Evidence map›Paper›PMID 30909866›Full record

ArticleBMC microbiology2019

Development of flow cytometry based adherence assay for Neisseria gonorrhoeae using 5'-carboxyfluorosceinsuccidyl ester.

Sidharath Dev Thakur, Milan Obradovic, Jo-Anne R Dillon, Siew Hon Ng, Heather L Wilson

Open access · goldAbstract read
In one paragraph

Article in BMC microbiology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
0.5field-weighted citation impact, top 37% 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

5 citing papers in PubMed, 7 citations in OpenAlex.

  1. Internalization ofMicroorganisms · 2025
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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

5 authors at 1 institution in 1 country.

Sidharath Dev ThakurVaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
Milan ObradovicVaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
Jo-Anne R DillonVaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
Siew Hon NgVaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
Heather L WilsonVaccine and Infectious Disease Organization - International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada. heather.wilson@usask.ca.ORCID 0000-0002-1261-0901
University of Saskatchewan · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundNeisseria gonorrhoeae is an obligate human pathogen and its adherence to host cells is essential for its pathogenesis. Gonococcal adherence assays are based on the enumeration of bacteria attached to human cells on solid media. Because conventional adherence assays are based on bacterial counts, they are often time consuming to perform and prone to observer bias. A flow cytometry based method, using the cell-permeable fluorescent dye 5'-carboxyfluoroscein succidyl ester (CFSE), was developed to dramatically increase the number of adherent N. gonorrhoeae quantified per assay while improving repeatability and removing observer bias. Piliated N. gonorrhoeae F62 were stained with CFSE then the staining reaction was quenched with foetal bovine serum. Human cervical ME-180 cells were infected with CFSE-stained N. gonorrhoeae (multiplicity of the infection 100:1) for 2 h. Infected cells were washed to remove loosely adhered bacteria. Flow cytometry was used to quantify the percentage of ME-180 cells associated with CFSE-stained N. gonorrhoeae and a minimum of 30,000 events were recorded. Real time-PCR analysis targeting opa gene (encoding N. gonorrhoeae opacity associated gonococcal outer membrane protein) was performed on infected ME-180 cells to confirm the flow cytometric adherence assay results. A rabbit was immunized with heat-killed N. gonorrhoeaeF62 to generate hyperimmune serum. The functional compatibility of the assay was confirmed by studying the effect of N. gonorrhoeae F62 antiserum on blocking adherence/invasion of CFSE-stained bacteria to ME-180 cells.

resultsWe observed that 20.3% (+/- 1.0) ME-180 cells were associated with CFSE-stained N. gonorrhoeae. Heat-inactivated hyperimmune serum, at 1:10 to 1:80 dilutions, significantly inhibited gonococcal adherence by 6 and 3 fold, respectively. Real time-PCR analysis targeting opa gene confirmed that hyperimmune serum blocked adherence/invasion of N. gonorrhoeae to the ME-180 cells in a dilution-dependent manner.

conclusionsFlow cytometric analysis was amenable to quick, easy and high-throughput quantification of the association of N. gonorrhoeae with ME-180 cells and was functionally confirmed using PCR analysis. These approaches may be adapted for in vitro and in vivo adherence studies related to gonococcal pathogenesis.

Indexed as

Bacterial AdhesionBacterial Outer Membrane ProteinsCell LineCervix UteriEpithelial CellsFemaleFlow CytometryFluoresceinsFluorescent DyesHumansNeisseria gonorrhoeaeSuccinimides5-(6)-carboxyfluorescein diacetate succinimidyl esterBacterial Outer Membrane ProteinsFluoresceinsFluorescent DyesOpa protein, NeisseriaSuccinimides5′-carboxyfluoroscein succidyl esterFlow cytometryNeisseria gonorrhoeaeNeutralizing antibodies

Identifiers

PMID30909866
PMCPMC6434840
OpenAlexW2941821118

What OpenQuestion holds

Textmetadata
LicenceCC BY
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.