Binding sites of Ulex europaeus-lectin I in human parotid gland. A light-microscopic and ultrastructural study using the immunoperoxidase technique and immunocryoultramicrotomy.
Twenty non-neoplastic parotid glands (removed during neck dissection for regional tumours) were examined for cellular and subcellular binding sites of Ulex europaeus-lectin I (UEA-I), a lectin reported to be specific for alpha-L-fucose. For light microscopy, an extended peroxidase-antiperoxidase method was applied; for the evaluation of the subcellular localization of bound lectin, three of these glands were examined following immunocryoultramicrotomy and staining by the protein A-gold technique. In addition to the known cytoplasmic affinity of UEA-I for capillary endothelium, acinar cells bound the lectin within the cytoplasmic compartment; the number and distribution of stained acinar cells varied among individuals. Furthermore, cytomembrane-bound labelling that occurred most markedly at the luminar surface was observed in striated-duct epithelium. Using the electron microscope, protein A-gold particles were seen in zymogen granules and in Golgi cisternae of serous acinar cells; primary saliva secreted in the lumina exhibited strong labelling; serous acinar cells had binding sites on their cell membranes, striated-duct epithelium had binding sites on its surface membrane and in the vicinity of apical vesicles. Our results show that UEA-I is a useful tool for the study of the structure and functional states of the parotid gland epithelium and its associated pathological alterations.
D006258:Head and Neck Neoplasms / Q000473:pathology / Q000601:surgery; D006801:Humans; D007124:Immunoenzyme Techniques; D037102:Lectins / Q000378:metabolism*; D008854:Microscopy, Electron; D010306:Parotid Gland / Q000276:immunology* / Q000473:pathology / Q000648:ultrastructure; D037121:Plant Lectins; D011975:Receptors, Mitogen / Q000378:metabolism*
D037102:Lectins; D037121:Plant Lectins; D011975:Receptors, Mitogen; C036850:Ulex europaeus lectins