A team of bioengineers has taken a step closer to the day when it will be possible to regenerate new organs from patient's own cells. The researchers have "printed" 3D patterns of blood vessel networks out of sugar that allow tissue to grow around them and then dissolve, leaving behind a hollowed-out "vascular architecture".

Once the sugar dissolves, the hollowed-out blood vessel pattern can rapidly be perfused with nutrient-rich fluid and oxygen to stop the tissue cells from dying.

(A common problem when trying to engineer thicker tissue like that of the liver, is that without a decent vascular system to deliver nutrients and oxygen and remove waste products, the cells deep inside perish.)

Although tissue engineering has made great strides in recent years, it is still impossible to recreate the complex 3D blood vessel networks that are present in naturally grown organs