Evidence map›Paper›PMID 42634491›Full record

ArticleMicrobial biotechnology2026

Pre-Clinical Development of Two DNA Vaccines Encoding MrkA of Klebsiella pneumoniae: Effect of Plasmid Backbone on Immunogenicity and Protective Efficacy Against Sepsis.

Marta Vicente-Pazos, Estéfani García-Ríos, Laura Quílez-Agraz, Gal la Ustrell-Sallent, Pilar Pérez-Romero, Mireia López-Siles, Michael J McConnell

Abstract read
In one paragraph

Article in Microbial biotechnology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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

7 authors.

Marta Vicente-PazosIntrahospital Infections Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain.ORCID https://orcid.org/0000-0003-2311-314X
Estéfani García-RíosInstituto de Ciencias de la Vida y del Vino (CSIC, Universidad de La Rioja, Gobierno de La Rioja), Logroño, Spain.ORCID https://orcid.org/0000-0001-9028-055X
Laura Quílez-AgrazMicrobiology of Intestinal Diseases, Department of Biology, Universitat de Girona, Girona, Spain.ORCID https://orcid.org/0009-0003-7464-5338
Gal la Ustrell-SallentMicrobiology of Intestinal Diseases, Department of Biology, Universitat de Girona, Girona, Spain.ORCID https://orcid.org/0009-0005-8992-1985
Pilar Pérez-RomeroDepartment of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.ORCID https://orcid.org/0000-0003-3026-7905
Mireia López-SilesMicrobiology of Intestinal Diseases, Department of Biology, Universitat de Girona, Girona, Spain.ORCID https://orcid.org/0000-0002-5805-8446
Michael J McConnellIntrahospital Infections Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain.ORCID https://orcid.org/0000-0003-1028-381X

Funding

Agència de Gestió d'Ajuts Universitaris i de Recerca 2023-PROD-00034Fundació "la Caixa" LCF/TR/CI23/56000019Generalitat Valenciana CIDEIG/2022/028Instituto de Salud Carlos III F19III/00006Instituto de Salud Carlos III MPY-380/18Instituto de Salud Carlos III MPY 516/19
6 · The paper itself

Abstract

Development of vaccines against Klebsiella pneumoniae has potential to prevent infections in both community and hospital settings and reduce associated mortality and morbidity worldwide. DNA vaccines represent a promising approach given their stability, safety, design flexibility and cost-effectiveness for rapid production. In this study, two plasmid backbones, namely the commercial pVAX1 and the newly designed PLASMIVAX (containing additional CpG motifs), were tested to develop two DNA vaccines targeting the MrkA fimbrial subunit from K. pneumoniae. MrkA is highly conserved among K. pneumoniae and was expressed and secreted in vitro, fused to immunostimulatory elements, by both DNA vaccines following transfection of HEK-293T cells. Immunogenicity was assessed in mice by measuring antibody levels (IgM, IgG, IgG1, IgG2a and IgG3) after intramuscular immunization with three doses of 50 μg of each DNA vaccine. Efficacy of protection was established in a sepsis infection model. The pVAX1-MrkA DNA vaccine elicited the most robust antibody response and protection against K. pneumoniae infection (80%, p = 0.0373), while the PLASMIVAX-MrkA DNA vaccine protected at a lower rate (30%, p = 0.0163), consistent with lower post-immunization antibody titers elicited by this vaccine. This study reveals that DNA plasmid properties strongly influence immunogenicity and vaccine efficacy and highlights the potential role of MrkA as a vaccine antigen and DNA platforms as a valuable tool for developing vaccines against multidrug-resistant bacteria.

Indexed as

Bacterial ProteinsBacterial VaccinesKlebsiella InfectionsKlebsiella pneumoniaePlasmidsSepsisVaccines, DNAAnimalsAntibodies, BacterialDisease Models, AnimalFemaleHEK293 CellsHumansImmunogenicity, VaccineImmunoglobulin GMiceAntibodies, BacterialBacterial ProteinsBacterial VaccinesImmunoglobulin GVaccines, DNADNA vaccineKlebsiella pneumoniaemultidrug resistanceplasmid backbonevaccine

Identifiers

PMID42634491
PMCPMC13501101

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.