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Published on: December 7, 2019
T-cell activation under hypoxic conditions enhances IFN-gamma secretion
Jessica Roman1, Tirumalai Rangasamy, Jia Guo
1University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642-8692, USA.
American Journal of Respiratory Cell and Molecular Biology
|April 18, 2009
Summary
Hypoxia, a low-oxygen state, enhances CD4(+) T-cell cytokine secretion, particularly IFN-gamma. This effect is mediated by the transcription factor NRF2, highlighting hypoxia as a key regulator of T-cell responses.
Area of Science:
- Immunology
- Cellular Biology
- Physiology
Background:
- Secondary lymphoid organs and peripheral tissues often exhibit hypoxic microenvironments.
- Hypoxia influences T-cell metabolism and survival, but its impact on T-cell activation is less understood.
Purpose of the Study:
- To investigate the effect of hypoxia on CD4(+) T-cell activation and effector cytokine secretion.
- To elucidate the molecular mechanisms underlying hypoxia-mediated modulation of T-cell responses.
Main Methods:
- Mouse CD4(+) T cells were stimulated in vitro under normoxic (20% O2) and hypoxic (1% O2) conditions.
- Cytokine secretion was measured, and experiments involved genetically modified cells (e.g., IFN-gamma receptor-deficient, NRF2-deleted) and promoter reporter assays.
Main Results:
- Hypoxia significantly augmented the secretion of effector CD4(+) T-cell cytokines, most notably IFN-gamma.
- This enhancement was independent of mouse strain and not mediated by effects on IFN-gamma consumption or proximal promoter activity.
- Deletion of the transcription factor NRF2 attenuated the hypoxia-induced increase in cytokine secretion.
Conclusions:
- Hypoxia is a significant modulator of effector cytokine secretion in CD4(+) T cells.
- The transcription factor NRF2 plays a crucial role in mediating the effects of hypoxia on T-cell cytokine production.
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