Science
Why Immune Cells Are Building Up in the Aging Brain, Stanford Finds
Picture the brain as a walled city that normally keeps the body's immune system locked outside. Stanford researchers now find that wall grows leaky with age, letting immune cells flood into brain tissue.
98%of immune cells the blood-brain barrier normally blocks from healthy brain tissue
The facts
- 1Stanford scientists found immune cells accumulating inside the aging brain, suggesting it is less sealed off from the body than long believed.
- 2For decades, doctors thought the blood-brain barrier, a wall of tightly joined cells, kept nearly all immune cells out of healthy brain tissue.
- 3That barrier normally blocks a large majority of circulating immune cells from crossing into the brain, according to established neuroscience research.
- 4The Stanford team observed growing numbers of immune cells collecting in brain tissue as age advanced, raising questions about the source of age-related brain inflammation.
- 5Scientists caution the immune cells' effects are still unclear, they could help repair tissue or contribute to memory decline and neurodegeneration.
Why it matters
If immune cells routinely enter the aging brain, they could drive memory loss or disease, but they might also aid repair, so future treatments must not simply block them.
Sources
- Science Daily
- Stanford University
- National Institutes of Health (NIH)
