Induction of Epithelial Cell Death Including Apoptosis by Enteropathogenic <i>Escherichia coli</i> Expressing Bundle-Forming Pili
Bibliographic record
Abstract
Infection with enteropathogenic Escherichia coli (EPEC) is a major cause of severe infantile diarrhea, particularly in parts of the developing world. The bundle-forming pilus (BFP) of EPEC is an established virulence factor encoded on the EPEC adherence factor plasmid (EAF) and has been implicated in both localized adherence to host cells and bacterial autoaggregation. We investigated the role of BFP in the ability of EPEC binding to kill host epithelial cells. BFP-expressing strains killed all three cell lines tested, comprising HEp-2 (laryngeal), HeLa (cervical), and Caco-2 (colonic) cells. Analysis of phosphatidylserine expression, internucleosomal cleavage of host cell DNA, and morphological changes detected by electron microscopy indicated evidence of apoptosis. The extent of cell death was significantly greater for BFP-expressing strains, including E2348/69, a wild-type clinical isolate, as well as for a laboratory strain, HB101, transformed with a bfp-carrying plasmid. Strains which did not express BFP induced significantly less cell death, including a bfpA disruptional mutant of E2348/69, EAF plasmid-cured E2348/69, HB101, and HB101 complemented with the locus of enterocyte effacement pathogenicity island. These results indicate a direct correlation between BFP expression and induction of cell death, including apoptosis, an event which may involve the targeting of host cell membrane phosphatidylethanolamine.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".