Medical Research Council - London Institute of Medical Sciences

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Early Warning Sign

The developing frog brain senses infection and alerts immunity

20 May 2020

Early Warning Sign

Dopamine, dubbed one of the brain’s ‘happy’ hormones, does more than just lift our mood – this neurotransmitter may in fact be crucial to survival in early stages of life. In frog embryos, dopamine signals appear to warn the young immune system about incoming bacterial infections so it can successfully fight them off. Thanks to frog embryos’ unique ability to continue developing when their brain is removed, scientists have shown that the likelihood of survival after exposure to E. coli bacteria was significantly reduced in embryos without a brain. The brain in intact embryos on the other hand, shown here in green with cranial nerves in red, acts as an early warning system, using dopamine signals to instruct immune cells to travel to the site of the infection. In future, better understanding how the brain senses these bacterial infections could help us to develop new therapies to combat them.

Written by Gaëlle Coullon

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