Omics · study · 2026
Accessory fimbrial subunits and PPAD are necessary for TLR2 activation by Porphyromonas gingivalis
Listed in NCBI GEO
Porphyromonas gingivalis is an oral pathogen that promotes dysbiosis by quenching the bactericidal activity of the host immune system while maintaining chronic inflammation, leading to periodontitis.
Description
This involves the secretion of virulence factors such as P. gingivalis peptidyl arginine deiminase (PPAD), which converts the C-terminal Arg residues of bacterial and host-derived proteins and peptides into citrulline. We have previously shown that PPAD activity and major fimbriae (containing FimA) are necessary for P. gingivalis to activate Toll-like receptor 2 (TLR2).
TLR2 is an important component of the innate immune system and plays a predominant role in the recognition of P. gingivalis by host cells. Here, we extend those findings to show that P. gingivalis strains deficient for PPAD and fimbriae induced almost identical transcriptional profiles in infected primary human gingival fibroblasts (PHGFs), but these differed substantially from the transcriptome elicited by the wild-type ATCC 33277 strain.
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Apparently, PPAD-modified fimbriae trigger the host cell response to P. gingivalis, as confirmed by showing that the proinflammatory host cell response mediated by TLR2 is dependent on PPAD activity and the presence of fimbriae, with type I fimbriae as the most potent TLR2 activators. We also found that PPAD-modified accessory fimbrial subunits (FimC, FimD, and FimE) alone or in combination are TLR2 ligands in a reporter cell line.
Although FimA polymerization to form the fimbrial shaft was not required for TLR2 activation, the secretion and proteolytic maturation of FimA were necessary for signaling by accessory Fim proteins. This was supported by showing that the proinflammatory activation of PHGFs is dependent on PPAD and accessory fimbrial subunits. We conclude that accessory fimbrial subunits are modified by PPAD and stimulate the response to P. gingivalis infection in a TLR2-dependent manner.
Links
Get the data
- GEO FTP directory ftp.ncbi.nlm.nih.gov/geo/series/GSE332nnn/GSE332616 ↗
download · from NCBI GEO
Where it is published
- GEO accession page ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE332616 ↗
landing page · from NCBI GEO
Documentation and papers
- PRJNA1468674 ncbi.nlm.nih.gov/bioproject/PRJNA1468674 ↗
project · from NCBI GEO
- PubMed 37347653 pubmed.ncbi.nlm.nih.gov/37347653 ↗
publication · from NCBI GEO
Topics
- Stated by source
- Expression profiling by high throughput sequencing · Homo sapiens
- From keywords
- Life Sciences
Provenance · 1 source records, 7 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| NCBI GEO | GSE332616 | 15 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · NCBI GEO | connector:ncbi_geo@1.0.0 | |
| concepts[field].local:field:life-sciences | mapping · NCBI GEO | connector:ncbi_geo@1.0.0 | |
| concepts[method].geo_series_type:expression-profiling-by-high-throughput-sequencing | source · NCBI GEO | connector:ncbi_geo@1.0.0 | /gdstype |
| concepts[organism].NCBITaxon:9606 | source · NCBI GEO | connector:ncbi_geo@1.0.0 | /taxon |
| description | source · NCBI GEO | connector:ncbi_geo@1.0.0 | /summary |
| publication_date | source · NCBI GEO | connector:ncbi_geo@1.0.0 | |
| title | source · NCBI GEO | connector:ncbi_geo@1.0.0 | /title |