Natural Killer T Cells Are Critical for Dendritic Cells to Induce Immunity in Chlamydial Pneumonia
Bibliographic record
Abstract
RATIONALE: We previously showed an important role of natural killer T cells (NKT) in skewing the adaptive T cell immunity to Chlamydia pneumoniae (Cpn), an intracellular bacterial lung infection, but the mechanism remains unclear. OBJECTIVES: To investigate the underlying mechanism by which NKT modulate T cell responses in chlamydial pneumonia. METHODS: We examined the effect of NKT activation in modulating DC function, especially in generating protective immunity against Cpn infection using combination of NKT knockout (KO) mice and specific NKT activation approaches. MEASUREMENTS AND MAIN RESULTS: We found that NKT activation in vivo after Cpn infection induces phenotypic and functional changes in dendritic cells (DC). DC from NKT-deficient mice showed reduced CD40 expression and IL-12 production, whereas enhancing NKT activation using alpha-GalCer increased CD40 expression and IL-12 production. Co-culture of DC with NKT enhanced bioactive IL-12p70 production by DC in a CD40L-, IFN-gamma-, and cell-cell contact-dependent manner. Further, co-culture of T cells with DC isolated from infected wild-type (WT) and NKT-deficient mice induced type-1 and type-2 responses, respectively, while DC from alpha-GalCer-treated, infected mice led to enhanced type-1 responses. Moreover, upon adoptive transfer, DC from infected WT mice induced strong type-1 immunity, whereas those from knockout mice induced type-2 responses and increased disease severity upon challenge infection. CONCLUSIONS: Our results provide direct evidence of the critical role of NKT activation in the functional modulation of DC for the development of protective immunity in a clinically relevant respiratory infection.
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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) | 0.001 | 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 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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".