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
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