In the first clinical study of its kind in the world, a team of British researchers gave patients blood "grown" in the laboratory to test its behavior within the body. In the (prudent) experimentation small amounts of blood are tested, the equivalent of a couple of spoons.
The target? Produce viable but ultra-rare, difficult-to-obtain blood types. Blood typing is needed for people who regularly receive blood transfusions for conditions such as sickle cell anemia. If the blood doesn't match exactly, the body begins to reject it and the treatment fails. This level of tissue matching goes beyond the known blood groups A, B, AB and O. Prof Ashley Toye, from the University of Bristol, notes that some groups are “really, really rare” and that “there may only be 10 people in the country” able to donate. A blood group first identified in India, for example (it is called “Bombay” for a reason) has only 3 units of blood available in the whole of the UK.
This clinical trial represents a promising step forward in the potential production of laboratory-grown blood that could be used to treat patients with rare blood types.
A goal that has been pursued for some time
An effective "blood substitute" has been in the sights of scientists for years. Without starting too far away, the first "modern" steps on this path date back to 2012. In 2019 the state of research suggested that we would have had to wait until at least 2024 for the first applications of an "artificial" blood suitable to cover only some functions of the "real" one. With these latest advances we have moved forward decisively.
And it is a very important thing. Because to understand and cure diseases, we need to study blood and its components. By finding a substitute for human blood, we can do this without risking the lives of donors. Also, as mentioned, by having an artificial or biological replacement for human blood, we can create a safe and reliable supply of blood for transfusions.
How is laboratory-grown blood obtained?
In summary, the blood is collected through a process that takes about three weeks, and starting from about half a million stem cells, 50 billion red blood cells are obtained, then "skimmed" into 15 billion, the right quantity (and the right stage) for a transplant.
We want to produce as much blood as possible in the future, so the vision in my head is a room full of machines that continuously produce it from a normal blood donation
Ashley Toye, University of Bristol
The first two people who took part in the trial will receive two donations of 5-10 ml at least four months apart: one of normal blood and one of laboratory-grown blood. The project aims to test cultured blood in at least 10 healthy volunteers.
Towards a "reinforced" blood, but the challenges are many
Hopefully, lab-grown blood will be more potent than normal blood.
Red blood cells normally last around 120 days before needing to be replaced - a typical blood donation contains a mix of young and old red blood cells, while lab-grown blood is all freshly produced. For this reason, the researchers suspect (and hope) that this may allow for smaller and less frequent donations in the future.
However, the financial and technological challenges are significant. Cultivating blood will cost much more than just donating - a crucial step that will make research more difficult until you are able to lower costs by extending this procedure.
“The potential benefit for difficult-to-transfuse patients is very significant,” says Dr Farrukh Shah, medical director of transfusions at NHS Blood and Transplant. Over 7 million sufferers of sickle cell anemia alone (and the disease is constantly increasing). But the game is worth the candle: this research could end up saving or improving the lives of hundreds of thousands of people around the world.
