High Concentrations of Etanercept Reduce Human Islet Function and Integrity

Area of Science:

• Immunology
• Transplantation Biology
• Islet Cell Biology

Background:

• Etanercept, a TNFα inhibitor, is commonly used in islet transplantation protocols.
• No prior dose-response studies exist for Etanercept's effect on human islets.

Purpose of the Study:

• To determine the optimal dose of Etanercept for human islet culture.
• To investigate Etanercept's effects under normoxic and hypoxic conditions.

Main Methods:

• Human islets were cultured with varying Etanercept concentrations (2.5-40 µg/mL).
• Cultures were maintained in normoxic (21% O2) or hypoxic (2% O2) atmospheres.
• Islet viability, function, cytokine production, mitochondrial function, and reactive oxygen species were assessed.

Main Results:

• 5 µg/mL Etanercept optimally preserved islet integrity in normoxia.
• Doses ≥10 µg/mL Etanercept impaired islet viability and insulin release.
• In hypoxia, 5 µg/mL Etanercept significantly improved islet survival, function, and reduced inflammatory markers.

Conclusions:

• Etanercept exhibits a narrow therapeutic window for human islet culture.
• Dosage optimization is crucial for Etanercept use in islet transplantation.
• Findings inform strategies for drug delivery in islet scaffolds.