Japanese scientists have begun clinical trials for universal artificial blood. This is a significant step aimed at overcoming the global blood shortage and revolutionizing emergency medical care. The research is being conducted at Nara Medical University, in Professor Hiromi Sakai’s laboratory. Its primary goal is to create a safe and long-lasting blood substitute that can be transfused to patients of any blood type. This could save millions of lives (Azuma et al., 2022).
What is Universal Artificial Blood?
This artificial product contains hemoglobin vesicles (HbVs), microscopic, cell-like particles designed to mimic the oxygen-carrying function of red blood cells. They are made by extracting hemoglobin from expired donor blood and encapsulating it in lipid capsules.
Key Characteristics of Artificial Blood:
Universally compatible: It does not contain blood group antigens, making it suitable for anyone to receive.
Virus-free: Filtration and encapsulation eliminate pathogens.
Long-lasting: It can be stored for approximately two years, significantly longer than donor blood (Azuma et al., 2022).
Why Is This Important?
The global blood shortage is a serious problem. Approximately 118 million units of blood are collected annually, but 40% of this goes to high-income countries, which account for only 16% of the world’s population (WHO, 2024). The remaining 84% of the population is left with only 60% of the blood supply to share. As a result, low- and middle-income countries face a constant blood deficit, increasing mortality rates during traumas, surgeries, childbirth, and infectious diseases.
Universal artificial blood will be used in emergencies, crisis zones, and remote or resource-poor areas. This will significantly increase survival rates in situations where finding a compatible blood type is impossible (Newsweek, 2025).
What Stage is the Process At?
In March 2025, Nara Medical University transfused 100–400 ml of artificial blood to 16 healthy adult volunteers to assess its safety. The next stages involve testing efficacy and monitoring for potential side effects (Newsweek, 2025).
The initial clinical trial results highlighted several important aspects:
Safety: The first results showed only mild and temporary side effects, such as low-grade fever or rash, which quickly resolved (Azuma et al., 2022).
In-depth monitoring: Volunteers underwent comprehensive monitoring of vital signs, blood chemistry, and immune reactions.
Gradual dose increase: The study began with small doses, which were gradually increased. Before transfusion, volunteers received medication to reduce the risk of possible reactions.
The research is based on a Phase 1 model conducted in 2022, which demonstrated that hemoglobin vesicles are safe for oxygen transport in the human body and cause only minor and temporary self-resolving effects (Azuma et al., 2022).
What Do Experts Think?
Professor Ash Toye, an expert in cell biology from the University of Bristol, calls the Japanese research a potentially exciting step for the advancement of transfusion medicine. He notes that in the past, artificial blood products failed to prove effective due to safety concerns and insufficient oxygen delivery. However, hemoglobin vesicles have the potential to overcome these problems (Newsweek, 2025). Toye also points out that the basis of artificial blood is still human hemoglobin, so mass production will require finding new sources, such as recombinant (cell culture-derived) hemoglobin.
Future Plans
If these studies continue successfully, Nara Medical University plans to conduct larger-scale clinical trials and obtain approvals to begin using artificial blood by 2030 (Newsweek, 2025).
Should it succeed, this technology will radically transform traumatology, surgery, and the treatment of chronic diseases, not just in Japan but worldwide.
References
Azuma, H., et al. (2022). First-in-human phase 1 trial of hemoglobin vesicles as artificial red blood cells developed for use as a transfusion alternative. Blood Advances, 6(21), 5711–5713. https://doi.org/10.1182/bloodadvances.2022007977
Newsweek. (2025, June). Clinical trials to test the use of universal artificial blood are under way in Japan.
World Health Organization. (2024). Blood safety and availability.
