- Blood plays a vital role in the health of the body, however, some people have blood disorders that cause the blood to not work as it should.
- A team of researchers led by the National Health Service (NHS) Blood and Transplant unit recently launched the first clinical trial to transfuse lab-grown red blood cells into a living human.
- The researchers hope that the manufactured red blood cells will help people with rare blood types and disorders such as sickle cell disease.
Blood is an extremely important fluid in the body. It not only carries vital nutrients and oxygen to all the organs in the body, but also helps eliminate waste and fights infection.
Sometimes a person may have a blood disorder that causes their blood to not work the way it should. One of these disorders is sickle cell disease, which affects how the body works.
There are different types of blood and some are rarer than others. People can have rare blood types that make it difficult to get a transfusion if they have an accident or need surgery. For example, AB negative is the rarest blood type with only 1% of the general population that has it.
To help combat these problems, a team of researchers led by the UK’s National Health Service (NHS) Blood and Transplant Unit (NHSBT) recently released the first clinical trial to transfuse lab-grown red blood cells into a living human.
If proven safe and effective, the researchers hope these manufactured red blood cells could help people with rare blood types and blood disorders such as sickle cell disease.
Blood is made of a fluid called plasma and has three main types of cells:
Red blood cells are made in the bone marrow found in the middle of most bones. Bone marrow contains stem cells that can develop into red blood cells, white blood cells, or platelets.
The main job of red blood cells is to carry oxygen throughout the body. Red blood cells contain a protein called hemoglobin, which carries oxygen. Iron of our diet is an important component of hemoglobin.
If a person has a low red blood cell count, they may become anemic, experience fatigue, dizziness, and other problems. The most common form of anemia is iron deficiency anemia, which can be resolved through dietary changes and supplementation.
Sickle cell disease can also cause anemia. If a person has sickle cell anemia, their red blood cells, which are normally donut-shaped without perforation, become C-shaped. This prevents hemoglobin from transporting oxygen as efficiently.
The cells also become very sticky and inflexible, causing them to clump together and block blood vessels. Also, sickle cells don’t live as long as healthy red blood cells, leading to a shortage of red blood cells in the body.
A team of researchers has been working on culturing red blood cells in a laboratory setting. since 2009.
Dr Cedric GhevaertProfessor of Transfusion Medicine and Consultant Haematologist at the University of Cambridge and NHS Blood and Transplant, and co-director of this clinical trial, said they decided to grow red blood cells in a laboratory because “they knew this technology could help patients with [a] rare blood group for whom matching blood donors are difficult to find, and for patients with lifelong transfusion needs for whom red blood cells with a longer half-life would be greatly beneficial.”
For example, Dr. Ghevaert said that they can make red blood cells from stem cells that carry very rare blood groups.
According to an NHSBT spokesperson, to grow red blood cells in a laboratory setting, they use donor stem cells, which they isolate from a standard donation of whole blood. The stem cells are then placed in a nutrient solution.
For 18 to 21 days, the solution encourages the cells to multiply and become more mature cells. The researchers need 24 liters of nutrient solution and cells to filter one or two tablespoons of red blood cells.
This process results
The final product is then stored and refrigerated for up to 10 days in a small sterile vial used to store red blood cells for transfusion.
In this clinical trial, researchers will take red blood cells created in the laboratory and transfuse them into a living human.
Two people have reportedly already received lab-grown red blood cell transfusions without any complications. For this study, a minimum of 10 people will receive two mini-transfusions, one of standard donated red blood cells and one of laboratory-grown cells, at least 4 months apart.
Dr. Ghevaert said that one of the main purposes of the trial is to see if lab-grown red blood cells survive in the body as long as donated standard red blood cells:
“If they last longer in the circulation, we could transfuse our patients much less frequently, currently every 2-3 weeks, looking to extend to 6 weeks, which means they don’t accumulate as much iron. Long-term iron is toxic and it is difficult to excrete the iron that comes with transfused red blood cells, so it is important to transfuse less frequently.”
According to an NHSBT spokesperson, more trials are needed before clinical use, but this research marks a significant step in the use of manufactured blood to improve the treatment of patients with rare blood types.
“It will be years before lab-grown blood can be used outside of trials and the vast majority of patients will continue to rely on the generosity of blood donors for the foreseeable future,” the spokesperson told us.
“The introduction of new treatments can take between 5 and 15 years. This is the first of many stages of testing needed in humans.”
Today’s medical news also spoke with Dr Lewis Hsumedical director of the American Sickle Cell Disease Association and professor of pediatric hematology at the University of Illinois at Chicago about this clinical trial.
He said this new study is exciting because it is another milestone on the long road to developing lab-grown red blood cells.
“Blood for transfusion depends on people’s donations,” Dr. Hsu said when asked about the importance of being able to use lab-grown red blood cells for transfusions.
“Blood donors must be healthy and willing to donate. Donated blood has a limited shelf life and is then no longer useful. [And] the globules must be compatible so that the recipient’s immune system does not reject them”, he explained.
“Some people have rare blood types and have few compatible donors,” he continued. “This immune reaction to transfused blood is a common problem for people with sickle cell disease around the world. We have to drive additional blood drives to recruit donors for sickle cell patients and sometimes that’s not enough for blood drives.”
As for the next steps in the research, Dr. Hsu said that since the test doses in the clinical trial are one teaspoon, they are not yet useful for transfusion. In addition, lab-grown red blood cells would have to meet a number of requirements, including large-scale production capability, practical storage, and reasonable cost.
“We also note that great scientific progress has been made in reducing the need for blood transfusions, which is a strategy called
“The best surgical techniques reduce blood loss in the operating room, which includes collecting and ‘recycling’ some of the blood back into the patient. Trauma patients (car crashes, gunshot wounds, industrial accidents) have better control of coagulation function that fine-tunes how to stop bleeding and reduce transfusions. New drugs can correct anemia or reduce bleeding. And we have learned what level of anemia under what conditions can be tolerated by the body without a blood transfusion.”
– Dr. Lewis Hsu