While liver transplantation is the only effective treatment for liver failure, the procedure is greatly limited by the shortage of donor organs, as an estimated 4,000 individuals who might have survived with a liver transplant die in the US every year.,  Previous efforts to build tissues from the ground up have not yet approached the goal of transplantable replacement organs, but a new breakthrough technique developed by Massachusetts General Hospital (Massachusetts, USA) brings the goal of growing transplantable replacement livers a step closer.  The team used the structural tissue of rat livers as scaffolding for the growth of tissue regenerated from liver cells introduced through a novel reseeding process involving stem cells.  They are hopeful that: " These results provide a proof of principle for the generation of a transplantable liver graft as a potential treatment for liver disease."