Evidence map›Paper›PMID 30253765›Full record

ArticleRespiratory research2018

PrtA immunization fails to protect against pulmonary and invasive infection by Streptococcus pneumoniae.

Chen-Fang Hsu, Chen-Hao Hsiao, Shun-Fu Tseng, Jian-Ru Chen, Yu-Jou Liao, Sy-Jou Chen, Chin-Sheng Lin, Huey-Kang Sytwu, Yi-Ping Chuang

Open access · goldAbstract read
In one paragraph

Article in Respiratory research, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
1.1field-weighted citation impact, top 21% 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

4 citing papers in PubMed, 8 citations in OpenAlex.

  1. Review
  2. Article
  3. Review
  4. Extracellular Pneumococcal Serine Proteases Affect Nasopharyngeal Colonization.Frontiers in cellular and infection microbiology · 2020
    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

9 authors at 4 institutions in 1 country.

Chen-Fang HsuDepartment of Pediatrics, Chi Mei Medical Center, Tainan, Taiwan.
Chen-Hao HsiaoCheng Hsin General Hospital, Taipei, Taiwan.
Shun-Fu TsengDepartment and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.
Jian-Ru ChenDepartment and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.
Yu-Jou LiaoDepartment and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.
Sy-Jou ChenDepartment of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Chin-Sheng LinDivision of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Huey-Kang SytwuDepartment and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.
Yi-Ping ChuangDepartment and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan. ypchuang@mail.ndmctsgh.edu.tw.
National Defense Medical Center · TWChung Shan Medical University · TWNational Taiwan University · TWTaipei Medical University · TW

Funding

Cheng Hsin General Hospital Foundation CH-NDMC-105-8Chi Mei Medical Center CMNDMC10108Ministry of Science and Technology, Taiwan NSC 102-2320-B-016 -013-MY2National Defense Medical Research MAB102-91National Defense Medical Research MAB106-109
6 · The paper itself

Abstract

backgroundStreptococcus pneumoniae is a respiratory pathogen causing severe lung infection that may lead to complications such as bacteremia. Current polysaccharide vaccines have limited serotype coverage and therefore cannot provide maximal and long-term protection. Global efforts are being made to develop a conserved protein vaccine candidate. PrtA, a pneumococcal surface protein, was identified by screening a pneumococcal genomic expression library using convalescent patient serum. The prtA gene is prevalent and conserved among S. pneumoniae strains. Its protective efficacy, however, has not been described. Mucosal immunization could sensitize both local and systemic immunity, which would be an ideal scenario for preventing S. pneumoniae infection.

methodsWe immunized BALB/c mice intranasally with a combination of a PrtA fragment (amino acids 144-1041) and Th17 potentiated adjuvant, curdlan. We then measured the T-cell and antibody responses. The protective efficacy conferred to the immunized mice was further evaluated using a murine model of acute pneumococcal pneumonia and pneumococcal bacteremia.

resultsThere was a profound antigen-specific IL-17A and IFN-γ response in PrtA-immunized mice compared with that of adjuvant control group. Even though PrtA-specific IgG and IgA titer in sera was elevated in immunized mice, only a moderate IgA response was observed in the bronchoalveolar lavage fluid. The PrtA-immunized antisera facilitated the activated murine macrophage, RAW264.7, to opsonophagocytose S. pneumoniae D39 strain; however, PrtA-specific immunoglobulins bound to pneumococcal surfaces with a limited potency. Finally, PrtA-induced immune reactions failed to protect mice against S. pneumoniae-induced acute pneumonia and bacterial propagation through the blood.

conclusionsImmunization with recombinant PrtA combined with curdlan produced antigen-specific antibodies and elicited IL-17A response. However, it failed to protect the mice against S. pneumoniae-induced infection.

Indexed as

Streptococcus pneumoniaeAnimalsBacterial ProteinsImmunizationMaleMiceMice, Inbred BALB CPhagocytosisPneumococcal VaccinesPneumonia, PneumococcalRAW 264.7 CellsBacterial ProteinsPneumococcal VaccinesCurdlanIL-17APrtAStreptococcus pneumoniae

Identifiers

PMID30253765
PMCPMC6157060
OpenAlexW2894306998

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LicenceCC BY
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Registered trials

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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.