Revolutionizing Healthcare: The Promise of Lab-Grown Blood

You are donating blood at Stuyvesant’s annual blood drive. You watch your blood flow through the tube. Once the donation is complete, you grab a slice of pizza and a few snacks on your way back to class, wondering how important your blood really is to the world. 

Patients undergoing surgery or suffering from traumatic injuries such as car crashes or gunshot wounds often require blood transfusions. However, these patients may not be able to receive the blood they need in time, either due to shortages or because they have rare blood types that make it difficult to find an exact blood match. Last year, the American Red Cross reported that it could only meet a quarter of hospital demand—the worst blood transfusion shortage in more than a decade. On a global scale, 61 percent of countries struggle with blood shortages. This includes every country in sub-Saharan Africa, South Asia, and Oceania. When hospitals run low on blood, physicians are forced to make decisions on who the limited blood goes to, thus denying blood transfusions to other patients. Elective surgeries––procedures that don’t involve a medical emergency––are canceled first, giving priority to more urgent surgeries that treat life-threatening conditions. 

Researchers hope to combat these shortages by creating blood artificially in laboratories. This process known as blood pharming is when scientists grow all  the components of blood in a sterile setting. The components of whole blood include red and white blood cells and platelets, all of which are important for transfusions. Last fall, researchers working with the National Health Service (NHS) Blood and Transplant organization were able to successfully grow blood. This artificially produced blood was then transfused into two people in a world-first clinical trial. Only a few spoonfuls were transfused, and no adverse effects were observed—a crucial step toward one day integrating these methods on a larger scale and preventing blood shortages. In the current production method, scientists begin with a typical donation of a pint of blood. Stem cells capable of becoming red blood cells are extracted from the blood using magnetic beads. Scientists are able to utilize these beads efficiently since the significant iron content of healthy red blood cells makes them magnetic. Over the course of three weeks, approximately half a million extracted stem cells are cultivated in a nutrient-rich medium. The initial population grows into 50 billion red blood cells, which are then filtered, resulting in 15 billion red blood cells that are fit for transfusion. 

Scientists will continue to study the effects of lab-grown blood on the human body through further clinical trials. Though the original trial only had two participants, they hope to expand the study by testing the blood in at least 10 healthy volunteers. These volunteers will receive two blood donations of five to 10 milliliters at least four months apart from each other. To test for any side effects, one blood transfusion will be a control (normal blood), while the other will be lab-grown. The blood will also contain a radioactive tracer, allowing scientists to observe how long it lasts in the body. Since red blood cells normally last for around 120 days before being replaced by stem cells, typical blood donations contain a mix of young and old red blood cells. However, lab-grown blood will be completely new, theoretically lasting for the full 120 days before needing to be replaced. When patients receive frequent transfusions, they risk developing an excessive amount of iron in their bodies. Therefore, patients who require regular long-term blood transfusions would need fewer transfusions if the radioactive tracers show that the lab-grown blood does last longer. 

Scientists also aim to eventually grow rare types of blood using rare blood donations, allowing more people to access their exact blood type for transfusions. Finding compatible donors is extremely important, as transfusions between incompatible blood types cause the immune system to attack the donated blood cells. For instance, fewer than 50 people in the world have the Rh-null blood type, making it the rarest globally. People with this blood type are only able to receive blood that is also Rh-null, making it an extremely dangerous and hard task when a transfusion is needed. If scientists are able to grow these rare types of blood, these individuals will no longer be burdened with the task of locating a donor. In contrast, people with O+ red blood cells are most common, making up 38 percent of the population. However, O- blood is known as the universal donor and has the highest demand because any blood type can receive it. 

Genetic modifications of the blood to deliver enzymes and other therapeutics to those with blood disorders is also a future goal for this new technology. For instance, the clotting and oxygen-delivery capabilities of lab-grown blood could be adjusted based on a patient’s medical needs. This may be especially helpful for individuals with sickle cell anemia, a disease that results in a chronically low oxygen level in the blood. These capabilities could also be useful for postpartum hemorrhaging, pre-surgical preparations, and transplant organ perfusion. During these operations, patients with hemophilia—the reduced ability to form blood clots—often risk excessive bleeding. The transfusion of blood modified to clot can decrease the risks that come with these procedures. 

Despite the myriad possibilities for lab-grown blood, there are also financial and technological obstacles that come with large-scale applications. Compared to the average blood donation, which only costs the NHS around $100 to manage, growing blood artificially could cost thousands of dollars per unit to produce. The harvested stem cells will also eventually exhaust themselves, limiting the amount of blood that can be grown. With more research, perhaps scientists will be able to overcome these challenges and produce volumes of lab-grown blood at a clinically viable level.