PD-L2 May Help Aging Cells Hide From the Immune System

Researchers at Cedars-Sinai identified PD-L2 as a protein that may let damaged senescent cells escape immune clearance. Blocking PD-L2 in older mice reduced senescent cell buildup and improved insulin sensitivity, and a soluble form of the protein rises in blood with age.

• PD-L2 is higher in human senescent cells than younger cells and rises with age
• Mice lacking PD-L2 accumulated fewer senescent cells and had better insulin sensitivity
• Blocking the protein improved insulin sensitivity in older mice
• Soluble PD-L2 in blood could serve as a marker for senescent cells without biopsies