Scientists have grown a liver in the lymph nodes of a pig and hope it could allow humans to grow their own replacement organs in future. 

Livers have the ability to naturally regenerate, and a sliver of the filtration organ – if transplanted – can grow to full-size and become fully-functioning. 

It is believed the lymph nodes provide a sanctuary for healthy liver cells, allowing them to slowly multiply and blossom into an 'auxiliary organ'.  

Trials in pigs shows that when the main organ was beleaguered with disease and began failing, the animal remained healthy because the auxiliary organ took over. 

Researchers from the University of Pittsburgh gave six pigs liver failure by diverting blood supply and removing a chunk of tissue.

They also took hepatocytes — the chief functional cells of the liver — from the animals and implanted them in their lymph nodes.

'It's all about location, location, location,' said senior author Dr Eric Lagasse.

'If hepatocytes get in the right spot and there is a need for liver functions, they will form an ectopic liver in the lymph node.' 

Normally, the liver can regenerate and repair itself but significant damage can overwhelm this protective mechanism.