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Understanding the signals that elicit clearance of dead sensory cells by the immune system's macrophages in zebrafish – insights for regenerative medicine

23 October 2022

Splitting Hairs

Sometimes before repairs can begin, damage must be cleared away. Here macrophage cells (highlighted in blue) set to work engulfing and destroying dead sensory hair cells (red) inside a young zebrafish. Tackling the dead cells from all sides, the macrophages – also found in our own immune systems – are called to the scene in a curious way. Researchers find the cells receive a series of three chemical signals – each one triggering separate signalling pathways, using proteins like messengers to alter the behaviour of the cell. Ultimately, they ‘programme’ it to clean up the mess. Zebrafish regenerate their hair cells after injury, yet – for the moment – humans can’t. Studying the sequence of events after injury in the fish, scientists may find ways to mimic the process in our owns cells, improving our chances of healing hair cells essential to our hearing and balance.

Written by John Ankers

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BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

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