Developmental trend of artificial blood (artificial red blood cells)

Regarding research on artificial blood, the "Field of Artificial Blood Development" was inaugurated in 1997, supported by the Ministry of Health and Welfare Grant-in-Aid for Health Science Research, for intensive research activities in the three sub-fields, i.e., artificial red blood cells, artificial platelets, and artificial antibodies. Developed by molecular assembling technology, artificial red blood cells, in the form of hemoglobin vesicles comprising hemoglobin encapsulated with a phospholipid bilayer as a highly efficient oxygen carrier, are now under investigation in laboratory animals to verify their function and safety. These vesicles are characterized by a particle size about 1/30 that of erythrocytes, preservability in a liquid state for 2 years at room temperature, and a sufficient retention time in circulating blood without evoking activation of platelet or complements. The hemoglobin vesicles have proven both to possess a high oxygen-carrying capacity in massive exchange transfusion studies in rodents, and to be remarkably safe, based on blood biochemical tests and pathologic findings in load-dosing and repeated-dose studies. Their noticeable safety against active oxygen has also been demonstrated. A joint industry, government, and university research project on artificial red blood cells is in progress with the present objective of developing a complement to transfusion therapy for emergency lifesaving.