Red blood cell (which he later renamed to O). Landsteiner described the regular patterns in which reactions occurred when serum was mixed with red blood cells, thus identifying compatible and conflicting combinations between these blood groups. A year later Alfred von Decastello and Adriano Sturli, two colleagues of Landsteiner, identified a fourth blood group—AB. In 1959, by use of X-ray crystallography, Dr. Max Perutz was able to unravel the structure of hemoglobin, the red blood cell protein that carries oxygen. The oldest intact red blood cells ever discovered were found in Ötzi the Iceman, a natural mummy of a man who died around
Genetically engineered blood protein and a substance of choice, such as a small-molecule therapeutic agent or an antibody. The modifications leave the cells and their surfaces otherwise intact. One application is to engineer red blood cells into drug-delivery vehicles. Mature red cells carry no genetic material, potentially presenting fewer safety risks than other gene and cell therapies. Human red blood cells circulate for as long as four months, meaning they could potentially form the basis of long-term therapies. The cells move throughout body via the bloodstream and are unnoticed by the immune system. Genetically engineered blood Genetically engineered blood is blood that has