Scientists Engineer Super Macrophages That Clear Dead Cells to Fight Inflammation

Chronic inflammation underlies many age-related diseases, often worsened when immune cells fail to properly clear dead cellular debris. This accumulation creates a vicious cycle where uncleared dead cells trigger more inflammation, contributing to conditions like fatty liver disease and atherosclerosis.

Researchers at Shandong University engineered a synthetic version of TREM2, a crucial receptor that helps macrophages detect and consume dead cells. During inflammation, enzymes damage natural TREM2 receptors, impairing this cleanup process. The team created a cleavage-resistant TREM2 (CRT) that maintains function even under inflammatory conditions.

Using specialized lipid nanoparticles, scientists delivered CRT genetic instructions directly to macrophages in living mice. These enhanced macrophages showed superior ability to clear apoptotic cells compared to normal macrophages. In mouse models of metabolic-dysfunction-associated steatohepatitis (fatty liver disease) and atherosclerosis, CRT-enhanced macrophages significantly reduced dead cell accumulation and inflammation.

This approach represents a novel therapeutic strategy targeting the root cause of many inflammatory diseases - defective cellular cleanup. By restoring and enhancing macrophage function, this technology could potentially treat various age-related conditions characterized by chronic inflammation and poor debris clearance. The findings suggest broad applications for diseases where apoptotic cell accumulation drives pathology, offering hope for more effective treatments for inflammatory conditions that currently have limited therapeutic options.