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Ultrastructural localization of blood group antigens in human salivary glands.
No full textThe subcellular distribution of several blood group antigens was studied in human major and minor salivary glands by means of a postembedding immunogold staining method. In each gland, antigens were detected as secretory products and as cell surface components. A, B, H and Lewis (a,b,x,y) antigens were found in mucous cells depending on the ABO and secretor status; reactivities were confined to the secretory granules. In serous and ductal cells, both the secretory granules and cell membranes were reactive, but only for H, Le-b and Le-y irrespective of the ABO and secretor status
An immunohistochemical study of the distribution of ABH antigens in human submandibular glands at the light and electron microscopic levels.
No full textThe distribution of blood group antigens ABH in submandibular glands was studied at light and electron microscopy levels by applying ImmunoGold Silver Staining (IGSS) and post-embedding ImmunoGold (IGS) methods, respectively. In IGSS treated samples, a cytoplasmic and a surface form of antigen localization were discernible in the glandular parenchyma. The former was restricted to most mucous cells and to scattered serous cells: A and B antigens were demonstrated in mucous cells of A and B type glands, while H antigen appeared in most mucous and occasional serous elements regardless of the blood type of donors. The latter appeared as a strong H reactivity on cell surfaces of serous acini and ducts regardless of the patient blood type. The IGS method was applied both on non-osmicated samples embedded in LR White resin and on osmicated, Epon embedded samples. In non-osmicated tissues, antigen labelling was revealed in secretory granules and cell surfaces. Positive secretory granules were found in most mucous cells and occasional serous, intercalated, and striated duct cells. A and B antigens weakly reacted in mucous cells of A and B type glands, respectively, while strong H reactivity was seen in mucous, serous, intercalated and striated duct cells of glands of all types. Surfaces labelled with H antigen were found on both lumenal and basolateral membranes of striated ducts in glands of all types. IGS method applied on osmicated, Epon embedded samples, selectively revealed blood group antigens in secretory granules of serous cells but not in the apical vesicles of striated ductal cells. Cell surfaces were completely unreactive
Epithelial-like cells containing lymphocytes (nurse cells) in human adenoids and tonsils
No full textEpithelial cells filled with lymphocytes (nurse cells, NC), recently described in mouse, rat and human thymus, have been interpreted as mediators of direct contact ('stromal') induced thymocyte maturation. We describe analogous NC in trypsin-dissociated human adenoids and tonsils. NC from these organs show morphological characteristics analogous to those of thymic NC: they appear as large (diameter 30-35 micrometers) elements, containing peripherally situated tonofilament bundles, electrodense mitochondria and some vacuoles. Each NC contains 5-30 intact lymphoid cells, some of which appear in the activated state. NC show neither phagocytic ability, nor ANAE and peroxidase cytochemical reactions. The majority of NC from adenoids and tonsils react with the monoclonal antibody (McAb) OKIa1 (DR w framework) as those from thymus, and 40% of them bind fluorescein-conjugated peanut agglutinin. Some of them also react with the McAb OKT3 (pan-T), OKT9 (transferrin receptors) and OKT10 (immature hematopoietic cells). The presence of NC in adenoids and tonsils suggests that these organs may be involved in some stages of lymphocyte maturation requiring intimate contact with epithelial cells
Ultrastructural localization of glycodelin oligosaccharides Le-x and Le-y in human seminal vesicles by immunogold staining
No full textHisto-blood group antigens Le-x and Le-y are oligosaccharidic terminals that characterize many glycoproteins in the human tissues. In seminal plasma, they are expressed as part of the so-called glycodelin S, which is suggested to regulate sperm capacitation/decapacitation. It has recently been demonstrated that the core protein of glycodelin S is secreted by seminal vesicles. Here we show that epithelial cells of human seminal vesicles also release the Le-x and Le-y antigens. The presence of these substances in secretory material was revealed by means of an immunogold staining method in normal surgical samples. The results suggest that glycodelin S is secreted by seminal vesicles in its finished glycosylated form. Moreover, antigen reactivity was also revealed associated with plasma membranes
Electron microscopic immunogold localization of statherin in human minor salivary glands
No full textIn this study, which supplements a recent article on the localization of statherin in human major salivary glands, we investigated the intracellular distribution of this peptide in minor salivary glands by immunogold cytochemistry at the electron microscopy level. In the lingual serous glands of von Ebner, gold particles were found in serous granules of all secreting cells, indicating that statherin is released through granule exocytosis. In buccal and labial glands, mostly composed of mucous tubuli, statherin reactivity was detected in the serous element, which represents only a small population of the glandular parenchyma. In these serous cells, however, statherin labeling was absent in secretory granules and restricted to small cytoplasmic vesicles near or partially fused with granules. Vesicle labeling could be related to the occurrence of an alternative secretory pathway for statherin in buccal and labial glands
Immunoreactivity of the salivary protein statherin in human male accessory sex glands
No full textBACKGROUND: Statherin is a small phosphoprotein chiefly studied for its protective roles towards teeth and oral tissues. Although generally considered as exclusively secreted by salivary glands, circumstantial evidences suggested that other tissues also produce it. This article first demonstrates statherin immunoreactivity in human prostate and seminal vesicles.
METHODS: Surgical samples of prostate and seminal vesicles were fixed in a mixture of paraformaldehyde and glutaraldehyde, and embedded in Epon resin without previous osmication. Ultrathin sections were treated for the intracellular localization of statherin by means of an immunogold staining method.
RESULTS: Reactive statherin was revealed in secreting cells of both seminal vesicle and prostate epithelia: labeling was found in secretory granules of seminal vesicle cells and in cytoplasmic vesicles of prostatic cells.
CONCLUSIONS: The different staining patterns suggested that the two glands secrete statherin through different pathways
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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