Brain's cleaning cells may pull the rubbish out of nerve cells, animal study hints
Brain immune cells called microglia pull bags of waste out of nerve cells. They bite off a tiny piece of the nerve cell's long arm and leave the rest intact, seen in lab dishes and in living animal brains.
Why it matters
Nerve cells are shaped like very long thin trees, and their arms can stretch far from the main body. Rubbish made far out along those arms normally has to travel all the way back to be broken down, which is slow and can go wrong. This work suggests neighbouring cells can simply carry the rubbish away instead, which would be a neat solution. Waste that piles up inside nerve cells is a feature of illnesses like Alzheimer's disease, so this may matter one day. But the study tested no disease, and it was done in animals and in cells grown in dishes. Human brains may respond differently.
Who's behind it: R. Pepper, S. Watanabe and colleagues, Johns Hopkins University School of Medicine.
Summary by the Lemma AI · how we grade