Organ transplant breakthrough sees scientists successfully convert lungs to become ‘universal’ and work in ANY patient regardless of their blood type
- Canadian researchers successfully converted human lung from type A to type O
- ‘Universal’ organ exposed to the blood of a type O patient and was not rejected
- Team hope to launch a human clinical trial within the next two years
Scientists have moved one step closer to creating ‘neutral’ organs that can be transplanted into any patient — regardless of their blood type.
A team of Canadian researchers successfully converted the blood group of a human lung from type A to the universal type O. The organ was then exposed to the blood of a type O patient in a laboratory to simulate a real transplant and was not rejected.
Dr Stephen Withers, a biochemist who co-led the experiment, said it has ‘opened a gateway to create universal blood-type organs’ in the future.
The team hope to launch a human clinical trial within two years, which could see a converted organ transplanted into a patient.
Currently the blood group of donors and recipients must be a match or rapid and potentially-fatal rejection can occur. It means those with rare blood types like O or B wait up to 20 times longer for transplants than those with more common types.
Longer waits have a direct impact on survival, with type O lung transplant patients 20 per cent more likely to die while in the queue.
Dr Aizhou Wang, one of the surgeons involved in the experiment, treats a human lung with enzymes that changes the organ’s blood type
Blood type is determined by the presence of molecules on the surface of red blood cells, known as antigens.
That is why blood transfusions can only be done with two patients from the same group — or from donors with type O blood, which do not have any antigens.
Man receives a PIG heart in world first op
A dying man became the first patient in the world to get a heart transplant from a genetically-modified pig last month.
Terminal heart failure sufferer David Bennett underwent the nine-hour experimental procedure at the University of Maryland Medical Center in Baltimore.
Surgeons used a heart taken from a pig that had undergone gene-editing to make it less likely that his body’s immune system would reject the organ.
A month later, Mr Bennett, 57, is still alive and is being monitored closely by doctors.
Bennett, a labourer, knew there was no guarantee the risky operation would work but was too sick to qualify for a human organ.
A day before his pioneering surgery, Bennett said it was ‘either die or do this transplant’, adding: ‘I want to live. I know it’s a shot in the dark, but it’s my last choice.’
Prior attempts at such transplants – or xenotransplantation – have failed, largely because patients’ bodies rapidly rejected the animal organ.
Notably, in 1984, ‘Baby Fae’ — who was born with a rare heart condition — lived 21 days with a baboon heart.
These molecules are also found on the blood vessels of organs and can trigger an immune response if they are foreign to the body.
The latest study, published in the journal Science Translational Medicine, looked at two sets of lungs from type A patients.
One was treated with enzymes that clear antigens from the surface of the organ while the other was used as a control.
Both sets of lungs were then exposed to type O blood with high concentrations of immune cells that target type A antigens.
The treated lungs were well tolerated while the others showed signs of rejection.
The team hope to move to human studies within 12 to 18 months.
Dr Marcelo Cypel, a surgeon at the Canadian University Health Network and lead author of the study, said: ‘With the current matching system, wait times can be considerably longer for patients who need a transplant depending on their blood type.
‘Having universal organs means we could eliminate the blood-matching barrier and prioritize patients by medical urgency, saving more lives and wasting less organs.’
The group of enzymes used in the study were identified in 2018 and are found in the human gut.
They have the ability cut sugars from the A and B antigens on red blood cells, converting them into universal type O cells.
The latest experiment involved a machine known as the Ex Vivo Lung Perfusion (EVLP) System, which pumps nourishing fluids through organs and warms them to body temperature, simulating the human body.
Last month, a genetically modified pig heart was transplanted into a terminally ill heart failure patient using the same technique with enzymes.
Around 7,000 people are on the UK Transplant Waiting List and at least one person dies every day while waiting for a match.
In the US, an average 20 people die each day waiting for one to become available.
But the problem has become a worldwide phenomenon, as the population gets older there is more demand.
Blood type has a direct impact on how long someone will wait, even for the most crucial organ transplants – like a heart.
The NHS says group O patients wait on average 479 days for a heart compared to 150 days for group B, 87 days for group A and 24 days for type AB.