Japanese researchers have created a universal, long-lasting artificial blood that works for all blood types, promising to transform emergency medicine and address donor shortages. Clinical trials are underway to ensure this lab-made blood is safe and effective for human use by 2030, potentially revolutionizing trauma care and saving lives in battlefields and remote areas.
In a world grappling with aging populations and blood donor shortages, scientists in Japan have achieved a milestone: developing artificial blood that can be transfused into any patient regardless of blood type . This innovation, spearheaded by Professor Hiromi Sakai at Nara Medical University, is virus-free and has a remarkable shelf life of up to two years at room temperature . Unlike traditional donated blood, which must be matched by type and typically expires in about 42 days under refrigeration, the new artificial blood remains stable and ready-to-use for vastly longer periods.
The artificial blood was born out of necessity. Japan, like many countries, faces a decline in blood donations as its population ages, raising concerns about future blood supply . In emergencies – from natural disasters to battlefield injuries – obtaining the right blood type in time can mean the difference between life and death. “It is difficult to stock a sufficient amount of blood for transfusions in such regions as remote islands,” explains Associate Professor Manabu Kinoshita of Japan’s National Defense Medical College, a co-developer of the blood. “The artificial blood will be able to save the lives of people who otherwise could not be saved.” The universal compatibility of this blood eliminates the delay of blood typing and cross-matching, allowing medics to administer transfusions immediately, anywhere .
How Does Artificial Blood Work?
At the heart of this innovation is a hemoglobin-based oxygen carrier packaged in a clever way. The Japanese team’s artificial blood contains hemoglobin vesicles (HbV) – tiny liposome (fat membrane) particles about 250 nanometers in diameter that encapsulate purified human hemoglobin . Hemoglobin is the iron-rich protein normally found inside red blood cells (RBCs) that binds oxygen. By extracting hemoglobin from donated human blood (specifically from expired blood units that would otherwise be discarded) and wrapping it in a synthetic lipid membrane, the researchers created microscopic artificial RBCs that can transport oxygen to tissues .
What makes these artificial cells “universal” is that their external membranes contain no blood-type antigens – the markers that differentiate A, B, O, and Rh blood groups . In natural blood, those antigens on RBC surfaces can trigger immune reactions if the wrong type is given. The lab-made blood’s vesicles are essentially blank envelopes carrying oxygen, so the body doesn’t recognize them as “A” or “B” or any type. By removing the natural cell membranes that define blood type, the product becomes compatible with all patients . This means no need for cross-matching or typing in an emergency; a truly universal blood substitute is at hand.
The artificial blood formula isn’t just red cells: it also includes a platelet substitute to help with clotting. The Japanese team added liposome-based hemostatic nanoparticles – in essence, artificial platelets – into the mix . In natural blood, platelets are cell fragments that clump together to form clots and stop bleeding, but they are delicate and expire after only about 4–5 days at room temperature. By incorporating a stable clotting component, the artificial blood can both carry oxygen and help seal wounds. In the lab, the researchers combined these artificial RBC and platelet components with plasma (the liquid part of blood) to create a complete blood surrogate capable of both oxygen delivery and hemorrhage control.
Inside the Lab: Creating Universal Blood from Expired Donations
The raw materials for this artificial blood might surprise you: expired human blood units. Nara Medical University’s team uses blood that has passed its donation shelf-life and would normally be thrown away . From this, they isolate and purify the hemoglobin under stringent safety measures. The hemoglobin is treated and stabilized – converted to a form called carboxyhemoglobin (with carbon monoxide bound) to prevent premature oxidation, then encapsulated in a biocompatible phospholipid membrane . The liposome recipe includes common membrane molecules (like cholesterol and phospholipids) plus a polymer that extends circulation time .
After encapsulation, the hemoglobin inside the vesicles is chemically “tuned” to function like natural blood. For instance, researchers add pyridoxal-5′-phosphate (vitamin B6 derivative) to adjust hemoglobin’s oxygen affinity , ensuring it releases oxygen to tissues appropriately. The vesicles are then rendered oxygen-free (deoxygenated) and sealed in sterile bags with oxygen absorbers . This careful packaging keeps the hemoglobin in a non-oxidized, purplish state until use – indeed, the resulting artificial blood fluid is purple in color rather than red, precisely because the hemoglobin is not carrying oxygen during storage . Once infused into a patient, the hemoglobin molecules pick up oxygen and turn red, just like regular blood.
Critically, the production process includes pasteurization at 60°C and nanofiltration to remove any viruses or bacteria , making the product essentially pathogen-free . This addresses a major safety concern of donor blood: the risk of transmitting infections. By the end of the manufacturing, what emerges is a sterile, shelf-stable fluid containing functional oxygen carriers and clotting agents, but no living cells or DNA, no blood type, and no infectious risk .
Trials and Testing: From Rabbits to Healthy Volunteers
Long before reaching humans, the universal artificial blood was rigorously tested in the lab and in animals. In a landmark 2019 study published in the journal Transfusion, the Japanese team transfused the artificial blood into 10 rabbits that had suffered severe (lethal) blood loss. The results were groundbreaking: 6 of the 10 rabbits survived after receiving the artificial blood – a survival rate comparable to rabbits treated with real donated blood . In other words, the synthetic blood performed as well as natural blood at rescuing the animals from massive hemorrhage. The rabbits showed no serious side effects or abnormal clotting due to the artificial transfusion , indicating that the lab-made blood was biocompatible at least in the short term. This was a pivotal proof-of-concept that a single product could simultaneously carry oxygen and stop bleeding effectively in a living organism.
Encouraged by these results, researchers moved towards human trials. Early safety studies have been cautious and stepwise. In 2022, a first-in-human Phase 1 trial of the hemoglobin vesicle (HbV) artificial red cells was reported, involving a small number of volunteers . That initial study focused on safety and pharmacokinetics – essentially, confirming that infusing the artificial blood in humans caused no immediate harm and behaved predictably in the body. Those initial human tests paved the way for a larger Phase 1 trial that launched in 2025 at Nara Medical University Hospital .
In March 2025, the research team began administering the artificial blood to 16 healthy adult volunteers in a clinical trial . Each volunteer received a volume of 100 to 400 milliliters of the artificial blood solution, incrementally increasing to test tolerability . Importantly, these transfusions were done without any blood type matching or pre-medication, since the product is universal. The trial’s first goal is to assess safety: monitoring for any side effects, immune reactions, or organ dysfunction when moderate doses (up to 400 mL) circulate in the body . If no adverse effects are observed at the higher dose, the trial will progress to evaluating whether the artificial blood effectively delivers oxygen and improves clinical outcomes in patients – marking a shift into Phase II for efficacy testing .
Nara Medical University’s project is, so far, the first of its kind in the world. “No other country has launched a human trial of artificial blood on this scale,” notes a report on the trial . The fact that Japan’s trial uses blood derived from expired human donations is also novel – it’s a form of recycling medical waste into a lifesaving product. Should the trial succeed, Japan could take the lead in a field that has seen decades of setbacks, potentially becoming the first nation to deploy artificial blood for routine medical care .
How does this artificial blood stack up against the real thing? In several key aspects, it shows promise:
Oxygen-Carrying Capacity: The core function of red blood cells is to carry oxygen, and the artificial hemoglobin vesicles have demonstrated an ability to deliver oxygen as effectively as natural RBCs in animal models . Each hemoglobin molecule in the vesicles can bind oxygen just like in a natural cell. By tuning the hemoglobin’s chemistry (with additives like pyridoxal-5′-phosphate), researchers matched the oxygen release profile to that of normal blood . In rabbit tests, the animals that received artificial blood maintained tissue oxygenation well enough to survive severe blood loss on par with those given real blood – a strong indicator that oxygen delivery was sufficient in vivo. Clotting Ability: Thanks to the added artificial platelets, the synthetic blood can facilitate clot formation. In bleeding rabbits, no uncontrolled hemorrhage was observed after transfusion of the artificial blood , implying the platelet-mimicking component successfully aided in stopping internal bleeding. The survival of 60% of the rabbits with otherwise fatal injuries reflects that the product could both carry oxygen and clot wounds effectively, mimicking the dual role of red cells and platelets in natural blood . Additionally, no abnormal clotting (such as unwanted blood clots) was reported, indicating a balanced hemostatic response . Shelf Life and Storage: This is where the artificial blood vastly outshines natural blood. Donated human red blood cells can be stored for ~4 to 6 weeks at 2–6 °C, and platelets for just 4–7 days at room temperature . In contrast, the artificial blood **can be stored for **up to 2 years at room temperature (and up to 5 years under refrigeration) without degrading . This longevity comes from the stability of the vesicles and the absence of living cells – the product doesn’t “expire” quickly as real cells do. Such a long shelf life could enable stockpiling universal blood for emergencies and supplying areas that lack refrigeration facilities. Universal Compatibility: The artificial blood has no blood type, period. In practice, this means every unit of artificial blood is like O-negative (the universal donor type) – actually even more universal, since it also lacks Rh and other minor antigens. Compatibility testing is unnecessary . Medics can transfuse it immediately, saving precious minutes in trauma care. This contrasts with natural donor blood which, if not type O-, requires lab testing to match the patient’s blood group and screen for antibodies. Volume Efficiency: Early indications suggest that a smaller volume of artificial blood might achieve effects similar to larger volumes of whole blood. The current trial is exploring a 100 mL dose as a target effective amount for anemic patients in emergencies, which is much less than a typical unit (~400 mL) of donated blood. If proven, this could mean less volume needed to resuscitate a patient, which reduces the risk of volume overload and makes transport easier (smaller bags to carry).
The artificial blood’s performance in animal trials approached that of real blood in terms of keeping subjects alive after massive blood loss. Its shelf stability, however, is an order of magnitude better than real blood products. In practical terms, a blood bag that can sit on a shelf for years and be given to anyone could be a game-changer in emergency medicine.
Implications for Trauma Care, Battlefields, and Rare Blood Types
If ongoing trials confirm its safety and efficacy, universal artificial blood could revolutionize multiple areas of medicine. Perhaps the most immediate impact would be in trauma care and emergency response. Paramedics and military medics often operate in environments where matching blood types or keeping blood refrigerated is logistically difficult. With a stock of shelf-stable artificial blood in ambulances, helicopters, or field hospitals, first responders could start transfusions within minutes at the scene of accidents or battle injuries, greatly improving survival odds. In fact, the Nara research team has proposed protocols to equip doctor-staffed ambulances and medical helicopters with the artificial blood for use in pre-hospital critical bleeding scenarios . This could prevent patients from “bleeding out” before they ever reach a hospital.
On the battlefield, combat medics carrying universal blood packs wouldn’t need to worry about a soldier’s blood type or running out of a specific type. Every wounded soldier could receive the same artificial blood, simplifying logistics and potentially saving lives in the crucial minutes after injury. Military interest in blood substitutes has always been high for this reason – for instance, the U.S. military has invested in other experimental blood products for field use – and the Japanese breakthrough may accelerate the development of deployable blood units for defense forces worldwide.
For patients with rare blood types or antibodies, the artificial blood offers a lifeline as well. Some individuals have uncommon blood types that make finding donors challenging (or they have antibodies that make transfusions risky). A type-free blood substitute would bypass these challenges, ensuring that even patients with rare blood can get emergency transfusions without delay. It could also help in regions with ethnically diverse populations where blood type distributions vary and shortages of certain types (like Rh-negative) are common. The World Health Organization has noted that billions of units of blood are needed annually worldwide , yet many developing regions suffer chronic shortages. A portable, long-life artificial blood could be shipped to remote clinics or disaster zones, supplementing local blood supplies and overcoming infrastructure issues (no cold storage needed).
Moreover, this technology opens doors beyond human trauma medicine. The researchers suggest it could be used as a preservation solution for organ transplants, to keep donor organs oxygenated during transport . It might serve as an antidote for certain poisonings – for example, they are exploring a version of the Hb vesicles that carries carbon monoxide or nitric oxide to counteract cyanide poisoning or to reduce inflammation . In veterinary medicine, a universal blood substitute could save pets or endangered wildlife where matching donor animals is impractical. The possibilities are wide-ranging: once you have a way to package oxygen carriers and clotting factors that can be delivered to any tissue, you have a powerful tool in the medical arsenal.
Despite the excitement, caution is key. The quest for artificial blood has a long history littered with setbacks, and experts are watching closely for any signs of problems as human trials progress. Previous generations of blood substitutes, particularly hemoglobin-based oxygen carriers (HBOCs) similar in concept to the Japanese vesicles, often caused unexpected side effects. In the early 2000s, several HBOCs were found to cause organ damage, severe hypertension, or increased risk of heart attacks in patients . Free hemoglobin outside of red cells can be toxic – it can scavenge nitric oxide (leading to vessel spasm and high blood pressure) and cause oxidative damage to kidneys and other organs . The Japanese team’s approach of encapsulating hemoglobin in liposomes is specifically meant to prevent these toxic interactions by keeping the hemoglobin sheltered until it’s safely inside the bloodstream. Still, only rigorous clinical data can confirm that such adverse effects are truly avoided. The Phase I trial will carefully monitor blood pressure, kidney function, immune responses, and coagulation in volunteers who receive the artificial blood.
One ethical question is the source of the hemoglobin. Currently it comes from donated human blood (expired units). This means the product, while “artificial” in function, is still biologically derived from humans. There should be transparency with donors that even their expired blood may be used for product development. In the long run, if artificial blood is adopted widely, demand for expired or surplus blood might rise – but this is intertwined with blood donation systems. On one hand, better utilization of each donated unit (extending its use beyond expiration) is positive; on the other, if people assume an artificial supply exists, will it affect blood donor motivation? Most likely, blood donors will still be needed, as this technology doesn’t magically create hemoglobin from nothing. However, researchers are also looking into lab-grown hemoglobin or genetically engineered bacteria/yeast that could produce human hemoglobin in vats, which could eventually reduce reliance on donor blood. For now, the ethical sourcing of raw material seems sound: using waste blood that would be discarded, with thorough screening and processing to remove any pathogens .
Another consideration is long-term safety. The current studies have checked immediate outcomes, but what about a week or a month after receiving artificial blood? Does it all metabolize and clear safely from the body? The lipid vesicles will be processed by the liver and spleen like other nanoparticles, and the hemoglobin will naturally break down. Any iron released from hemoglobin needs to be properly managed by the body to avoid toxicity. The researchers will need to monitor if repeated doses cause iron overload or oxidative stress over time. So far, the trial in rabbits did not find issues in the short term , but rabbits were not followed for months after. Human trials will likely include follow-ups to see if there are any delayed effects (for example, subtle impacts on the immune system or organ function).
From a regulatory and ethical standpoint, the trial in Japan is being conducted with full oversight. Nara Medical University’s hospital manufactured the batches under pharmaceutical-grade conditions (GMP) and is conducting the trial as an investigator-initiated study with government support . This ensures that ethical guidelines for human experimentation are followed, including informed consent from volunteers and safety monitoring by independent committees. If at any point severe side effects appear, the trial would be paused. The balance of risk vs benefit is crucial: for a dying trauma patient, even a risky blood substitute could be better than certain death from exsanguination. But for elective uses, the bar for safety is much higher. As trials advance to patients with actual bleeding (perhaps in Phase II), researchers will need to decide in what scenarios the use of artificial blood is justified and safe.
One more ethical angle is equitable access. If this artificial blood proves successful, will it be made available globally, including to low-income countries that might benefit the most from a product that doesn’t require refrigeration or typing? The researchers have expressed hope that their innovation “will revolutionize the entire medical system and contribute to improving health and welfare” , even mentioning potential use in countries with inadequate blood donation systems . Achieving that will require scaling up production and keeping costs reasonable. The involvement of Japan’s governmental research agency (AMED) suggests there’s public interest in making this a broadly available solution rather than a niche product.
Voices from the Research Team
The development of universal artificial blood in Japan has been a collaborative effort across institutions like Nara Medical University, the National Defense Medical College, and others over decades. Professor Hiromi Sakai, a chemist and one of the lead scientists, has been working on blood substitutes for years. He underscores the urgency driving this project: “The need for artificial blood cells is significant as there is currently no safe substitute for red cells,” Sakai noted, highlighting how no existing product can fully replace donated blood today . His team’s determination is fueled by both the looming blood shortages and the life-saving potential in emergencies.
Associate Professor Manabu Kinoshita, an immunologist who co-authored the 2019 study, often emphasizes the practical life-saving scope of the invention. In media interviews he painted a vivid picture of remote islands and disaster zones where, currently, people die because the right blood cannot get to them in time . “With artificial blood, we will be able to save lives which could not previously be saved,” Kinoshita said, expressing confidence that their creation could plug critical gaps in care . His quote has been featured widely as it encapsulates the humanitarian promise of artificial blood – essentially ensuring no one dies for lack of the right blood.
Officials at Nara Medical University have also framed this project as an example of innovative, homegrown solution-making. At a press conference announcing the clinical trial, lead researchers explained that the artificial blood is being developed as a “special biologic product” in Japan – meaning it’s treated with the same rigor as a new drug – and that the university has set up the manufacturing and trial infrastructure on-site . This is somewhat unusual (academia producing a drug), and they called it a “flagship of academic drug discovery” . The pride in pioneering a world-first is evident, but so is a sense of responsibility: they are methodically testing it step by step. “Each carefully planned step brings us closer to that reality,” Professor Sakai said of the goal to make artificial blood an everyday tool .
The coming years will be crucial to determine whether Japan’s universal artificial blood is truly the panacea it appears to be. If the human trials prove successful, by around 2030 we may witness the first practical use of artificial blood in hospitals . Imagine trauma centers, ambulances, and field clinics stocked with universal blood bags that never expire and can be given to any patient on the spot. The ripple effects would touch many aspects of healthcare: emergency protocols would change, military combat care would improve, and blood banks might shift focus to plasma and platelets for routine use while relying on artificial RBCs for emergencies.
However, experts caution that we must remain measured in our optimism. An editorial in one medical journal noted that despite many attempts, a “reliable blood substitute” has seen “limited success” over the decades . It will take robust data to convince clinicians that this product is as safe and effective as real blood. Questions like how long the artificial blood lasts in circulation (likely a few hours to days before being cleared) and how well it perfuses tiny capillaries will need answers.
Yet, every indication so far – from the animal survival data to the early human safety tests – suggests that the Japanese team’s approach is sound and could overcome the pitfalls that halted prior substitutes. The concept of turning medical waste (expired blood) into a life-saving resource is itself a remarkable innovation in an era focused on sustainability and smart healthcare solutions .
In a broader sense, the development of universal artificial blood is a reminder of how interdisciplinary science can solve pressing problems. Chemistry (in designing the vesicles), biology (in understanding blood function), medicine (in clinical testing), and engineering (in manufacturing the product) all came together here. If successful, this artificial blood will not only save lives directly but could also alleviate pressure on blood donation systems, ensuring that surgeries and treatments dependent on transfusions have a steadier supply line.
For now, the world is watching Japan’s experiment with hopeful anticipation. A single bag of universal artificial blood represents more than just a medical product – it represents the possibility that one day, no person will be lost due to bleeding out or lack of the right blood type. As Professor Sakai and colleagues forge ahead with their trials, they carry the hope that these purple-hued blood cells will indeed become a common sight in emergency rooms and disaster kits. The coming decade will reveal if this bold vision comes to fruition, potentially opening new doors for humanity in how we safeguard the most precious fluid of life .
Sources:
Sakai H. et al. (2022). Frontiers in Medical Technology – Review of hemoglobin vesicles as artificial red cells . Kinoshita M. et al. (2019). Transfusion – Study on artificial blood in rabbits (via Asahi Shimbun report) . Nara Medical University Press Release (2024) – Announcement of Phase I trial for artificial red blood cells . Kyodo News (2024). “Clinical trial on artificial blood cells to begin in Japan” . MedIndia (2025). “Japan Launches Clinical Trial of Lab-Made Blood” (citing Japan Times and Langmuir study) . IFLScience (2019). “Japanese Scientists Create Artificial Blood…” (Interview with researchers) . Grape Japan (2019). “Artificial Blood Successfully Tested in Rabbits” . Times of India (2025). “Japan introduces universal artificial blood…” .
