The miraculous mammalian immune system deploys manifold means in order to seek and destroy bacterial and viral invaders. Staffed by a versatile team of white blood cells, there is no shortage of ingenious modes of attack. Avaricious by nature, macrophages kill their victims by eating them. They need catch only a faint whiff of infection before they make use of spindly proteins (here stained red) to propel them forward. Other proteins (shown in green) are key to their ability to ‘velcro’ themselves to surfaces (adhesion sites here stained yellow). Once the target is located, the macrophage continues to shape-shift, surrounding and engulfing the body of the invader. Safely trapped, the killer cell dispenses a fatal package of super-reactive molecules – including hypochlorite, one of the main ingredients in bleach - that will see the interloper perish once and for all.
Written by Hayley Birch
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