We often see in tv dramas where patients who have bleeding need blood transfusions and the blood bank is in a hurry. If the blood can also be the same as physiological saline, can be artificially manufactured, regardless of blood type, do not need strict preservation conditions, how good. Not long ago, Japan’s Asahi Shimbun reported that the Japanese research team, led by Japan’s Defense Medical University, announced that they had successfully developed an artificial blood that could save many lives, which can be preserved at room temperature for more than a year, regardless of the different blood types. At present, this artificial blood has been successfully tested in experimental rabbits.
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Artificial blood is not to restore the whole blood of the human body.
So, what exactly is artificial blood?
Artificial blood is achieved in two ways: the first is biosynthesis of red blood cells, white blood cells and platelets with full biological function, and the other is the artificial synthesis of substitutes with the main functions of red blood cells or platelets.
Zhou Jiaxi, a researcher at the Institute of Hematology of the Chinese Academy of Medical Sciences and the National Key Laboratory of Experimental Hematology at the Hospital of Hematology, points out that human whole blood is very complex and artificial whole blood is almost impossible. The artificial blood currently studied is made into certain components of the blood, more commonly artificial red blood cells and platelets.
The artificial blood developed by the Japanese team, which reported, consists mainly of artificial platelets and artificial red blood cells, and is made from a very tiny “bag” of cell membrane components called lipids, which are then filled with hemorrhagic ingredients and oxygen-carrying ingredients.
“With the development of stem cell biology and in vitro culture technology, the use of stem cell in vitro culture to amplify patient-specific blood cells (red blood cells, white blood cells and platelets) has become the mainstream research direction of artificial blood. In 2007, Japanese scientist Yukio Yamanaka and U.S. scientist Thomson transformed fibroblasts removed from the skin of the human mouth or the back of the ear into pluripotent stem cells, Zhou said. In other words, the differentiated mature cells are returned to a more primitive state and the function of differentiation into different mature cells is regained. From pluripotent stem cells can differentiate the ancestor cells of platelets – macronuclear cells, cytonuclear cell lines can provide a steady stream of platelet “mother.” Similarly, multi-energy stem cells can also add value to any cell in the blood, such as red blood cells. This artificial blood is not a synthetic blood substitute, but the body’s real “blood”, the safety is more secure.
No complications and no blood type restrictions.
In addition to alleviating the lack of blood, what are the benefits of artificial blood?
“The ideal artificial blood has the function of the corresponding components of blood, does not produce blood transfusion-related complications, and is not limited by blood type, low cost, easy to save. Zhou Jiaxi said.
Zhou Xueli, director of the blood transfusion department at the Institute of Hematology of the Chinese Academy of Medical Sciences and the Hospital of Hematology, explains that blood types refer to antigen types on the surface of blood compositions, including red blood cells, leukocytes and platelets. Human blood has antigen antibodies, if red blood cell antigen antibodies do not fit, input into the human body will occur hemolytic phenomenon. Therefore, in addition to emergencies, the import of blood products containing red blood cell components requires antibody screening and cross-matching of blood.
Artificial blood can be “genetically modified”, with gene knockout methods, knock off the blood cell surface antigen, so that blood transfusion can no longer be matched. This not only saves the trouble of blood type testing, but also solves the problem of blood transfusion for patients with rare blood types such as “Panda Blood”.
“After leaving the body, different blood compositions are preserved and validfor. Zhou Xueli said that the longest-preserved ingredient in whole blood is red blood cells, which can be preserved for up to 42 days, depending on the reservoir fluid, at a temperature of 4 degrees C. Platelets need to be saved with concussion at 22 degrees C to 2 degrees C, depending on the difference in the preservation bag, the shelf life ranges from 24 hours to 5 days, because the platelet shelf life is short, which makes it difficult to supply large quantities of emergency.
Some synthetic alternatives with certain blood functions are not limited by these preservation conditions and are generally able to be kept at room temperature for more than one year. In addition, the use of artificial blood can also effectively avoid the risk of infection with AIDS, hepatitis and other infectious diseases during blood transfusion.
Three more cans to be reached for clinical applications
At present, there is so many benefits of artificial blood is widely used in clinical practice, there is still a long way to go. Zhou Jiaxi admitted that artificial blood must meet three important conditions if it is to be used in clinical settings.
The first priority is security. Zhou Jiaxi said that many artificial blood research is still only in the animal experimental stage, and did not really enter clinical trials. Japan, the fastest-growing, has only just begun to apply for clinical trials.
The second is to achieve mass production. In the case of the Japanese team’s pedienergy stem cell preparation platelets, the whole process takes 26 days to solve the clinical emergency blood needs. And clinical blood transfusion needs to reach a certain amount to be effective, the current laboratory production of artificial blood capacity equivalent to the level of family workshops, from the factory mass production is still a long way away.
The third is to reduce costs. The cost of platelets currently prepared with pluripotent stem cells is much higher than the cost of donated platelets and tens of thousands of times higher than the cost of donating platelets. “If it takes $100,000 to lose a bag of platelets, then this artificial blood makes no sense. Zhou Jiaxi said.
Although the road is long, but with the emergence of multi-energy stem cell technology, I believe that with the continuous development of science and technology, in the near future, artificial blood will be able to achieve low-cost mass production like physiological saline, to solve the problem of tight blood supply, while playing an important role in the treatment of various blood diseases.