Campylobacter fetusadheres to and enters INT 407 cells

2002 ◽  
Vol 48 (11) ◽  
pp. 995-1007 ◽  
Author(s):  
Lori L Graham
Keyword(s):  
Epithelial Cell ◽  
Cell Line ◽  
Reference Strain ◽  
Immunofluorescence Microscopy ◽  
Host Cells ◽  
Clinical Isolates ◽  
Epithelial Cell Line ◽  
Infection Period ◽  
Campylobacter Fetus

Campylobacter fetus is a Gram-negative bacterial pathogen of humans and ungulates and is normally transmitted via ingestion of contaminated food or water with infection resulting in mild to severe enteritis. However, despite clinical evidence that C. fetus infection often involves transient bacteremic states from which systemic infection may develop and the frequent isolation of C. fetus from extra-intestinal sites, this organism displays very poor invasiveness in in vitro models of infection. In this study, immunofluorescence microscopy and gentamicin protection assays were used to investigate the ability of six clinical isolates and one reference strain of C. fetus to adhere to and invade the human intestinal epithelial cell line, INT 407. During an initial 4-h infection period, all C. fetus strains were detected intracellularly using both techniques, though adherence and internalization levels were very low when determined from gentamicin protection assays. Microscopy results indicated that during a 4-h infection period, four of the five clinical strains tested were adherent to 41.3–87.3% of INT 407 cells observed and that 25.2–34.6% of INT 407 cells contained intracellular C. fetus. The C. fetus reference strain displayed the lowest levels of adherence and internalization. A modified infection assay revealed thatC. fetus adherence did not necessarily culminate in internalization. Despite the large percentage of INT 407 cells with adherent bacteria, the percentage of INT 407 cells with intracellular bacteria remained unchanged when incubation was extended from 4 h to 20 h. However, microscopy of INT 407 cells 24 h postinfection (p.i.) revealed that infected host cells contained clusters of densely packed C. fetus cells. Gentamicin protection assays revealed that intracellular C. fetus cells were not only viable 24 h p.i. but also that C. fetus had increased in number approximately three- to fourfold between 4 and 24 h p.i., indicative of intracellular replication. Investigation of the role of the host cell cytoskeleton revealed that pretreatment of host cells with cytochalasin D, colchicine, vinblastine, taxol, or dimethyl sulfoxide (DMSO) did not impact upon C. fetus adherence or internalization of INT 407 cells. Microscopy indicated neither rearrangement nor colocalization of either microtubules or microfilaments in INT 407 cells in response to C. fetus adherence or internalization. Together, these data indicate that clinical isolates of C. fetus are capable of adhering, entering, and surviving within the nonphagocytic epithelial cell line, INT 407.Key words: Campylobacter fetus, INT 407, immunofluorescence microscopy, S layer.

scholarly journals Biofilm Formation Capability of Clinical Helicobacter pylori Isolates on MKN-45 Cells

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Bahareh Attaran ◽  
Tahereh Falsafi ◽  
Mahboubeh Kabiri
Keyword(s):  
Epithelial Cell ◽  
Cell Line ◽  
Biofilm Formation ◽  
Clinical Isolates ◽  
Epithelial Cell Line ◽  
Electron Microscopic ◽  
H Pylori ◽  
Adhesion Index

Background: In vitro biofilm formation of H. pylori is demonstrated; however, its potential role in the persistent infection of the human stomach has not yet been addressed. Objectives: The aim of this study was to assess the biofilm formation of clinical H. pylori isolates on an epithelial cell line, a line that produces mucin. Methods: H. pylori isolates consisting of an efficient (19B) and a weak (4B) biofilm formation ability, were selected from screening of the clinical isolates. Their adhesion index was determined after 2h incubation with the semi-confluent monolayers of MKN-45 cells. Their biofilm formation was evaluated after 24 and 72 h incubation with MKN-45 cells using a modified adherence assay developed in this work. Production of biofilm was quantitatively assessed by CFU enumeration and qualitatively by the immunofluorescence, and scanning-electron-microscopic (SEM) methods. Due to the importance of mucin in the binding of H. pylori and biofilm formation, the binding strength of the mucin binding protein, MUC5AC, and MUC1 with docking was investigated using cluspro webserver. Results: Using MKN-45 epithelial cell line as a model, significant differences were observed between the adhesion index of 19B and 4B isolates. After 24h, both isolates were able to form biofilms with significantly higher numbers of CFU for the 19B isolate. These results were confirmed by immunofluorescence and SEM such that after 24h, a cluster of coccoid bacteria on the MKN-45 cells in the form of microcolonies was observed. The docking results showed that MUC5AC demonstrated the most favorable interaction with H. pylori urease and BabA with docking energy scores of -931.1 and -906.3 kcal.mol-1, respectively. Conclusions: By developing an appropriate in situ biofilm assay, we investigated biofilm formation by clinical H. pylori isolates on the MKN-45 epithelial cell line. The establishment of such an in-situ model for studying the biofilm formation ability of clinical isolates can also be used to study cell-bacteria interactions in the context of a complex biofilm and also as a model for drug screening applications.

scholarly journals Normal keratinization in a spontaneously immortalized aneuploid human keratinocyte cell line.

1988 ◽  
Vol 106 (3) ◽  
pp. 761-771 ◽  
Author(s):  
P Boukamp ◽  
R T Petrussevska ◽  
D Breitkreutz ◽  
J Hornung ◽  
A Markham ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Cell Line ◽  
Human Skin ◽  
Cell Lines ◽  
Hacat Cell ◽  
Epithelial Cell Line ◽  
Spontaneous Transformation ◽  
Chromosomal Alterations ◽  
Hacat Cell Line

In contrast to mouse epidermal cells, human skin keratinocytes are rather resistant to transformation in vitro. Immortalization has been achieved by SV40 but has resulted in cell lines with altered differentiation. We have established a spontaneously transformed human epithelial cell line from adult skin, which maintains full epidermal differentiation capacity. This HaCaT cell line is obviously immortal (greater than 140 passages), has a transformed phenotype in vitro (clonogenic on plastic and in agar) but remains nontumorigenic. Despite the altered and unlimited growth potential, HaCaT cells, similar to normal keratinocytes, reform an orderly structured and differentiated epidermal tissue when transplanted onto nude mice. Differentiation-specific keratins (Nos. 1 and 10) and other markers (involucrin and filaggrin) are expressed and regularly located. Thus, HaCaT is the first permanent epithelial cell line from adult human skin that exhibits normal differentiation and provides a promising tool for studying regulation of keratinization in human cells. On karyotyping this line is aneuploid (initially hypodiploid) with unique stable marker chromosomes indicating monoclonal origin. The identity of the HaCaT line with the tissue of origin was proven by DNA fingerprinting using hypervariable minisatellite probes. This is the first demonstration that the DNA fingerprint pattern is unaffected by long-term cultivation, transformation, and multiple chromosomal alterations, thereby offering a unique possibility for unequivocal identification of human cell lines. The characteristics of the HaCaT cell line clearly document that spontaneous transformation of human adult keratinocytes can occur in vitro and is associated with sequential chromosomal alterations, though not obligatorily linked to major defects in differentiation.

scholarly journals In-vitro cytotoxicity of Trigona itama honey against human lung adenocarcinoma epithelial cell line (A549)

2019 ◽  
Vol 30 ◽  
pp. 100955 ◽  
Author(s):  
Siti Norfitrah Mohd Salim ◽  
Logaraj Ramakreshnan ◽  
Chng Saun Fong ◽  
Ridhwan Abdul Wahab ◽  
Mohammad Syaiful Bahari Abdull Rasad
Keyword(s):  
Epithelial Cell ◽  
Lung Adenocarcinoma ◽  
Cell Line ◽  
Human Lung ◽  
In Vitro Cytotoxicity ◽  
Epithelial Cell Line ◽  
Human Lung Adenocarcinoma

scholarly journals Listeria monocytogenes Infection of Bat Pipistrellus nathusii Epithelial cells Depends on the Invasion Factors InlA and InlB

Pathogens ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 867
Author(s):  
Olga Povolyaeva ◽  
Yaroslava Chalenko ◽  
Egor Kalinin ◽  
Olga Kolbasova ◽  
Elena Pivova ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Line ◽  
Domestic Animals ◽  
Epithelial Cell Line ◽  
Intracellular Pathogen ◽  
Wild Type ◽  
Listeria Monocytogenes Infection ◽  
Natural Hosts

L. monocytogenes is a widespread facultative intracellular pathogen. The range of natural hosts that supporting L. monocytogenes persistence in the environment has not been fully established yet. In this study, we were interested in the potential of L. monocytogenes to infect cells of bats, which are being increasingly recognized as a reservoir for microorganisms that are pathogenic to humans and domestic animals. A stable epithelial cell line was developed from the kidneys of Pipistrellus nathusii, a small bat widely distributed across Europe. The wild-type L. monocytogenes strain EGDe infected this cell line with an invasion efficiency of 0.0078 ± 0.0009%. Once it entered bat cells, L. monocytogenes doubled within about 70 min. When L. monocytogenes lacked either of the major invasion factors, InlA and InlB, invasion efficiency decreased by a factor of 10 and 25 respectively (p < 0.000001). The obtained results suggest that bat epithelial cells are susceptible to L. monocytogenes infection and that L. monocytogenes invasion of bat cells depends on the major invasion factors InlA and InlB. These results constitute the first report on in vitro studies of L. monocytogenes infection in bats.

Concentration- and time-dependent effects of enoxaparin on human adenocarcinomic epithelial cell line A549 proliferation in vitro

2011 ◽  
Vol 89 (10) ◽  
pp. 705-711 ◽  
Author(s):  
Walid Abu Arab ◽  
Rami Kotb ◽  
Marco Sirois ◽  
Éric Rousseau
Keyword(s):  
Epithelial Cell ◽  
Cell Line ◽  
Positive Impact ◽  
A549 Cells ◽  
Cell Counting ◽  
Epithelial Cell Line ◽  
Major Health Problem ◽  
Antineoplastic Effect ◽  
Cell Counts

Non-small cell lung cancer (NSCLC) is a major health problem. Surgery is the only potential curative treatment, in spite of the high recurrence and mortality rates. Low molecular weight heparins (LMWH) have been suggested to have a positive impact on the outcome of various cancers, mainly attributed to their anticoagulant properties; yet a direct antineoplastic effect has not been excluded. We thought to evaluate the direct effect of the LMWH enoxaparin on the human lung adenocarcinomic epithelial cell line A549 and to determine potential antiproliferative and antimetastatic effects that could guide future trials. A549 cells were cultured with different concentrations of enoxaparin (1–30 U/mL). Cell counting was performed at 24, 48, and 72 h. Detection of c-Myc protein and CD44 protein was performed by electrophoresis and Western blotting. Statistical analysis was performed using paired Student’s t tests. Cell counts were decreased with increasing concentrations and time of exposure to enoxaparin. This corresponds to decreased expression of c-Myc and CD44. In conclusion, enoxaparin displayed a direct dose and exposure duration dependent suppressor effect on A549 cell proliferation and the expression of both c-Myc and CD44 in vitro, suggesting reduced proliferative and metastatic potentials of these cells.

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