Human blood that flows through our circulatory system mainly contains white cells, red cells, platelets, and plasma. It is responsible for many functions such as carrying oxygen and essential nutrients to the lungs and tissues, clot formation, maintaining the amount of blood in the body, transporting immune cells to different parts of the body, and temperature regulation of the human body.
During the World Wars, emergency surgical procedures, and later when HIV was discovered, there was an increased need for safe and efficient blood transfusion along with screening and cross-matching. Moreover, in conditions such as hemorrhagic shock, there is a need to store blood for a long time and transfuse it quickly.
What are the Applications?
Scientists are in a quest to create a blood substitute that would fulfill the requirements of human blood. In theory, artificial blood is an alternative blood product that can perform the essential life-sustaining task of oxygen and carbon dioxide transportation but has not immunological and coagulative functions. Although trials are going on, none of the products have been FDA-approved as an oxygen-carrying blood substitute.
Artificial blood is available in the form of hemoglobin-based oxygen carriers and perfluorocarbon emulsions. Perfluorocarbon emulsions are made of inert substances that replace hydrogen and fluorine. On the other hand, hemoglobin-based oxygen carriers contain hemoglobin-derived products.
One of the most significant artificial blood features is that it does not cause immunological reactions in the recipient's body, unlike natural blood. It also has the slightest chance of developing an infection during transfusion. Unlike natural blood, artificial blood has a long shelf life of up to 2 years at room temperature if stored after freeze-drying.
Statistics show that there is definitely a shortage of blood globally. Hence, artificial blood supply could take care of this shortage and save lives. This product is mainly indicated in scenarios where a large amount of blood is needed, and there is less time for cross-matching. Faster delivery of oxygen by artificial blood in case of an emergency is another beneficial feature. Patients with bone marrow disease and elderly patients also are potential groups that can be benefitted.
KaloCyte is a startup that promotes a blood substitute, ErythroMer, which acts as a human red blood cell by doing the function of oxygen transportation. Reports say that NASA is interested in this product for their space stations and mission to Mars as ErythroMer can be stored as a freeze-dried powder. The addition of water reactivates this product to give it blood-like fluidity.
Megakaryon is a startup that works on producing an alternative to blood donations by developing platelets in vitro from induced pluripotent stem cells. They are collaborating with Kyoto University's Center for iPS Cell Research and Application.
Nano Sanguis is a startup that develops a blood substitute with a synthetic oxygen carrier that is stable for at least one year of storage. The product is physiologically inert, with essential minerals and biomimic microcapsules containing oxygen.
Biopure Corporation is that deals in oxygen therapeutics (blood substitutes) such as Hemopure (HBOC-1) [hemoglobin glutamer-250 (bovine)] for human use, and Oxyglobin (HBOC-301) therapeutics. These are made to transport oxygen to the body's tissues.
Other key players in the field of artificial blood include FLUORO2 Therapeutics, North Field Laboratories, Sangat Corporation, Baxter, Green Cross Corp., Alliance Pharmaceutical Corporation, Alpha Therapeutic Corp., and others.
What the future holds
Shortage of blood during emergency medical procedures and surgeries can pose severe complications. Moreover, with an aging population globally, finding blood donors is becoming more difficult as most of them are not suitable as donors due to ailments or medical history. This creates an 'institutionalized blood thirst' that will propel the market upwards in the years to come.
It is speculated that five years from now, the artificial blood business will become worth many billions if a product can be developed that can have not only an oxygen-carrying capacity of natural blood but also other properties such as immunity and clotting.
It is not as easy as it may sound- to find an exact substitute for human blood with all its goodness, but we are hoping that soon there would be a product that could replace human blood in care of a surgical emergency, severe blood loss following accidents, or in geographical areas where blood is not available when needed. Such a development would eliminate the risk of infections due to improper blood donation and the screening system to control the illegal human blood sale.