In a world first, researchers have launched a clinical trial of lab-grown red blood cells for transfusion into another person. These manufactured blood cells were grown from stem cells from donors, for transfusion into volunteers in the RESTORE randomised controlled clinical trial.
If our trial is successful, it will mean that patients who currently require regular long-term blood transfusions will need fewer transfusions in future, helping transform their care
Professor Cedric Ghevaert, chief investigator
If the technique is proven safe and effective, manufactured blood cells could in time revolutionise treatments for people with blood disorders such as sickle cell and rare blood types. It can be difficult to find enough well-matched donated blood for some people with these disorders.
To produce the lab-grown blood cells, stem cells are first magnetically extracted from a normal 470ml blood donation. These stem cells are then coaxed into becoming red blood cells. Over the three week process, an initial pool of about half a million stem cells generates 50 billion red blood cells.
Chief Investigator Professor Cedric Ghevaert, Professor in Transfusion Medicine and Consultant Haematologist at the University of Cambridge and NHS Blood and Transplant, said: “We hope our lab grown red blood cells will last longer than those that come from blood donors. If our trial, the first such in the world, is successful, it will mean that patients who currently require regular long-term blood transfusions will need fewer transfusions in future, helping transform their care.”
Professor Ashley Toye, Professor of Cell Biology at the University of Bristol and Director of the NIHR Blood and Transplant Unit in red cell products, said: “This challenging and exciting trial is a huge stepping stone for manufacturing blood from stem cells. This is the first-time lab grown blood from an allogeneic donor has been transfused and we are excited to see how well the cells perform at the end of the clinical trial.”
The trial is studying the lifespan of the lab grown cells compared with infusions of standard red blood cells from the same donor. The lab-grown blood cells are all fresh, so the trial team expect them to perform better than a similar transfusion of standard donated red cells, which contains cells of varying ages.
Additionally, if manufactured cells last longer in the body, patients who regularly need blood may not need transfusions as often. That would reduce iron overload from frequent blood transfusions, which can lead to serious complications.
The trial is the first step towards making lab grown red blood cells available as a future clinical product. For the foreseeable future, manufactured cells could only be used for a very small number of patients with very complex transfusions needs. NHSBT continues to rely on the generosity of donors.
Co-Chief Investigator Dr Rebecca Cardigan, Head of Component Development NHS Blood and Transplant and Affiliated Lecturer at the University of Cambridge, said: “It’s really fantastic that we are now able to grow enough red cells to medical grade to allow this trial to commence. We are really looking forward to seeing the results and whether they perform better than standard red cells.”
Thus far, two people have been transfused with the lab grown red cells. They are well and healthy, and were closely monitored with no untoward side effects were reported. The amount of lab grown cells being infused varies but is around 5-10mls.
Donors were recruited from NHSBT’s blood donor base. They donated blood to the trial and stem cells were separated out from their blood. These stem cells were then grown to produce red blood cells in a laboratory at NHS Blood and Transplant’s Advanced Therapies Unit in Bristol. The recipients of the blood were recruited from healthy members of the NIHR BioResource.
A minimum of 10 participants will receive two mini transfusions at least four months apart, one of standard donated red cells and one of lab grown red cells, to see if the young lab-made red blood cells last longer than cells made in the body.
Further trials are needed before clinical use, but this research marks a significant step in using lab grown red blood cells to improve treatment for patients with rare blood types or people with complex transfusion needs.
Source: University of Cambridge
