From the time we are born until adulthood, most of our cells are growing. Their replication, movement and repair are all part of a major construction job that makes us what we are. But growth is also a difficult balance – unnecessary growth in certain tissues can lead to cancer, while a lack of growth in ‘settled’ or differentiated tissues can leave holes that might have mended easily during early development. Originally taken from the lining of a human throat, these cells have been treated with chemicals which coaxed them out of retirement, to start growing again. After a few days, the cells were turned back into ‘throat cells’ (outlined here in red with their DNA stained blue), simulating transplantation in another human body. They quickly ‘remembered’ to develop mucus proteins (shown in green) and a carpet of microscopic hairs called cilia (in white) which sweep dirt from human lungs.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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