A laboratory-grown blood sample has been given to people as part of a first clinical trial in the world, UK researchers claim.
To test how the substance performs in the body, tiny amounts (equivalent to a few spoonfuls) are being used.
People who donate regularly will make up the bulk of blood transfusions.
The ultimate goal is to create vital but rare blood groups that are difficult to obtain.
These are essential for patients who need regular blood transfusions to treat conditions like sickle cell anaemia.
The body will reject the blood if it isn’t a perfect match and then the treatment will fail. This tissue-matching level goes beyond the traditional A, B, AB, and O blood types.
Professor Ashley Toye from the University of Bristol said that some groups are “really, truly rare” and that there might only be 10 people who can donate.
There are currently only three units in stock of the “Bombay”, a blood group first identified in India, across the UK.
This research project brings together teams from London, Bristol, Cambridge, London, and NHS Blood and Transplant. The research focuses on red blood cells, which carry oxygen from the lungs into the rest of your body.
- They begin with a normal blood donation (around 470ml).
- Magnetic beads can be used to extract flexible stem cells capable of turning into a red blood cell.
- These stem cells can be encouraged to multiply in large numbers in labs
- They are then guided to red blood cells
It takes approximately three weeks to complete the process. A pool of about half a million stem cell precursors results in 50,000,000 red blood cells.
These red blood cells are then filtered to obtain around 15 billion red blood cell that are in the correct stage of development for transplant.
Prof Toye said to me, “We want as much blood as we can in the future. So the vision in my mind is a room full machines producing it continuously from a normal donation.”
Two people took part in the first phase of the trial. The goal is to test blood in at most 10 healthy volunteers. They will receive two blood donations, one normal and one lab-grown, at least four month apart.
Scientists can track the radioactivity in blood by tagging it with radioactive substances, which are often used in medical procedures.
It is hoped that the lab-grown blood will prove to be more potent than usual.
Red blood cells last approximately 120 days before needing to be replaced. The typical blood donation will contain a mixture of old and young red blood cells. Lab-grown blood, on the other hand, is 100% fresh so it should last for 120 days. Researchers believe this will allow for smaller donations and more frequent donations in the future.
There are however significant technological and financial challenges.
The NHS spends around PS130 on an average blood donation. Although the NHS will not disclose how much, growing blood will be more expensive.
Another problem is that the stem cells harvested eventually become exhausted, which reduces the number of blood vessels that can be grown. To produce clinically relevant volumes, it will require more research.
Dr Farrukh Shah is the medical director for transfusion at NHS Blood and Transplant. He said that “This world-leading research laid the foundations for the production of red blood cells that can safely and securely be used to transfuse patients with conditions like sickle cell.”
