IFN-α Induces Heterogenous ROS Production in Human β-Cells.

Area of Science:

• Immunology
• Endocrinology
• Molecular Biology

Background:

• Type 1 diabetes (T1D) is a complex autoimmune disease influenced by genetic and environmental factors, such as viral infections.
• Interferon alpha (IFN-α), a key cytokine in antiviral responses, is implicated in immune system regulation.
• Human beta cells, responsible for insulin production, are central to T1D pathogenesis.

Purpose of the Study:

• To investigate the effect of IFN-α on human beta cell physiology, specifically reactive oxygen species (ROS) production.
• To identify molecular characteristics of beta cells susceptible to IFN-α-induced ROS.
• To compare IFN-α response in beta cells from healthy donors versus T1D donors.

Main Methods:

• Intravital microscopy utilizing a beta-cell-specific ROS biosensor (RIP1-GRX1-roGFP2) in transplanted human islets.
• In vitro IFN-α treatment of human islets followed by analysis of superoxide production.
• Flow sorting of IFN-α-treated human islets and subsequent RNA sequencing.
• Comparison with existing single-cell RNA-Seq datasets from the Human Pancreas Analysis Program (HPAP).

Main Results:

• A subset of human beta cells demonstrated acute ROS production in response to IFN-α.
• Healthier donor islets exhibited a higher number of ROS-accumulating cells compared to others.
• In vitro IFN-α stimulation led to heterogeneous mitochondrial superoxide production in human islets.
• RNA sequencing revealed enrichment of inflammatory and immune response genes in ROS-producing cells.
• Upregulated genes in ROS-producing cells were more prevalent in control beta cells than in T1D beta cells.

Conclusions:

• IFN-α stimulates mitochondrial ROS production in healthy human beta cells.
• This IFN-α-induced ROS production may indicate a more effective antiviral response in healthy beta cells.
• The findings suggest a potential difference in beta cell response to viral triggers between healthy individuals and T1D patients.