This is an aquatic flatworm called a planarian with a bellyful of green fluorescent bacteria. Planarians posses a truly enviable trait: immortality. Astonishingly, they can't die of old age because of an extraordinary ability to regenerate. Not only that, they can resist bacteria that are harmful, even fatal, to humans. Striving to understand the planarian’s impressive immune defence, researchers have infected the planarian with bacteria that are dangerous in humans, such as the species that causes tuberculosis, and studied the genes the worm activated. They identified 18 genes that make it resistant to these harmful organisms and focused on one gene in particular, MORN2. Later, the team switched on this MORN2 gene in a type of human white blood cell (a macrophage). These white blood cells could efficiently eliminate the TB-bacteria, bringing the possibility of new ammunition to fight against bacteria-borne diseases. But oh, to be a planarian!
Written by Nick Kennedy
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.