P0078 PP DELINEATING THE ROLE OF THE FAS PATHWAY DURING HELICOBACTER PYLORI VACCINATION
Bibliographic record
Abstract
Introduction: Helicobacter pylori (H. pylori) causes chronic gastritis, peptic ulcers and is associated with gastric cancers. Studies in animal models indicate that a vaccine against H. pylori to prevent these complications is feasible. However the factors in the effector immune response which result in protection against H. pylori infection remain unclear. Apoptosis plays an essential role in the immune system and one mechanism by which immune cells undergo apoptosis occurs through binding of the Fas ligand to the Fas receptor. Hypothesis: The Fas apoptotic pathway is involved in the host immune response during successful vaccination against H. pylori. Methods: C57BL/6 and gld (Fas ligand deficient) mice were divided into 3 groups: control (n=5), infected with H. pylori SS1 strain (n=10), and vaccinated with H. pylori sonicate and cholera toxin (CT) prior to infection (n=18). The degree of bacterial colonization, and gastritis was determined in gastric tissue sections using a standard scoring system. The degree of apoptosis of gastric epithelial cells was measured using the TUNEL (terminal transferase mediated biotinylated dUTP nick end labeling) assay. Lymphocytes isolated from the spleen were stimulated with H. pylori antigens, and production of IFN-gamma, IL-5 and IL-10 measured by immunoassay. Results: Following vaccination and subsequent H. pylori infection, bacterial colonization was undetectable in 78% of C57BL/6 mice. In marked contrast only 18% of vaccinated gld mice remained uninfected. A similar degree of inflammation and apoptosis in the gastric mucosa was detected in both infected and vaccinated C57BL/6 and gld mice. IL-5 and IL-10 but not IFN-gamma increased in response to vaccination in the C57BL/6 mice (p<0.001). However, increases in IL-5, IL-10 and IFN-gamma were not detected in vaccinated gld mice. Conclusion: Vaccination against H. pylori is not effective in the Fas ligand deficient mice. Alteration in the degree of apoptosis of gastric epithelial cells does not explain the failure. However the inability of gld mice to mount effective cytokine responses to H. pylori vaccination might explain our findings. Taken together these results indicate that the Fas mediated pathway plays an important role in the modulation of immunity during H. pylori vaccination.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.009 | 0.002 |
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 source (direct Gemma or distilled Codex), 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".