New research shows that the cells responsible for protecting the brain from infection and inflammation are also responsible for repairing the system of defenses that separates the brain from the rest of the body.
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The new study, which was published today in the Proceedings of the National Academy of Sciences, reveals that the brain's immune system, specifically cells called microglia, play a central role in the process of repairing damage to the BBB.
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Performing experiments in mice, Nedergaard and her colleagues observed that when small holes where made in the BBB, nearby microglia were rapidly mobilized and set about repairing the breach. In most instances, the integrity of the BBB was restored within 10 to 30 minutes.
The team identified a receptor called P2RYX12 that was responsible for activating the microglia and directing them to the site of the damage. This finding is significant because the same receptor is also present on platelets and is one of the targets of blood thinning drugs such as Plavix.
http://medicalxpress.com/news/2016-01-brain-immune-cells-key-blood-brain.html#nRlv