Damaged skin normally turns black and blue as it heals. But by using immunofluorescence labelling, the act of repair can look a lot more colourful. Here pictured is an ultra-thin sheet of human foreskin that has been scratched (along the very right-hand edge) and has begun to heal. The rippling pattern of colours highlights the location of three skin cell proteins that have been tagged with red, green or blue fluorescence. The amounts of these proteins fluctuate depending on how close the cell is to the wound. During skin repair two proteins (Cx43 and CASK) appear together in some cells (red and green). Where this occurs, researchers believe they are cooperatively signalling to more epithelial cells, which in return migrate towards the wound to plug the gap in the skin’s defences.
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.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.