Evidence map›Paper›PMID 16543403›Full record

ArticleJournal of leukocyte biology2006

Role of urease in megasome formation and Helicobacter pylori survival in macrophages.

Justin T Schwartz, Lee-Ann H Allen

Open access · greenAbstract read
In one paragraph

Article in Journal of leukocyte biology, 2006. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 55 papers.

0numbers the graph read from it
0cells of the map it votes in
55citing papers in PubMed
5.8field-weighted citation impact, top 4% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

55 citing papers in PubMed, 112 citations in OpenAlex.

  1. Article
  2. Review
  3. Article
  4. TargetingNutrients · 2025
    Review
  5. Review
  6. Dysregulated macrophage immunity inFrontiers in immunology · 2025
    Review
  7. Can Pyomelanin Produced byInternational journal of molecular sciences · 2023
    Article
  8. Article
  9. ReplicativebioRxiv : the preprint server for biology · 2023
    Article
  10. Review
  11. Antigenic Determinant ofPathogens (Basel, Switzerland) · 2022
    Article
  12. Article
  13. FromWorld journal of clinical oncology · 2022
    Review
  14. Frontiers in immunology · 2022
    Article
  15. Article
  16. Review
  17. Clinical Strains ofFrontiers in pharmacology · 2021
    Article
  18. Journal of clinical medicine · 2020
    Review
  19. Determinants of Phagosomal pH During Host-Pathogen Interactions.Frontiers in cell and developmental biology · 2020
    Review
  20. Are Histopathological Changes ofOpen access Macedonian journal of medical sciences · 2019
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors at 2 institutions in 1 country.

Justin T SchwartzDepartment of Medicine, University of Iowa and the VA Medical Center, Iowa City, IA, USA.
Lee-Ann H Allen
Iowa City VA Medical Center · USUniversity of Iowa · US

Funding

INTERACTION OF HELICOBACTER PYLORI WITH PHAGOCYTESR01AI043617 · NIAID · UNIVERSITY OF IOWA · PI ALLEN, LEE-ANN H. · 2000 to 2003
$860k
NIAID NIH HHS R01 AI043617NIAID NIH HHS R01 AI43617
6 · The paper itself

Abstract

Previous studies have demonstrated that Helicobacter pylori (Hp) delays its entry into macrophages and persists inside megasomes, which are poorly acidified and accumulate early endosome autoantigen 1. Herein, we explored the role of Hp urease in bacterial survival in murine peritoneal macrophages and J774 cells. Plasmid-free mutagenesis was used to replace ureA and ureB with chloramphenicol acetyltransferase in Hp Strains 11637 and 11916. ureAB null Hp lacked detectable urease activity and did not express UreA or UreB as judged by immunoblotting. Deletion of ureAB had no effect on Hp binding to macrophages or the rate or extent of phagocytosis. However, intracellular survival of mutant organisms was impaired significantly. Immunofluorescence microscopy demonstrated that (in contrast to parental organisms) mutant Hp resided in single phagosomes, which were acidic and accumulated the lysosome marker lysosome-associated membrane protein-1 but not early endosome autoantigen 1. A similar phenotype was observed for spontaneous urease mutants derived from Hp Strain 60190. Treatment of macrophages with bafilomycin A1, NH4Cl, or chloroquine prevented acidification of phagosomes containing mutant Hp. However, only ammonium chloride enhanced bacterial viability significantly. Rescue of ureAB null organisms was also achieved by surface adsorption of active urease. Altogether, our data indicate a role for urease and urease-derived ammonia in megasome formation and Hp survival.

Indexed as

AdsorptionAmmoniaAmmonium ChlorideAnimalsAutoantigensCell LineChloroquineEnzyme InductionFemaleGene DeletionGenes, ReporterHelicobacter pyloriHydrogen-Ion ConcentrationLysosomal-Associated Membrane Protein 1Lysosomal Membrane ProteinsMacrolidesAmmoniaAmmonium ChlorideAutoantigensbafilomycin A1Chloroquineearly endosome antigen 1Lamp1 protein, mouseLysosomal-Associated Membrane Protein 1Lysosomal Membrane ProteinsMacrolidesMembrane ProteinsNitric Oxide Synthase Type IINos2 protein, mouseUreaseVesicular Transport Proteins

Identifiers

PMID16543403
PMCPMC1868427
OpenAlexW2139763904

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.