Intracellular Bacterial Vectors That Induce CD8+ T Cells with Similar Cytolytic Abilities but Disparate Memory Phenotypes Provide Contrasting Tumor Protection
Bibliographic record
Abstract
Induction of a functional CD8(+) T-cell response is the important criterion for cancer vaccines, and it is unclear whether acute or chronic live vectors are better suited for cancer antigen delivery. We have evaluated the tumor protective ability of two recombinant vectors, Listeria monocytogenes (LM) and Salmonella typhimurium (ST), both expressing ovalbumin (OVA). Although both vectors induced a similar OVA-specific CD8(+) T-cell response in the long term, LM-OVA induced mainly central-phenotype (T(CM), CD44(high)CD62L(high)), whereas ST-OVA induced mainly effector-phenotype (T(EM), CD44(high)CD62L(low)) cells. Both vectors induced functional OVA-specific CD8(+) T cells that expressed IFN-gamma and killed targets specifically in vivo. However, only LM-OVA-vaccinated mice were protected against B16-OVA tumors. This correlated to the ability of CD8(+) T cells generated against LM-OVA, but not against ST-OVA, to produce interleukin 2 and exhibit profound homeostatic and antigen-induced proliferation in vivo. Furthermore, adoptive transfer of memory CD8(+) T cells generated against LM-OVA (but not against ST-OVA) into recipient mice resulted in their trafficking to tumor-draining lymph nodes conferring protection. Although cytotoxicity and IFN-gamma production are considered to be the principal functions of memory CD8(+) T cells, the vaccine delivery strategy may also influence memory CD8(+) T-cell quality, and ability to proliferate and traffic to tumors. Thus, for efficacy, cancer vaccines should be selected for their ability to induce self-renewing memory CD8(+) T cells (CD44(high)IL-7Ralpha(high)CD62L(high)) besides their effector functions.
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".