ArticleInfection and immunity2007
Modulation of adherence, invasion, and tumor necrosis factor alpha secretion during the early stages of infection by Streptococcus pneumoniae ClpL.
Article in Infection and immunity, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 17 papers.
What it found
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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.
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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.
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Who cites it
17 citing papers in PubMed, 29 citations in OpenAlex.
- 3' UTR-mediated regulation of a protein chaperone by the pspA mRNA in Streptococcus pneumoniae.Nucleic acids research · 2026Article
- Pneumococcal disease burden in high-risk older adults: Exploring impact of comorbidities, long-term care facilities, antibiotic resistance, and immunization policies through a narrative literature review.Human vaccines & immunotherapeutics · 2024Review
- Otitis media: recent advances in otitis media vaccine development and model systems.Frontiers in microbiology · 2024Review
- Significance of Individual Domains of ClpL: A Novel Chaperone fromBiochemistry · 2020Article
- The pneumococcal two-component system SirRH is linked to enhanced intracellular survival of Streptococcus pneumoniae in influenza-infected pulmonary cells.PLoS pathogens · 2020Article
- TLR4 mediates pneumolysin-induced ATF3 expression through the JNK/p38 pathway in Streptococcus pneumoniae-infected RAW 264.7 cells.Molecules and cells · 2015Article
- TREK-1 Regulates Cytokine Secretion from Cultured Human Alveolar Epithelial Cells Independently of Cytoskeletal Rearrangements.PloS one · 2015Article
- Ethanol-induced alcohol dehydrogenase E (AdhE) potentiates pneumolysin in Streptococcus pneumoniae.Infection and immunity · 2015Article
- Streptococcus pneumoniae ClpL modulates adherence to A549 human lung cells through Rap1/Rac1 activation.Infection and immunity · 2014Article
- ClpL is required for folding of CtsR in Streptococcus mutans.Journal of bacteriology · 2013Article
- SP0454, a putative threonine dehydratase, is required for pneumococcal virulence in mice.Journal of microbiology (Seoul, Korea) · 2012Article
- The role of ClpP in protein expression of Streptococcus pneumoniae.Current microbiology · 2012Article
- Decrease in penicillin susceptibility due to heat shock protein ClpL in Streptococcus pneumoniae.Antimicrobial agents and chemotherapy · 2011Article
- Virulence attenuation of Streptococcus pneumoniae clpP mutant by sensitivity to oxidative stress in macrophages via an NO-mediated pathway.Journal of microbiology (Seoul, Korea) · 2010Article
- Characterization of the Streptococcus pneumoniae BgaC protein as a novel surface beta-galactosidase with specific hydrolysis activity for the Galbeta1-3GlcNAc moiety of oligosaccharides.Journal of bacteriology · 2009Article
- Article
- Review
Corrections and comments
- Erratum issued
Authors and funding
7 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Heat shock proteins (HSPs) play a pivotal role as chaperones in the folding of native and denatured proteins and can help pathogens penetrate host defenses. However, the underlying mechanism(s) of modulation of virulence by HSPs has not been fully determined. In this study, the role of the chaperone ClpL in the pathogenicity of Streptococcus pneumoniae was assessed. A clpL mutant adhered to and invaded nasopharyngeal or lung cells much more efficiently than the wild type adhered to and invaded these cells in vitro, as well as in vivo, although it produced the same amount of capsular polysaccharide. However, the level of secretion of tumor necrosis factor alpha (TNF-alpha) from macrophages infected with the clpL mutant was significantly lower than the level of secretion elicited by the wild type during the early stages of infection. Interestingly, treatment of the human lung epithelial carcinoma A549 and murine macrophage RAW 264.7 cell lines with cytochalasin D, an inhibitor of actin polymerization, increased adherence of the mutant to the host cells. In contrast, cytochalasin D treatment of RAW 264.7 cells decreased TNF-alpha secretion after infection with either the wild type or the mutant. However, pretreatment of cell lines with the actin polymerization activator jasplakinolide reversed these phenotypes. These findings indicate, for the first time, that the ClpL chaperone represses adherence of S. pneumoniae to host cells and induces secretion of TNF-alpha via a mechanism dependent upon actin polymerization during the initial infection stage.
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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.