How close are scientists to producing artificial blood?

Scientists are exploring the production of artificial blood amid shortages of blood and the need for safe transfusions.

Millions of people die globally each year due to lack of access to blood, studies by the World Health Organization (WHO) have shown.Blood carries oxygen throughout the body and removes waste products, among many other critical functions.

Laboratory-grown blood was used on humans in the first clinical trial in 2022, particularly in patients with rare blood groups.

Scientists are also working to develop synthetic blood as part of efforts to support emergency medicine, surgery, and transfusions.

So how close are scientists to developing artificial blood?

What is artificial blood?
Artificial blood is a broad term that includes both lab-grown and synthetic blood.

Synthetic blood, which is still being studied, is a completely man-made substitute and does not contain human cells. These engineered molecules mimic the function of blood cells by transporting oxygen. It is designed mainly for emergency use or military medicine, where immediate oxygen delivery is needed but matching blood types is difficult.For example, the United States military has invested $46m in developing ErythroMer, a synthetic blood substitute designed to be universally compatible and stable without refrigeration. This product is still undergoing research and testing to establish its safety and effectiveness.

On the other hand, lab-grown blood is created by growing human red blood cells in a controlled environment outside the body.Once available, lab-grown blood cells could make the treatment of certain medical cases more effective, Cedric Ghevaert, professor of transfusion medicine at the University of Cambridge in the United Kingdom, said. For example, lab-grown platelets may be better at stopping bleeding in trauma patients compared to those given to leukaemia patients, who receive platelets to prevent bleeding rather than to stop active bleeding.

How is lab-grown blood made?
This process starts with stem cells, which are special cells that can develop into different types of cells in the body. They include red blood cells, platelets (which help blood to clot), or even skin cells, depending on where the stem cells are found and how they are stimulated.

Scientists use a specific type of cell called haematopoietic stem cells, which produce all types of blood cells, including white blood cells, red blood cells and platelets. They are found in bone marrow – the soft tissue inside bones – or in the blood of a donor.

To turn these stem cells into red blood cells, they are placed in a lab setting and exposed to growth factors – natural substances that help cells develop.