Mitochondrial dysfunction reactivates α-fetoprotein expression that drives copper-dependent immunosuppression in...

Area of Science:

• Biochemistry
• Immunology
• Systemic Physiology

Background:

• Signaling circuits are vital for systemic physiology, but their molecular basis is often unknown, hindering metabolic disorder research.
• Mitochondrial dysfunction impacts various physiological processes, with its systemic consequences not fully understood.

Purpose of the Study:

• To identify molecular mechanisms linking mitochondrial dysfunction to systemic effects.
• To investigate the role of alpha-fetoprotein in immune response during mitochondrial stress.

Main Methods:

• Induction of mitochondrial dysfunction in murine liver and heart.
• Analysis of spleen and thymus atrophy and peripheral white blood cell counts.
• Investigation of alpha-fetoprotein's role in white blood cell death, requiring copper and CCR5.
• Assessment of alpha-fetoprotein expression following oxidative phosphorylation inhibition.

Main Results:

• Disruption of mitochondrial function activated a copper-linked signaling circuit.
• This circuit led to spleen and thymus atrophy and a deficiency in white blood cells (leukopenia).
• Alpha-fetoprotein, dependent on copper and CCR5, was identified as the cause of leukopenia by promoting white blood cell death.
• Alpha-fetoprotein expression increased in various cell types when oxidative phosphorylation was inhibited.

Conclusions:

• Bioenergetically stressed tissues may secrete alpha-fetoprotein to suppress the immune system.
• This immune suppression mechanism could account for infections seen in mitochondrial diseases or related disorders.
• The study reveals a novel signaling pathway connecting metabolic stress to immune regulation.