scholarly journals Intermediate filament cytoskeleton of amnion epithelium and cultured amnion epithelial cells: expression of epidermal cytokeratins in cells of a simple epithelium.

1985 ◽  
Vol 100 (4) ◽  
pp. 997-1009 ◽  
Author(s):  
S Regauer ◽  
W W Franke ◽  
I Virtanen

Using immunofluorescence microscopy and two-dimensional gel electrophoresis, we compared the cytoskeletal proteins expressed by human amnion epithelium in situ, obtained from pregnancies of from 10-wk to birth, with the corresponding proteins from cultured amnion epithelial cells and cultures of cells from the amniotic fluid of 16 week pregnancies. Epithelia of week 16 fetuses already display tissue-specific patterns of cytokeratin polypeptides which are similar, although not identical, to those of the corresponding adult tissues. In the case of the simple amnion epithelium, a complex and characteristic complement of cytokeratin polypeptides of Mr 58,000 (No. 5), 56,000 (No. 6), 54,000 (No. 7), 52,500 (No. 8), 50,000 (No. 14), 46,000 (No. 17), 45,000 (No. 18), and 40,000 (No. 19) is present by week 10 of pregnancy and is essentially maintained until birth, with the addition of cytokeratin No. 4 (Mr 59,000) and the disappearance of No. 7 (Mr 54,000) at week 16 of pregnancy. In full-term placentae, the amnion epithelium displays two morphologically distinct regions, i.e., a simple and a stratified epithelium, both of which express the typical amnion cytokeratin polypeptides. However, in addition the stratified epithelium also synthesizes large amounts of special epidermal cytokeratins such as No. 1 (Mr 68,000), 10 (Mr 56,500), and 11 (Mr 56,000). In culture amnion epithelial cells obtained from either 16-wk pregnancies or full-term placentae will continue to synthesize the amnion-typical cytokeratin pattern, except for a loss of detection of component No. 4. This pattern is considerably different from the cytokeratins synthesized by cultures of cells from amniotic fluids (cytokeratins No. 7, 8, 18, and 19, sometimes with trace amounts of No. 17) and from several so-called "amnion epithelial cell lines." In addition, amnion epithelial cells in situ as well as amnion epithelial cell cultures appear to be heterogeneous in that they possess some cells that co-express cytokeratins and vimentin. These observations lead to several important conclusions: In contrast to the general concept of recent literature, positively charged cytokeratins of the group No. 4-6 can be synthesized in a simple, i.e., one-layered epithelium. The change from simple to stratified amnion epithelium does not require a cessation of synthesis of cytokeratins of the simple epithelium type, but in this case keratins characteristic of the terminally differentiated epidermis (No. 1, 10, and 11) are also synthesized.(ABSTRACT TRUNCATED AT 400 WORDS)

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1696 ◽  
Author(s):  
Raghuraman C. Srinivasan ◽  
Stephen C. Strom ◽  
Roberto Gramignoli

Perinatal stem cells and epithelial cells isolated from full term amnion membrane, in particular, have attracted interest over the last decade, as a promising source of multipotent cells for cellular therapies. Human amnion epithelial cells (hAEC) have been used to treat monogenetic liver disease such as maple syrup urine disease or fibrosis of the liver in preclinical studies. In most studies xeno-transplants of hAEC were conducted without providing immunosuppression to recipients, reflecting the tolerogenic properties of hAEC. For many cell types, successful cryopreservation is critical for providing a readily available, off-the-shelf product. In this study, hAEC were isolated from full-term human placenta from 14 different donors, cryopreserved using a protocol and reagents commonly adopted for epithelial cell preservation. The cells were analyzed in terms of survival, recovery, and homogeneity, profiled for surface markers characteristic of epithelial, mesenchymal, endothelial, or hematopoietic cells. There were no significant differences observed in the percentage of cells with epithelial cell markers before and after cryopreservation. The relative proportion of stromal and hematopoietic cells was significantly reduced in hAEC preparations after cryopreservation. The expression of stem cell and immunomodulatory molecules were confirmed in the final product. Since multipotent cells are readily available from full-term placenta, this novel cell source might significantly increase the number of patients eligible to receive cellular therapies for liver and other diseases.


2003 ◽  
Vol 285 (5) ◽  
pp. C1304-C1313 ◽  
Author(s):  
O. K. Nihei ◽  
A. C. Campos de Carvalho ◽  
D. C. Spray ◽  
W. Savino ◽  
L. A. Alves

We here describe intercellular calcium waves as a novel form of cellular communication among thymic epithelial cells. We first characterized the mechanical induction of intercellular calcium waves in different thymic epithelial cell preparations: cortical 1-4C18 and medullary 3-10 thymic epithelial cell lines and primary cultures of thymic “nurse” cells. All thymic epithelial preparations responded with intercellular calcium wave propagation after mechanical stimulation. In general, the propagation efficacy of intercellular calcium waves in these cells was high, reaching 80-100% of the cells within a given confocal microscopic field, with a mean velocity of 6-10 μm/s and mean amplitude of 1.4- to 1.7-fold the basal calcium level. As evaluated by heptanol and suramin treatment, our results suggest the participation of both gap junctions and P2 receptors in the propagation of intercellular calcium waves in thymic nurse cells and the more prominent participation of gap junctions in thymic epithelial cell lines. Finally, in cocultures, the transmission of intercellular calcium wave was not observed between the mechanically stimulated thymic epithelial cell and adherent thymocytes, suggesting that intercellular calcium wave propagation is limited to thymic epithelial cells and does not affect the neighboring thymocytes. In conclusion, these data describe for the first time intercellular calcium waves in thymic epithelial cells and the participation of both gap junctions and P2 receptors in their propagation.


Cells ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 2240
Author(s):  
Marwa Zafarullah ◽  
Mittal Jasoliya ◽  
Flora Tassone

Fragile X syndrome (FXS) is an X-linked neurodevelopmental condition associated with intellectual disability and behavioral problems due to the lack of the Fragile X mental retardation protein (FMRP), which plays a crucial role in synaptic plasticity and memory. A desirable in vitro cell model to study FXS would be one that can be generated by simple isolation and culture method from a collection of a non-invasive donor specimen. Currently, the various donor-specific cells can be isolated mainly from peripheral blood and skin biopsy. However, they are somewhat invasive methods for establishing cell lines from the primary subject material. In this study, we characterized a cost-effective and straightforward method to derive epithelial cell lines from urine samples collected from participants with FXS and healthy controls (TD). The urine-derived cells expressed epithelial cell surface markers via fluorescence-activated cell sorting (FACS). We observed inter, and the intra-tissue CGG mosaicism in the PBMCs and the urine-derived cells from participants with FXS potentially related to the observed variations in the phenotypic and clinical presentation FXS. We characterized these urine-derived epithelial cells for FMR1 mRNA and FMRP expression and observed some expression in the lines derived from full mutation mosaic participants. Further, FMRP expression was localized in the cytoplasm of the urine-derived epithelial cells of healthy controls. Deficient FMRP expression was also observed in mosaic males, while, as expected, no expression was observed in cells derived from participants with a hypermethylated full mutation.


2018 ◽  
Vol 92 (15) ◽  
Author(s):  
Philippa Hillyer ◽  
Rachel Shepard ◽  
Megan Uehling ◽  
Mina Krenz ◽  
Faruk Sheikh ◽  
...  

ABSTRACT Respiratory syncytial virus (RSV) infects small foci of respiratory epithelial cells via infected droplets. Infection induces expression of type I and III interferons (IFNs) and proinflammatory cytokines, the balance of which may restrict viral replication and affect disease severity. We explored this balance by infecting two respiratory epithelial cell lines with low doses of recombinant RSV expressing green fluorescent protein (rgRSV). A549 cells were highly permissive, whereas BEAS-2B cells restricted infection to individual cells or small foci. After infection, A549 cells expressed higher levels of IFN-β-, IFN-λ-, and NF-κB-inducible proinflammatory cytokines. In contrast, BEAS-2B cells expressed higher levels of antiviral interferon-stimulated genes, pattern recognition receptors, and other signaling intermediaries constitutively and after infection. Transcriptome analysis revealed that constitutive expression of antiviral and proinflammatory genes predicted responses by each cell line. These two cell lines provide a model for elucidating critical mediators of local control of viral infection in respiratory epithelial cells. IMPORTANCE Airway epithelium is both the primary target of and the first defense against respiratory syncytial virus (RSV). Whether RSV replicates and spreads to adjacent epithelial cells depends on the quality of their innate immune responses. A549 and BEAS-2B are alveolar and bronchial epithelial cell lines, respectively, that are often used to study RSV infection. We show that A549 cells are permissive to RSV infection and express genes characteristic of a proinflammatory response. In contrast, BEAS-2B cells restrict infection and express genes characteristic of an antiviral response associated with expression of type I and III interferons. Transcriptome analysis of constitutive gene expression revealed patterns that may predict the response of each cell line to infection. This study suggests that restrictive and permissive cell lines may provide a model for identifying critical mediators of local control of infection and stresses the importance of the constitutive antiviral state for the response to viral challenge.


2002 ◽  
Vol 70 (5) ◽  
pp. 2670-2675 ◽  
Author(s):  
T. E. Secott ◽  
T. L. Lin ◽  
C. C. Wu

ABSTRACT Attachment and ingestion of Mycobacterium avium subsp. paratuberculosis by two epithelial cell lines were enhanced by soluble fibronectin (FN). Peptide blocking of the FN attachment protein (FAP-P) inhibited the internalization of M. avium subsp. paratuberculosis. Disruption of FAP-P expression significantly reduced attachment and ingestion of M. avium subsp. paratuberculosis by T-24 and Caco-2 cells. The results indicate that the interaction between FN and FAP-P facilitates attachment and internalization of M. avium subsp. paratuberculosis by epithelial cells.


1998 ◽  
Vol 46 (5) ◽  
pp. 661-668 ◽  
Author(s):  
Alfredo Martínez ◽  
Andrew Farr ◽  
Michele D. Vos ◽  
Frank Cuttitta ◽  
Anthony M. Treston

C-terminal amidation is a post-translational processing step necessary to convey biological activity to a large number of regulatory peptides. In this study we have demonstrated that the peptidyl-glycine α-amidating monooxygenase enzyme complex (PAM) responsible for this activity is located in the medullary stellate epithelial cells of the thymus and in cultured epithelial cells bearing a medullary phenotype, using Northern blot, immunocytochemistry, in situ hybridization, and enzyme assays. Immunocytochemical localization revealed a granular pattern in the cytoplasm of the stellate cells, which were also positive for cytokeratins and a B-lymphocyte-associated antigen. The presence of PAM activity in medium conditioned by thymic epithelial cell lines suggests that PAM is a secreted product of these cells. Among the four epithelial cell lines examined, there was a direct correlation between PAM activity and content of oxytocin, an amidated peptide. Taken together, these data provide convincing evidence that thymic epithelial cells have the capacity to generate amidated peptides that may influence T-cell differentiation and suggest that the amidating enzymes could play an important role in the regulation of thymic physiology.


1988 ◽  
Vol 34 (6) ◽  
pp. 757-766 ◽  
Author(s):  
Jan M. De Boer ◽  
Friso H. F. Plantema

From patients with bacterial vaginosis motile, anaerobic, comma-shaped bacteria can be isolated, which have recently been placed into the new genus Mobiluncus. In this study, electron microscopy was used to examine the in situ adherence of these motile curved rods to detached epithelial cells (comma cells) in vaginal fluid from two patients with bacterial vaginosis. Thin sections showed that the curved rods attached both directly to the epithelial cell surface and at various distances from it. It is concluded that after initial attachment these motile bacteria can grow at the epithelial cell surface in sessile microcolonies. Ruthenium red staining demonstrated a coating of precipitated glycocalyx material both on the surface of the curved rods and on their flagella. This may indicate that in situ the adherent curved rods were enclosed in a very hydrated matrix of exopolysaccharides. Conspicuous was the ability of the curved rods to attach to the epithelial cell surface via their cell tips. However, in situ no specialized bacterial cell surface structures were seen that might explain this polar attachment. Electron microscopy of pure cultures demonstrated that both Mobiluncus curtisii subsp. curtisii and Mobiluncus mulieris can produce a glycocalyx in vitro.


2001 ◽  
Vol 75 (23) ◽  
pp. 11834-11850 ◽  
Author(s):  
Max Ciarlet ◽  
Sue E. Crawford ◽  
Mary K. Estes

ABSTRACT Infection of epithelial cells by some animal rotaviruses, but not human or most animal rotaviruses, requires the presence ofN-acetylneuraminic (sialic) acid (SA) on the cell surface for efficient infectivity. To further understand how rotaviruses enter susceptible cells, six different polarized epithelial cell lines, grown on permeable filter membrane supports containing 0.4-μm pores, were infected apically or basolaterally with SA-independent or SA-dependent rotaviruses. SA-independent rotaviruses applied apically or basolaterally were capable of efficiently infecting both sides of the epithelium of all six polarized cell lines tested, while SA-dependent rotaviruses only infected efficiently through the apical surface of five of the polarized cell lines tested. Regardless of the route of virus entry, SA-dependent and SA-independent rotaviruses were released almost exclusively from the apical domain of the plasma membrane of polarized cells before monolayer disruption or cell lysis. The transepithelial electrical resistance (TER) of cells decreased at the same time, irrespective of whether infection with SA-independent rotaviruses occurred apically or basolaterally. The TER of cells infected apically with SA-dependent rotaviruses decreased earlier than that of cells infected basolaterally. Rotavirus infection decreased TER before the appearance of cytopathic effect and cell death and resulted in an increase in the paracellular permeability to [3H]inulin as a function of loss of TER. The presence of SA residues on either the apical or basolateral side was determined using a Texas Red-conjugated lectin, wheat germ agglutinin (WGA), which binds SA residues. WGA bound exclusively to SA residues on the apical surface of the cells, confirming the requirement for SA residues on the apical cell membrane for efficient infectivity of SA-dependent rotaviruses. These results indicate that the rotavirus SA-independent cellular receptor is present on both sides of the epithelium, but SA-dependent and SA-independent rotavirus strains infect polarized epithelial cells by different mechanisms, which may be relevant for pathogenesis and selection of vaccine strains. Finally, rotavirus-induced alterations of the epithelial barrier and paracellular permeability suggest that common mechanisms of pathogenesis may exist between viral and bacterial pathogens of the intestinal tract.


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