What is the principle of ABO blood group identification?

ABO blood group identification is based on the principle of antigen-antibody reaction. When the corresponding antibody meets the corresponding antigen, the agglutination reaction will be visible to the naked eye. The common method to judge a person's blood type is to take a person's peripheral blood, which is less than two slides, and then drip it with liquid containing anti-A serum and anti-B serum respectively to observe whether the blood slides have agglutination reaction. If it reacts with the liquid of anti-A serum but does not react with anti-B antibody, it is blood type A, if it only reacts with anti-B antibody, it is blood type B. If it reacts with anti-A antibody and anti-B antibody at the same time, it is blood type AB, and if there is no agglutination reaction, it is blood type O.

ABO blood group identification is used to test our blood type. Some components contained in our blood can distinguish our blood type. For this classification, we now have at least 20 classification systems, ABO blood group system is one of them, and it is also the most common blood classification. In addition to ABO blood group system, we will also use RH blood group system. For ABO blood group system, we mainly divide it into type A, type B, type O and type AB, while for RH blood group system, it is divided into negative and positive.

The main factor to distinguish ABO blood type is to look at the antigen type contained on the surface of mature red blood cells in this person's blood. If there is an antigen on the surface of our red blood cells, we call this person type A blood. Similarly, red blood cells of type B blood only contain B antigen. There are both A antigen and B antigen on the surface of red blood cells, which is what we usually see as AB blood. Type O blood is called universal blood because neither A antigen nor B antigen is expressed on the surface of red blood cells, which makes almost all blood types accept their blood transfusion without worrying about rejection.