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1.
Biotinylated lectins were used to investigate the expression of carbohydrate residues on columnar and squamous epithelium of the uterine cervix. Con A, WGA, RCA I, PNA, UEA I, DBA and SBA were used. In the native exocervical and in metaplastic squamous epithelium of the transformation zone, one group of lectins (Con A, WGA, RCA I and PNA) stained the cell periphery of all epithelial layers. A second group (UEA I, DBA and SBA) colored the cell periphery of the suprabasal cells. The basal layer was always negative. All lectins labeled the apical border and occasionally the cytoplasm of the endocervical columnar epithelium. Lectin-binding of metaplastic and native squamous epithelium could possibly be used as a marker of epithelial differentiation in normal and abnormal conditions.  相似文献   

2.
M Nakai  Y Tatemoto  H Mori  M Mori 《Histochemistry》1985,83(5):455-463
The lectin-binding patterns of the cells involved in amelogenesis and dentinogenesis in developing teeth of rats were studied. Undifferentiated odontogenic epithelia exhibited very slight staining with almost all of the lectins examined. The lectin-staining affinities of secretory ameloblasts could be divided into two categories: Concanavalin-A (Con-A), Wheat germ agglutinin (WGA) and Soybean agglutinin (SBA) binding occurred from the middle to apical cytoplasm, whereas Ricinus communis agglutinin-I (RCA-I) and Ulex europeus I (UEA-I) binding predominated in the basal regions. The cells of the stratum intermedium exhibited relatively strange lectin staining, which appeared to be dependent on ameloblastic maturation. The basement membranes in undifferentiated epithelia were markedly positive for lectin binding. Odontoblasts showed moderate Con-A staining on the apical side of the cells, as well as slight-to-moderate reactions with WGA and SBA. Pulp cells and dental papillae showed slight-to-moderate lectin staining, and predentin and dentin were also moderately positive for Con-A and RCA-I binding and slightly so for WGA and SBA. The lectin-binding affinities were enhanced during the formation of enamel and dentin, and appeared to be dependent on the degree of cellular differentiation in ameloblasts and odontoblasts.  相似文献   

3.
Summary The lectin-binding patterns of the cells involved in amelogenesis and dentinogenesis in developing teeth of rats, were studied. Undifferentiated odontogenic epithelia exhibited very slight staining with almost all of the lectins examined. The lectin-staining affinities of secretory ameloblasts could be divided into two categories: Concanavalin-A (Con-A), Wheat germ agglutinin (WGA) and Soybean agglutinin (SBA) binding occurred from the middle to apical cytoplasm, whereas Ricinus communis agglutinin-I (RCA-I) and Ulex europeus I (UEA-I) binding predominated in the basal regions. The cells of the stratum intermedium exhibited relatively stranges lectin staining, which appeared to be dependent on ameloblastic maturation. The basement membranes in undifferentiated epithelia were markedly positive for lectin binding. Odontoblasts showed moderate Con-A staining on the apical side of the cells, as well as slight-to-moderate reactions with WGA and SBA. Pulp cells and dental papillae showed slight-to-moderate lectin staining, and predentin and dentin were also moderately positive for Con-A and RCA-I binding and slightly so for WGA and SBA. The lectin-binding affinities were enhanced during the formation of enamel and dentin, and appeared to be dependent on the degree of cellular differentiation in ameloblasts and odontoblasts.  相似文献   

4.
Immunohistochemical demonstration of S-100 protein in Langerhans cells (LCs) was made in odontogenic epithelial tumours (71 cases), radicular cysts (40 cases), follicular cysts (28 cases), odontogenic keratocysts (11 cases), primordial cysts (7 cases) and fissual cysts (6 cases). With the use of polyclonal antiserum against S-100 protein, positive LCs, dendrical or irregular in shape were found in tumour or cystic epithelia, and sometimes in stromal connective tissue. Incidence of positive S-100 staining LCs was 11 cases out of 61 ameloblastomas, 22 cases out of 40 radicular cysts, 3 cases of 28 follicular cysts, and other lesions in both odontogenic tumours and cystic diseases lacked LCs. The cases with S-100 protein positive LCs were usually accompanied with a high degree of inflammatory infiltration in their lesions; on the contrary, the negative cases also generally lacked inflammatory responses.  相似文献   

5.
The digestive tract of the tortoise Testudo graeca (Testudines) was investigated by means of light and electron microscopy. The esophagus of T. graeca was lined by two types of epithelium: non-keratinized stratified squamous in the upper portion and stratified columnar in the lower. The lamina propria of the esophagus contained tubular or tubuloacinar glands. The mucosa of the stomach showed similar characteristics to those of other reptiles. The small intestine exhibited longitudinal folds lined by absorptive and goblet cells. The large intestine was lined by columnar mucous cells. Within the lamina propria of the large intestine, masses of 10–15 epithelial cells connecting with the surface epithelium by means of slender cytoplasmic processes were observed. A battery of six lectins (Con-A, PNA, WGA, DBA, SBA, and LTA) was used to identify the epithelial mucins. WGA and DBA reacted with all types of mucous cells throughout the alimentary canal. PNA was only unreactive in the intestine, LTA in the esophagus, and SBA in the large intestine. These results indicate a similar lectin-binding pattern throughout the gut of T. graeca.  相似文献   

6.
S Geleff  P B?ck 《Histochemistry》1984,81(6):543-549
Complex carbohydrate components of secretory granules and the glycocalix were analysed in surface epithelia, endoepithelial glands and exoepithelial tubuloalveolar glands of the biliary-ductular system (guinea pig). Brunner glands and pyloric glands were studied for comparison. The columnar epithelial cells of the gallbladder and biliary ducts displayed a well-developed PAS-positive apical glycocalix. These materials strongly bound Ricinus communis A I, Ulex europaeus I, Lotus tetragonolobus A and wheat-germ-A lectins. With the exception of Lotus A lectin which did not bind at all, the same lectins stained the basolateral cell surface. The secretory granules in the supranuclear regions of surface epithelia and in the exoepithelial glands strongly bound Ricinus A I, Ulex europaeus I, wheat-germ-A and Helix pomatia lectins. Concanavalin A was less intensively bound by the secretions of tubuloalveolar glands than by the secretory granules in surface epithelia. The luminal and basolateral cell surfaces of glandular cells in the exoepithelial glands were stained by the same spectrum of lectins as were the columnar cells of surface epithelia, but the staining was less distinct. In the guinea pig, the lectin-binding patterns of tubuloalveolar glands in the biliary ducts closely resembled those of Brunner glands and pyloric glands. The secretions of the tubuloalveolar glands were different from the secretion of surface epithelia, as they bound Concanavalin A less intensively.  相似文献   

7.
Collagenase-3 (matrix metalloproteinase-13) is a metalloproteinase (MMP) that is associated with bone lesions and exhibits variable expression patterns in odontogenic cysts; it may play a role in regulating focal proliferation and maturation of jaw cyst epithelium. We studied the localization, staining intensity and distribution of collagenase-3 in 13 periapical granulomas with epithelium, 16 periapical granulomas without epithelium and 10 radicular cysts using archived formalin fixed, paraffin embedded tissues. A monoclonal antibody against human collagenase-3 was used to evaluate its expression. Immunohistochemical staining intensities of collagenase-3 in all periapical lesions were (?), 4 (10%); (+), 1 (3%); (++), 22 (56%) and (+++), 12 (31%); differences were not statistically significant. Immunohistochemical distribution of collagenase-3 in epithelial cells was (?), 17 (44%); (+), 17 (44%); (++), 5 (13%); in fibroblasts it was (?), 8 (20%); (+), 23 (59%); (++), 8 (21%); in plasma cells it was (?), 7 (18%); (+), 22 (56%); (++), 10 (26%); in macrophages it was (?), 7 (18%); (+), and 15 (38%); and (++), 17 (44%). Statistically significant differences were found in epithelial cells (p = 0.00) and fibroblasts (p = 0.02), whereas differences were not statistically significant for plasma cells and macrophages. Collagenase-3 may play a role in the conversion of a periapical granuloma with epithelium to radicular cyst. MMP's influence not only epithelial rest cell migration, but also invasion of various stromal cells into granulomatous tissue.  相似文献   

8.
Single-layered epithelia are the first differentiated cell types to develop in the embryo, with columnar and squamous types appearing immediately after blastocyst implantation. Here, we show that mouse embryonic stem cells seeded on hensin or laminin, but not fibronectin or collagen type IV, formed hemispheric epithelial structures whose outermost layer terminally differentiated to an epithelium that resembled the visceral endoderm. Hensin induced columnar epithelia, whereas laminin formed squamous epithelia. At the egg cylinder stage, the distal visceral endoderm is columnar, and these cells begin to migrate anteriorly to create the anterior visceral endoderm, which assumes a squamous shape. Hensin expression coincided with the dynamic appearance and disappearance of columnar cells at the egg cylinder stage of the embryo. These expression patterns, and the fact that hensin null embryos (and those already reported for laminin) die at the onset of egg cylinder formation, support the view that hensin and laminin are required for terminal differentiation of columnar and squamous epithelial phenotypes during early embryogenesis.  相似文献   

9.
10.
The lining of the trachea consists of a pseudostratified, mucociliary epithelium that under a variety of conditions, such as vitamin A deficiency, toxic and mechanical injury, becomes a stratified squamous epithelium. Several in vitro cell culture models have been established to study the process of differentiation of airway epithelium. Such studies have indicated that mucosecretory differentiation of tracheal epithelial cells can be modulated by substratum. This study was undertaken to understand molecular mechanisms of squamous differentiation in tracheal epithelia. Primary cultured tracheal cells grown on uncoated filters were differentiated to single layer of squamous cells, whereas cells were grown as stratified columnar cells on collagen-I coated filters. The responses to secretagogues were altered according to culture conditions. DD-PCR revealed that FAK and a WD protein expression was increased in squamous tracheal epithelia. Expression of a WD protein was changed by the treatment of retinoic acid in various epithelial cells. These results indicated that squamous differentiation of tracheal cells changes the expression of a variety of genes, and that the experimental model for this study can be employed to study molecular mechanisms of squamous differentiation in airway epithelial cells.  相似文献   

11.
Search for the presence of lectin-binding sites on Toxoplasma gondii   总被引:4,自引:0,他引:4  
Evidence for the presence of carbohydrate on the surface membrane of Toxoplasma gondii trophozoites and on the cell wall of toxoplasma brain cysts was sought by fluorescent lectin staining. Using FITC-conjugated preparations of Concanavalin A (Con A), wheat germ agglutinin (WGA), or soy bean agglutinin (SBA), we have failed to obtain evidence for the binding of these lectins on the surface of T. gondii trophozoites. In contrast, the three test lectins bound effectively and specifically to the wall of toxoplasma brain cysts. Prefixation of cysts with glutaraldehyde or brief trypsinization of cysts did not affect the intensity of cyst wall fluorescence when stained with FITC-conjugated Con A, SBA, or WGA. The results are interpreted to indicate that whereas exposed Con A, SBA, and WGA binding sites are associated with the wall of toxoplasma brain cysts, such lectin-binding saccharide residues are not present on the surface of trophozoites in exposed or reactive form.  相似文献   

12.
Toll-like receptors (TLR) are essential for the innate immune response against invading pathogens and have been described in immunocompetent cells of areas affected by periapical disease. Besides initiating the inflammatory response, they also directly regulate epithelial cell proliferation and survival in a variety of settings. This study evaluates the in situ expression of TLR4 in periapical granulomas (PG) and radicular cysts, focusing on the epithelial compartment.Twenty-one periapical cysts (PC) and 10 PG were analyzed; 7 dentigerous non-inflamed follicular cyst (DC) served as control. TLR4 expression was assessed by immunohistochemistry. TLR4 immunoreaction products were detected in the epithelium of all specimens, with a higher percentage of immunostained cells in PG. Although TLR4 overexpression was detected in both PG and PC, there were differences that seemed to be related to the nature of the lesion, since in PG all epithelial cells of strands, islands and trabeculae were strongly immunoreactive for TLR4, whereas in PC only some areas of the basal and suprabasal epithelial layers were immunostained. This staining pattern is consistent with the action of TLR4: in PG it could promote formation of epithelial cell rests of Malassez and in epithelial strands and islands the enhancement of cell survival, proliferation and migration, whereas in PC TLR4 could protect the lining epithelium from extensive apoptosis. These findings go some way towards answering the intriguing question of why many epithelial strands or islands in PG and the lining epithelium of apical cysts regress after non-surgical endodontic therapy, and suggest that TLR4 plays a key role in the pathobiology of the inflammatory process related to periapical disease.Key words: TLR4, periapical inflammatory granulomas, radicular cysts  相似文献   

13.
凝集素受体在外阴良、恶性肿瘤中的表达   总被引:1,自引:0,他引:1  
目的探讨细胞表面糖基的变化与外阴表皮细胞良性或恶性增殖的关系。方法采用链霉素抗生物素-过氧化物酶组织化学技术,应用12种凝集素研究60例外阴良、恶性疾病中细胞膜糖基的表达和分布情况。结果从正常外阴表皮到外阴鳞状细胞癌凝集素MPA,ConA,WGA和RCA表达分布无明显的变化。凝集素DBA,LTA和SBA表达均阴性。仅凝集素UEA-1,PNA,VVA,DSA和HPA的表达发生改变。在正常外阴表皮的基底细胞UEA-1,PNA和HPA染色呈阴性,而在外阴鳞状细胞癌出现UEA-1和PNA的阳性表达。在外阴正常表皮VVA和DSA均无表达,但在外阴鳞状细胞增生,外阴尖锐湿疣和外阴鳞状细胞癌中出现不同程度和分布的表达。结论岩澡糖是外阴角朊细胞终末分化的一种标志物;乙酰氨基半乳糖(GalNAc)残基随着外阴表皮细胞的分化而逐渐出现;在外阴细胞恶性转化过程中出现Tn和T抗原的表达;凝集素UEA,VVA,PNA和HPA是外阴表皮良性或恶性增殖的一种好的组织标志物。  相似文献   

14.
Summary The cell surface carbohydrate profile of formalin-fixed paraffin-embedded tissue sections of neoplastic cervical squamous epithelium was evaluated using lectins ofBauhinia purpurea (BPA),Canavalin ensiformis (Con A),Griffonia simplicifolia I (GS I),Griffonia simplicifolia II (GS II),Maclura pomifera (MPA),Archis hypogaea (PNA),Glycine max (SBA),Ulex europaeus I (UEA I) andTriticum vulgaris (WGA). Three lectins (BPA, Con A and PNA) showed a similar pattern of staining in both normal squamous epithelium and in cervical intraepithelial neoplasia (CIN). Variable alterations were seen in lectin-binding patterns in CIN with seven lectins (GS I, GS II, MPA, PNA, SBA, UEA I and WGA). A significant difference was seen between the intensity of staining of normal squamous epithelium and CIN with all lectins except WGA. The alteration in GS II-binding pattern and intensity was significantly related to grade of CIN. No correlation was found between lectin binding and the presence of koilocytes in squamous epithelium. Cases of invasive squamous carcinoma showed a heterogeneous lectin-binding pattern and no siginificant association was found between lectin binding and tumour differentiation or patient survival. These results indicate that neoplasia in cervical squamous epithelium is associated with alterations in terminal -Man residues, - and -GalNAc residues, - and -GlcNAc residues, - and -Gal residues, and -Fuc-containing residues, present in the outer parts of bothN-linked andO-linked glycoconjugates. The implications of these findings are discussed.  相似文献   

15.
Cytoplasmic filaments have been studied extensively by electron microscopy, but the histochemical nature of such fibrils in non-keratinizing epithelia has not been systematically investigated. During studies of early arterial lesions we observed structures with the staining properties of myosins in epithelial cells of various organs. The configurational staining, polarization and fluorescence microscopic properties of these myoid structures were compared with those of myofibrils in smooth muscle and classical myoepithelial cells. The following structures showed the characteristics of myofibrils: the terminal web in columnar epithelial cells of intestine, trachea, bronchi, bile ducts, pancreatic ducts and ductus epididymidis, the pericanalicular layer of bile and pancreatic canaliculi, fibers in the caudal tube of spermatids and the flagella of spermatozoa. Cilia, e.g. of respiratory epithelium, tonofibrils in squamous epithelium and nerve axons did not react. These studies indicate significant histochemical differences between cytoplasmic filaments. Different types of intracellular fibrils can be found in the same cell, e.g. in respiratory epithelium.  相似文献   

16.
Summary The pattern of lectin binding in normal human labial mucosa was examined by light and electron microscopy using eight different lectins (ConA, LCA, WGA, UEA-1, RCA-1, SBA, DBA and PNA) and compared with the patterns in normal human skin and oesophageal mucosa. As seen by light microscopy, ConA, LCA, and WGA stained cell membranes in all layers of the mucosae. RCA-1 stained the plasma membrane of cells in the basal and middle layers, whereas cells in the superficial layers showed little positive staining. UEA-1, SBA, and PNA stained the cells in the middle layers weakly in some cases. No positive staining for DBA was seen. By electron microscopy, reaction product indicating ConA-binding sites was observed in the plasma membrane, cisternae of the endoplasmic reticulum, nuclear envelope and the Golgi apparatus. Binding of LCA, WGA, and RCA-1 was observed in the plasma membrane. These results show that the binding pattern of PNA, SBA, and RCA-1 in labial mucosa is different from that in the normal skin or oesophageal mucosa, although the labial mucosal epithelium, epidermis, and oesophageal epithelium are all stratified squamous epithelia. These differences in the cell-surface sugar residues are likely to be related to the possible functional differences in these tissues.  相似文献   

17.
Glycosylated structures on the cell surface have a role in cell adhesion, migration, and proliferation. Repair of the airway epithelium after injury requires each of these processes, but the normal cell surface glycosylation of non-mucin producing airway epithelial cells is unknown. We examined cell surface glycosylation in human airway epithelial cells in tissue sections and in human airway epithelial cell lines in culture. Thirty-eight lectin probes were used to determine specific carbohydrate residues by lectin-histochemistry. Galactose or galactosamine-specific lectins labeled basal epithelial cells, lectins specific for several different carbohydrate structures bound columnar epithelial cells, and fucose-specific lectins labeled all airway epithelial cells. The epithelial cell lines 1HAEo– and 16HBE14o– bound lectins that were specific to basal epithelial cells. Flow cytometry of these cell lines with selected lectins demonstrated that lectin binding was to cell surface carbohydrates, and revealed possible hidden tissue antigens on dispersed cultured cells. We demonstrate specific lectin-binding patterns on the surface of normal human airway epithelial cells. The expression of specific carbohydrate residues may be useful to type epithelial cells and as a tool to examine cell events involved in epithelial repair.  相似文献   

18.
Summary Lectins ofBauhinia purpurea (BPA),Canavalin ensiformis (Con A),Griffonia simplicifolia I (GS I),Griffonia simplicifolia II (GS II),Maclura pomifera (MPA),Arachis hypogaea (PNA),Glycine max (SBA),Ulex europaeus I (UEA I) andTriticum vulgaris (WGA) were used to evaluate cell surface carbohydrates in formalin-fixed paraffin-embedded tissue sections of normal human cervix uteri. Consistent patterns of staining of the squamous epithelium were obtained in all 30 cases with BPA, GS II, MPA, PNA, SBA and WGA. A variable distribution of lectin binding was seen in squamous epithelium with Con A, GS I and UEA I. The patterns of GS I and GS II binding reflected squamous epithelial maturation. Columnar epithelium did not stain with GS II, stained variably with Con A, and stained consistently with the remaining seven lectins in all cases. No association between lectin binding and blood group or phase of the menstrual cycle was found. These findings may be used as a baseline for evaluation of lectin binding in both preinvasive and invasive lesions of the cervix uteri.  相似文献   

19.
Immunoelectron microscopy was combined with partial characterization of isolated exopolysaccharide to study binding of soybean lectin by Rhizobium japonicum strain USDA 138. Lectin-binding activity resided in two forms of exopolysaccharide produced during growth: an apparently very high-molecular-weight capsular form and a lower-molecular-weight diffusible form. At low-speed centrifugation, the capsular form cosedimented with cells to form a viscous, white, cell-gel complex which was not diffusible in 1% agar, and the diffusible form remained in the cell-free supernatant. Electron microscopic observation of the cell-gel complex after labeling with soybean lectin-ferritin conjugate revealed that capsular polysaccharides, frequently attached to one end of the cells, were receptors for lectin. The outer membrane of the cell bound no lectin. Various preparations of exopolysaccharide isolated from the culture supernatant were tested for lectin binding, interaction with homologous somatic antigen, and the presence of 2-keto-3-deoxyoctonate and were chromatographed in Sepharose 4B and 6B gel beds. Lectin binding was restricted to a polysaccharide component designated as lectin-binding polysaccharide. This polysaccharide, as present in the cell-free culture supernatant, was a diffusible acidic polysaccharide devoid of 2-keto-3-deoxyoctonate, with a molecular weight of 2 X 10(6) to 5 X 10(6). It was concluded that the soybean lectin-binding component of R. japonicum is an extracellular polysaccharide and not a lipopolysaccharide and that the diffusible lectin-binding polysaccharide probably differs from the very high-molecular-weight lectin-binding polysaccharide of the loose capsule (slime) only in the degree of polymerization.  相似文献   

20.
Cyst structures were often detected in and around thyroid glands of the dog. The present study revealed the frequency of occurrence, the light microscopic features, and the immunoperoxidase reactions to anti-keratin and anti-19S-thyroglobulin antisera of each cyst located in parathyroid III, parathyroid IV, thymus IV, C-cell complexes, and thyroid parenchyma from 112 dogs. In each location, cysts showed characteristic features. In parathyroid III, the cysts were covered with single or pseudostratified epithelium composed of ciliated cells; whereas in parathyroid IV they were covered with keratinizing stratified squamous epithelium. In C-cell complexes, small cysts lined with small packed cells were predominant, and large cysts lined with single cuboidal cells or stratified squamous cells were also present. In thymus IV located in the close vicinity of parathyroid IV, cyst epithelium consisted of several types of cells showing variable features. In thyroid parenchyma, there were several types of cysts: some were covered with ciliated columnar cells, and others were covered with two or multilayers of small packed cells or cuboidal cells. In spite of these differences in appearance of the cysts located in different tissues, all their epithelia were immunoreactive to the keratin antisera, except for small cysts in C-cell complexes, which were regarded as immature structures. Thus, the presence of keratin filaments in epithelial cells seems to be a characteristic feature of all cysts. The lumens of each cyst contained variable amounts of amorphous materials, which showed colloid-like, flocculent, foamy, and granular features and were periodic acid-Schiff-positive in variable degrees, from weak to intense. Although the lumenal contents of the cysts in parathyroid III revealed no immunoreactivity for 19S-thyroglobulin, those in thyroid parenchyma, C-cell complexes, parathyroid IV, and thymus IV reacted strongly with the 19S-thyroglobulin antiserum.  相似文献   

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