scholarly journals Junctional complexes in epithelial cells: sentinels for extracellular insults and intracellular homeostasis

FEBS Journal ◽  
2021 ◽  
Author(s):  
Rong Fu ◽  
Xiaowan Jiang ◽  
Gang li ◽  
Yi Zhu ◽  
Huimin Zhang
Keyword(s):  
Epithelial Cells ◽  
Junctional Complexes

A Freeze-Etching Study on Experimental Murine Mastitis

1978 ◽  
Vol 15 (5) ◽  
pp. 638-648 ◽  
Author(s):  
K. Smith ◽  
R. L. Chandler
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Potential Barrier ◽  
Mammary Glands ◽  
Pathological Changes ◽  
Intercellular Spaces ◽  
Freeze Etching ◽  
Junctional Complexes ◽  
Acinar Lumen

Streptococcal mastitis was produced experimentally in mice inoculated by the intramammary route; freeze-etched preparations from the affected mammary glands were studied by electron microscopy. The inoculated cocci were seen free in the acinar lumen, within luminal phagocytes and within cells of the epithelium. No significant pathological changes were noted in the junctional complexes between secretory epithelial cells. The results were comparable to those obtained by ultrathin sectioning and indicated that, while cocci can transfer from the acinar lumen into the substance of the epithelium and towards a subepithelial location, the junctional complexes between epithelial cells present a potential barrier to movement through the intercellular spaces.

scholarly journals Ultrastructure of intestinal mucosa in diarrhea-predominant irritable bowel syndrome

2019 ◽  
Vol 106 (3) ◽  
pp. 225-235 ◽  
Author(s):  
D-Y Zhao ◽  
Q-Q Qi ◽  
X Long ◽  
X Li ◽  
F-X Chen ◽  
...  
Keyword(s):  
Irritable Bowel Syndrome ◽  
Epithelial Cells ◽  
Healthy Volunteers ◽  
Confocal Laser Endomicroscopy ◽  
Bowel Habit ◽  
Confocal Laser ◽  
Pathophysiological Mechanism ◽  
Transmission Electron ◽  
Junctional Complexes ◽  
Irritable Bowel

Objectives Impaired intestinal barrier function has been demonstrated in the pathophysiology of diarrhea-predominant irritable bowel syndrome (IBS-D). This study aimed to describe the intestinal ultrastructural findings in the intestinal mucosal layer of IBS-D patients. Methods In total, 10 healthy controls and 10 IBS-D patients were analyzed in this study. The mucosa of each patient’s rectosigmoid colon was first assessed by confocal laser endomicroscopy (CLE); next, biopsied specimens of these sites were obtained. Intestinal tissues of IBS-D patients and healthy volunteers were examined to observe cellular changes by transmission electron microscopy (TEM). Results CLE showed no visible epithelial damage or inflammatory changes in the colonic mucosa of IBS-D compared with healthy volunteers. On transmission electron microscopic examination, patients with IBS-D displayed a larger apical intercellular distance with a higher proportion of dilated (>20 nm) intercellular junctional complexes, which was indicative of impaired mucosal integrity. In addition, microvillus exfoliation, extracellular vesicle as well as increased presence of multivesicular bodies were visible in IBS-D patients. Single epithelial cells appeared necrotic, as characterized by cytoplasmic vacuolization, cytoplasmic swelling, and presence of autolysosome. A significant association between bowel habit, frequency of abdominal pain, and enlarged intercellular distance was found. Conclusion This study showed ultrastructural alterations in the architecture of intestinal epithelial cells and intercellular junctional complexes in IBS-D patients, potentially representing a pathophysiological mechanism in IBS-D.

Desmosome-like structure between lymphocytes of developing thymus of foetal lamb

1990 ◽  
Vol 48 (3) ◽  
pp. 456-457
Author(s):  
Mohammed T. Alsalami
Keyword(s):  
Epithelial Cells ◽  
Full Term ◽  
Thymic Tissue ◽  
Stage Of Development ◽  
Junctional Complexes ◽  
Foetal Lamb

The foetal thymuses of sheep from 40 days to full term gestation were studied. The earliest thymuses that were studied were obtained from foetuses of 40 days gestation. At this stage of development the thymic tissue was formed of cords of condensed epithelial cells. Lymphopoiesis occurred in these thymuses between the thymus of 40 day old foetus and those of 42 days was striking and indicated that the onset of lymphopoiesis in the foetal sheep occurred abruptly. From 42 days onwards there was a rapid increase in the size of the thymus and in the extent of the lymphopoiesis (Fig. 1). By 45 days gestation the distribution of the lymph cells in the thymus had begun to define the cortex and medulla, and the organ was plainly lymphoid.Apart from lymphoid and epithelial cells, macrophages, erythroblasts and granulocytic myelocytes were sometimes found in the thymus (Fig. 2). Many of die lymphocytes within the cortex were closely attached to one another, the point of attachment resembling tight junctional complexes that normally found between epithelial cells (Fig. 3 and 4).

Junctional complexes of epithelial cells

Biochimie ◽  
1987 ◽  
Vol 69 (8) ◽  
pp. 905
Author(s):  
J. Cartaud
Keyword(s):  
Epithelial Cells ◽  
Junctional Complexes

scholarly journals Visualisation of Multiple Tight Junctional Complexes in Human Airway Epithelial Cells

2018 ◽  
Vol 20 (1) ◽  
Author(s):  
Alysia G. Buckley ◽  
Kevin Looi ◽  
Thomas Iosifidis ◽  
Kak-Ming Ling ◽  
Erika N. Sutanto ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Human Airway ◽  
Junctional Complexes ◽  
Human Airway Epithelial Cells

scholarly journals Localization of capping protein in chicken epithelial cells by immunofluorescence and biochemical fractionation.

1992 ◽  
Vol 118 (2) ◽  
pp. 335-346 ◽  
Author(s):  
D A Schafer ◽  
M S Mooseker ◽  
J A Cooper
Keyword(s):  
Epithelial Cells ◽  
Actin Filaments ◽  
Intestinal Epithelial Cells ◽  
Sensory Epithelium ◽  
Junctional Complex ◽  
Intestinal Epithelial ◽  
Capping Protein ◽  
Pigmented Epithelium ◽  
Biochemical Fractionation ◽  
Junctional Complexes

We have localized capping protein in epithelial cells of several chicken tissues using affinity-purified polyclonal antibodies and immunofluorescence. Capping protein has a distribution in each tissue coincident with proteins of the cell-cell junctional complex, which includes the zonula adherens, zonula occludens, and desmosome. "En face" views of the epithelial cells showed capping protein distributed in a polygonal pattern coincident with cell boundaries in intestinal epithelium, sensory epithelium of the cochlea, and the pigmented epithelium of the retina and at regions of cell-cell contact between chick embryo kidney cells in culture. "Edge-on" views obtained by confocal microscopy of intact single intestinal epithelial cells and of retinal pigmented epithelium showed that capping protein is located in the apical region of the epithelial cells coincident with the junctional complexes. These images do not resolve the individual types of junctions of the junctional complex. Immunolabeling of microvilli or stereocilia was faint or not detectable. Capping protein was also detected in the cytoplasm of intact intestinal epithelial cells and in nuclei of cells in the pigmented retina and in the kidney cell cultures, but not in nuclei of cells of the intestinal epithelium or sensory epithelium. Biochemical fractionation of isolated intestinal epithelial cells shows capping protein in the brush border fraction, which contains the junctional complexes, and in the soluble fraction. These results are consistent with the results of the immunolabeling experiments. Highly purified microvilli of the brush borders also contained capping protein; this result was unexpected based on the low intensity of immunofluorescence staining of microvilli and stereocilia. The microvilli were not contaminated with junctional complexes, as defined by the absence of several markers for cell junctions. The cause and significance of this discrepancy is not certain at this time. Since capping protein binds the barbed end of actin filaments in vitro, we hypothesize that capping protein is bound to the barbed ends of actin filaments associated with one or more of the junctions of the junctional complex.

Sign in / Sign up

Export Citation Format

Share Document