Profiling of microdissected gastric epithelial cells reveals a cell type—specific response to Helicobacter pylori infection

Helicobacter pylori infection is associated with important gastric pathologies. An aggressive proinflammatory immune response is generated in the gastric tissue infected with H. pylori, resulting in gastritis and a series of morphological changes that increase the susceptibility to cancer development. Probiotics could present an alternative solution to prevent or decrease H. pylori infection. Among them, the use of immunomodulatory lactic acid bacteria represents a promising option to reduce the severity of chronic inflammatory-mediated tissue damage and to improve protective immunity against H. pylori. We previously isolated Lactobacillus fermentum UCO-979C from human gastric tissue and demonstrated its capacity to reduce adhesion of H. pylori to human gastric epithelial cells (AGS cells). In this work, the ability of L. fermentum UCO-979C to modulate immune response in AGS cells and PMA phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 (human monocytic leukaemia) macrophages in response to H. pylori infection was evaluated. We demonstrated that the UCO-979C strain is able to differentially modulate the cytokine response of gastric epithelial cells and macrophages after H. pylori infection. Of note, L. fermentum UCO-979C was able to significantly reduce the production of inflammatory cytokines and chemokines in AGS and THP-1 cells as well as increase the levels of immunoregulatory cytokines, indicating a remarkable anti-inflammatory effect. These findings strongly support the probiotic potential of L. fermentum UCO-979C and provide evidence of its beneficial effects against the inflammatory damage induced by H. pylori infection. Although our findings should be proven in appropriate experiments in vivo, in both H. pylori infection animal models and human trials, the results of the present work provide a scientific rationale for the use of L. fermentum UCO-979C to prevent or reduce H. pylori-induced gastric inflammation in humans.

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Identification of a cell-type-specific transcriptional repressor in the promoter region of the mouse hepatocyte growth factor gene

Molecular and Cellular Biology ◽

10.1128/mcb.14.11.7046-7058.1994 ◽

1994 ◽

Vol 14 (11) ◽

pp. 7046-7058

Author(s):

Y Liu ◽

A B Beedle ◽

L Lin ◽

A W Bell ◽

R Zarnegar

Keyword(s):

Epithelial Cells ◽

Promoter Region ◽

Nuclear Protein ◽

Transcriptional Repressor ◽

Cell Type ◽

Mobility Shift ◽

A Cell ◽

Cell Type Specific ◽

Gel Mobility Shift ◽

Hepatocyte Growth

Hepatocyte growth factor (HGF), a cytokine with multiple functions, exhibits cell-type-specific as well as cytokine- and steroid hormone-regulated expression. The HGF gene is known to be expressed predominately in mesenchymal but not in epithelial cells. In this study, we report the identification of a cell-type-specific transcriptional repressor in the promoter region of the mouse HGF gene, which is evidently responsible for the suppression of HGF expression in epithelial cells. Gel mobility shift assays and DNase I footprinting studies revealed that a 27-bp element (-16 to +11) around the transcription initiation site is responsible for the binding of a nuclear protein which is present in epithelial but not in mesenchymally derived cells. Further analysis of the binding activity of the DNA region with nuclear protein revealed that an approximately 19-bp sequence containing a unique palindromic structure (5'-AACCGACCGGTT-3') overlapped by a CAP box is essential for binding. Substitution of a single base (the contact site) within this region by site-directed mutagenesis resulted in total abrogation of the binding of the nuclear protein and a concomitant increase in the transcriptional activity of various lengths of HGF-chloramphenicol acetyltransferase fused genes when transfected into the epithelial cell line RL95-2 but not the mesenchymal cell line NIH 3T3. Southwestern (DNA-protein) analyses revealed that the nuclear protein which binds to this repressor element is a single polypeptide of approximately 70 kDa. Analysis of the nuclear extract prepared from regenerating mouse liver at various times after two-thirds partial hepatectomy by gel mobility shift assay revealed a substantial reduction (more than 75% within 3 h) in the binding of the repressor to its cognate binding site. Our results suggest that a cis-acting transcriptional repressor in the promoter region of the mouse HGF gene is involved in cell-type-specific regulation through binding to its cognate trans-acting protein which exists in epithelial cells but is absent in fibroblast cells.

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Helicobacter pylori Infection Activates the Akt–Mdm2–p53 Signaling Pathway in Gastric Epithelial Cells

Digestive Diseases and Sciences ◽

10.1007/s10620-014-3470-2 ◽

2014 ◽

Vol 60 (4) ◽

pp. 876-886 ◽

Cited By ~ 11

Author(s):

Xu Shu ◽

Zhen Yang ◽

Zhong-Hua Li ◽

Lian Chen ◽

Xiao-Dong Zhou ◽

...

Keyword(s):

Helicobacter Pylori ◽

Epithelial Cells ◽

Signaling Pathway ◽

Helicobacter Pylori Infection ◽

Gastric Epithelial Cells ◽

P53 Signaling ◽

P53 Signaling Pathway

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Accumulation of abasic sites induces genomic instability in normal human gastric epithelial cells during Helicobacter pylori infection

Oncogenesis ◽

10.1038/oncsis.2014.42 ◽

2014 ◽

Vol 3 (11) ◽

pp. e128-e128 ◽

Cited By ~ 30

Author(s):

D Kidane ◽

D L Murphy ◽

J B Sweasy

Keyword(s):

Helicobacter Pylori ◽

Epithelial Cells ◽

Genomic Instability ◽

Helicobacter Pylori Infection ◽

Gastric Epithelial Cells ◽

Abasic Sites ◽

Normal Human

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Helicobacter pylori infection increases sirt2 gene expression in gastric epithelial cells of gastritis patients

Microbial Pathogenesis ◽

10.1016/j.micpath.2017.12.078 ◽

2018 ◽

Vol 116 ◽

pp. 120-123 ◽

Cited By ~ 6

Author(s):

Seiran Zandi ◽

Manouchehr A. Hedayati ◽

Ebrahim Mohammadi ◽

Farshad Sheikhesmaeili

Keyword(s):

Gene Expression ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Helicobacter Pylori Infection ◽

Gastric Epithelial Cells ◽

Sirt2 Gene

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Identification of a cell-type-specific transcriptional repressor in the promoter region of the mouse hepatocyte growth factor gene.

Molecular and Cellular Biology ◽

10.1128/mcb.14.11.7046 ◽

1994 ◽

Vol 14 (11) ◽

pp. 7046-7058 ◽

Cited By ~ 24

Author(s):

Y Liu ◽

A B Beedle ◽

L Lin ◽

A W Bell ◽

R Zarnegar

Keyword(s):

Epithelial Cells ◽

Promoter Region ◽

Nuclear Protein ◽

Transcriptional Repressor ◽

Cell Type ◽

Mobility Shift ◽

A Cell ◽

Cell Type Specific ◽

Gel Mobility Shift ◽

Hepatocyte Growth

Hepatocyte growth factor (HGF), a cytokine with multiple functions, exhibits cell-type-specific as well as cytokine- and steroid hormone-regulated expression. The HGF gene is known to be expressed predominately in mesenchymal but not in epithelial cells. In this study, we report the identification of a cell-type-specific transcriptional repressor in the promoter region of the mouse HGF gene, which is evidently responsible for the suppression of HGF expression in epithelial cells. Gel mobility shift assays and DNase I footprinting studies revealed that a 27-bp element (-16 to +11) around the transcription initiation site is responsible for the binding of a nuclear protein which is present in epithelial but not in mesenchymally derived cells. Further analysis of the binding activity of the DNA region with nuclear protein revealed that an approximately 19-bp sequence containing a unique palindromic structure (5'-AACCGACCGGTT-3') overlapped by a CAP box is essential for binding. Substitution of a single base (the contact site) within this region by site-directed mutagenesis resulted in total abrogation of the binding of the nuclear protein and a concomitant increase in the transcriptional activity of various lengths of HGF-chloramphenicol acetyltransferase fused genes when transfected into the epithelial cell line RL95-2 but not the mesenchymal cell line NIH 3T3. Southwestern (DNA-protein) analyses revealed that the nuclear protein which binds to this repressor element is a single polypeptide of approximately 70 kDa. Analysis of the nuclear extract prepared from regenerating mouse liver at various times after two-thirds partial hepatectomy by gel mobility shift assay revealed a substantial reduction (more than 75% within 3 h) in the binding of the repressor to its cognate binding site. Our results suggest that a cis-acting transcriptional repressor in the promoter region of the mouse HGF gene is involved in cell-type-specific regulation through binding to its cognate trans-acting protein which exists in epithelial cells but is absent in fibroblast cells.

Download Full-text