SCIENTISTS at Edinburgh University have made a huge breakthrough after growing a fully working organ inside an animal.
The team from the Medical Research Council Centre for Regenerative Medicine at Edinburgh University successfully grew an organ called the thymus inside a mouse.
They produced the working thymus – a vital “nerve centre” located near the heart – and there are hopes the technique could provide a replacement organ for people with weakened immune systems. The thymus is a vital organ as it produces T cells which fight infections.
The landmark procedure has so far only been tested on mice and it might be another ten years before the treatment is safe enough for human patients
But for scientists it is said to be one of the “holy grails” of regenerative medicine. Professor Clare Blackburn, who led the team of scientists, said: “By directly reprogramming cells we’ve managed to produce an artificial cell type that, when transplanted, can form a fully organised and functional organ.
“This is an important first step towards the goal of generating a clinically useful artificial thymus in the lab.”
If the immune system can be compared with an army, the thymus acts as its operations base. Here, T-cells made in the bone marrow are primed to attack foreign invaders, just as soldiers are armed and briefed before going into battle.
Once deployed by the thymus, the T-cells protect the body by searching for infectious invaders such as bacteria and viruses, or dangerous malfunctioning cells, for instance from tumours. When an “enemy” is detected, the T-cells mount a co-ordinated immune response to eliminate it. The new research, published in the journal Nature Cell Biology, raises the possibility of creating a whole new functioning thymus using cells manufactured in the laboratory.
While fragments of organs, including hearts, livers and even brains, have been grown from stem cells, no one before has succeeded in producing a fully intact organ from cells created outside the body.
Dr Rob Buckle, head of regenerative medicine at the MRC, said: “Growing ‘replacement parts’ for damaged tissue could remove the need to transplant whole organs from one person to another, which has many drawbacks – not least a critical lack of donors.
“This research is an exciting early step towards that goal, and a convincing demonstration of the potential power of direct reprogramming technology, by which once cell type is converted to another. However, much more work will be needed before this process can be reproduced in the lab environment, and in a safe and tightly controlled way suitable for use in humans.”
Dr Paolo de Coppi, consultant paediatric surgeon at Great Ormond Street Hospital and head of Stem Cells and Regenerative Medicine at the Institute of Child Health, London, said: “Research such as this demonstrates that organ engineering could, in the future, be a substitute for transplantation, overcoming problems such as organ donor shortages and by-passing the need for immunosuppressive therapy.”