Human ABO blood group system is the first found the type system, because have regular blood type antibody, so is the most important blood group system, divided into A, B, O and AB.Among them, only type O people lack of A and B antigens on red blood cells, so when recipients ABO blood group identification difficulty, can be in distribution of blood type O washing red blood cells;Type and saving lives in an emergency, with insufficient or a lack of blood, or lose a fewType O bloodIn order to a lifesaver.

But the type O blood plasma contains A resistance, resistance to B antibodies, it can sensitization or agglutination A, B, AB red blood cells, to shorten the life or destroy immediately, belongs to the transfusion taboo.So, once called the 0 type whole blood "dangerous universal blood".Someone ignores the "dangerous" two word, type O is called the "universal donor", this is wrong.