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Purification of the Membrane Compartment for Endoplasmic Reticulum-associated Degradation of Exogenous Antigens in Cross-presentation
Published on: August 21, 2017
Mitochondrial complex I activity promotes antigen cross-presentation in dendritic cells
Sofía C Khouili1,2, Elena Priego1,3, Ignacio Heras-Murillo1
1Immunobiology Laboratory. Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain.
Mitochondrial complex I (CI) is crucial for dendritic cell (DC) antigen cross-presentation. Restoring the NAD+/NADH ratio in CI-deficient DCs rescued this essential immune function.
Area of Science:
- Immunology
- Mitochondrial Biology
- Cell Metabolism
Background:
- Mitochondrial metabolism influences immune cell signaling.
- The precise role of individual electron transport chain complexes in dendritic cell (DC) function is not fully understood.
Purpose of the Study:
- To investigate the role of mitochondrial complex I (CI) in dendritic cell (DC) function, specifically antigen cross-presentation.
- To elucidate the metabolic mechanisms linking CI integrity to DC antigen cross-presentation.
Main Methods:
- Utilized NDUFS4-deficient mice to study the impact of CI dysfunction in DCs.
- Assessed mitochondrial respiration, glycolytic shift, endosomal escape, and antigen presentation pathways.
- Measured NAD+/NADH ratio, ATP levels, neutral lipid storage, and lipid peroxidation.
- Intervened by restoring the NAD+/NADH ratio to evaluate rescue effects.
Main Results:
- NDUFS4 deficiency in DCs impaired mitochondrial respiration without a compensatory glycolytic shift.
- CI dysfunction in DCs limited antigen cross-presentation by affecting endosomal escape.
- Lowered NAD+/NADH ratio and ATP levels were observed in NDUFS4-deficient DCs.
- Restoring the NAD+/NADH ratio rescued antigen cross-presentation defects in both NDUFS4- and NDUFS2-deficient DCs.
Conclusions:
- Mitochondrial complex I integrity is a critical checkpoint for DC antigen cross-presentation.
- The NAD+/NADH ratio and associated redox metabolism are key regulators of this process.
- Findings reveal a direct link between mitochondrial CI function and effective immune surveillance via DCs.
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