins suggest that fucosylated glycoconjugates and N-acetylgalactosamin terminal sugars may play significant role in intrathymic microenvironment that might cause differentiation of T-lymphocytes