Life Sciences & Medicine Active Updated Sep 4, 2026
Can the aging immune system be reset?
Resetting the body's aging immune cells
Where it stands as of Sep 4, 2026
Stanford researchers found that aging jams the receptor macrophages use to clear out spent immune cells, letting inflammation leak into organs throughout the body. Blocking that one receptor, EP2, in aged mice restored 59 of 71 previously abnormal blood proteins to youthful levels, along with leaner bodies, better grip strength and sharper memory, and the same stuck pattern turned up in older human liver tissue. Blocking EP2 in a person has never been tried.
Stanford researchers found that aging jams the receptor macrophages use to clear out spent neutrophils, letting toxic cells pile up and leak inflammation into organs throughout the body. Blocking that single receptor reversed signs of aging across the liver, muscle, fat and brain in mice, and the same broken pattern turned up in aging human liver tissue.
The story so far
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Sep 4, 2026 Latest
A Stanford team led by Katrin Andreasson found that tissue-resident macrophages lose the ability to clear a second immune cell type as animals age, driving body-wide inflammation, and blocking a single receptor on those macrophages in mice produced leaner bodies, sharper memory, stronger hearts and muscles, and younger tissue in the brain, liver, spleen, bone marrow, kidney and colon.
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Aug 15, 2026
Mount Sinai researchers found that deleting the protein TIMP2 from mouse microglia caused the cells to rapidly take on hallmarks of aging, senescence, sluggish debris clearing and heightened inflammatory signaling, while injecting TIMP2 into already-old mice reversed the effect, shifting microglia away from their pro-inflammatory state and restoring their debris-clearing function.
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Aug 9, 2026
Stanford researchers led by postdoctoral scholar Julia Belk traced shared DNA mutations between blood stem cells and brain tissue to show that bone marrow sends a large wave of immune cells into the aging human brain that become microglia, a process not seen in mice or other lab primates, published July 30 in Nature.
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Jul 17, 2026
Stanford researchers found that the hormone prostaglandin E2 jams macrophages' ability to clear spent neutrophils through a receptor called EP2, and blocking EP2 in aged mice restored 59 of 71 previously abnormal blood proteins to youthful levels, along with leaner body composition, better grip strength and sharper memory. The team found the same pattern of stuck neutrophils and inflammation in older, diseased human liver tissue.
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