With the exception of the liver, which has a remarkable regenerative ability, the human body is pretty inept at regrowing damaged organs and limbs – especially when compared with certain amphibians and fish. Take the zebrafish, for example, even a severed spinal cord poses nothing more than a temporary inconvenience. If cut, the spinal cord simply starts to mend itself with the formation of a cellular bridge (pictured). Scientists have now identified a crucial protein (labeled green) required for this bridge formation. And, excitingly, humans have this protein too. Moreover, the human version of the protein was found to enhance spinal cord regeneration in zebrafish whose own protein was dysfunctional. In humans, spinal cord injuries result in scars rather than bridges. If scientists could figure out why the newly identified protein is insufficient in humans to promote spinal reconnection they might discover ways to promote such healing therapeutically.
Written by Ruth Williams
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.