For years now, there has been a lot of hope surrounding stem cell research and the possibility that they can be used to make new organs to solve the transplant shortage and make cells to treat degenerative diseases. But now, we might be one step closer as researchers in the USA are planning to create new limbs from stem cells for amputees.
A surgeon at Massachusetts General Hospital is attempting to create a ‘biolimb’ to attach to a primate after successfully growing a limb for a rat. This was the first biolimb to be developed and after a few weeks it was capable of producing blood cells and muscles contracted when provided with electrical stimuli.
If the USA team can successfully fit a biolimb to a primate then they believe it can be adapted to fit humans, especially as they have already created cells to help make organs.
Currently amputees with replacement limbs have to take immuno-suppressive drugs for the rest of their lives and leaves them prone to other diseases, but if this experiment works then that would no longer be the case.
So, how can you created a new limb in the lab??
The first step is decellularisation. This is a process where a limb is stripped down to a basic scaffold of muscles, tendons, blood vessels and bones.
Cells from another being are then grown on the ‘scaffold’ in a bioreactor – a container that supplies oxygen, nutrients and electrical stimulation to the limb.
Ultimately, the limbs are restored into a fully functional form, containing the blood, bones, muscles, cartilage of the human or animal providing the stem cells. But the jump from growing a rodent’s limb to a primate’s is proving far more complicated. For example, primates have opposable thumbs, and they would need to have functioning nerve endings which are difficult to introduce. Then you need to make sure the nerve endings go to the right places, and the same with blood vessels.
So, we are still a long way off yet. But plans are underway so hopefully sometime in the not so distant future, the promise of stem cells will be one step closer and we can generate biolimbs for amputees.