An islet-resident macrophage antioxidant program preserves β cell physiology

Élise Dalmas's goup whithin the IMMEDIAB lab directed by Nicolas Venteclef, in collaboration with the teams of Ann Massie from Vrije Universiteit Brussel and of Florent Ginhoux at Institut Gustave Roussy, has shed further light on the nature and function of innate immune cells residing in pancreatic islets: macrophages.

This work, led by Amélie Grosjean and Aude Jalon (co-first authors), shows that these macrophages exhibit increased pro-inflammatory, metabolic, and antioxidant activity compared to macrophages from the exocrine tissues of the pancreas surrounding the islets in mice.

The cystine-glutamate antiporter SLC7A11 drives this program, which protects islet macrophages from ferroptosis - a form of cell death regulated and initiated by oxidative disturbances - and maintains the function of insulin-producing β cells, both under physiological conditions and during oxidative stress. Human islet macrophages show a similar profile, particularly in patients with type 2 diabetes.

These results confirm the surprising phenotype of islet macrophages, ensured by SLC7A11, which helps preserve pancreatic endocrine homeostasis.

🔗 Find the link to the article in the team's key publications 

🔬 Image from Claire Leveau, postdoc in Venteclef team. Insulin (green), lectin for vessels (purple) & macrophages (gold).