Abstract
Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer), are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS) we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasomeenriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance.
| Original language | English |
|---|---|
| Article number | e9716 |
| Journal | PLoS One |
| Volume | 5 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2010 |
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ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Biochemistry, Genetics and Molecular Biology(all)
- Medicine(all)
Cite this
In vivo accumulation of Helicobacter pylori products, NOD1, ubiquitinated proteins and proteasome in a novel cytoplasmic structure. / Necchi, Vittorio; Sommi, Patrizia; Ricci, Vittorio; Solcia, Enrico.
In: PLoS One, Vol. 5, No. 3, e9716, 2010.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - In vivo accumulation of Helicobacter pylori products, NOD1, ubiquitinated proteins and proteasome in a novel cytoplasmic structure
AU - Necchi, Vittorio
AU - Sommi, Patrizia
AU - Ricci, Vittorio
AU - Solcia, Enrico
PY - 2010
Y1 - 2010
N2 - Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer), are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS) we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasomeenriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance.
AB - Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer), are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS) we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasomeenriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance.
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UR - http://www.scopus.com/inward/citedby.url?scp=78249235456&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0009716
DO - 10.1371/journal.pone.0009716
M3 - Article
C2 - 20300534
AN - SCOPUS:78249235456
VL - 5
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 3
M1 - e9716
ER -