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
Red blood cell and consequently cannot divide and have limited repair capabilities. The inability to carry out protein synthesis means that no virus can evolve to target mammalian red blood cells. However, infection with parvoviruses (such as human parvovirus B19) can affect erythroid precursors, as recognized by the presence of giant pronormoblasts with viral particles and inclusion bodies, thus temporarily depleting the blood of reticulocytes and causing anemia. Human red blood cells are produced through a process named erythropoiesis, developing from committed stem cells to mature red blood cells in about 7 days. When matured, in a healthy individual these cells live in