It is very common to hear the following question: What is your blood type? When referring to blood type, we generally want to know which group of the ABO system that person's blood fits into. But, after all, what is the ABO system?
→ What is the ABO system?
O ABO system brings together the blood groups discovered in the early 20th century by Karl Landsteiner. In his studies, the researcher noticed that there was a blood incompatibility between some people and, when there was a mixture of some types of blood, agglutination occurred. Landsteiner and his team then rated the blood in four types: A, B, AB and O. Then came the ABO system.
→ Agglutinins and agglutinogens
When studying blood types, Landsteiner noticed the presence of two substances: one located in the blood plasma and the other present in the red blood cell membrane. The substances in plasma were called agglutinins, and those that were present in the wall of the red blood cells were called agglutinogen. These agglutinins are nothing more than antibodies, which react with the agglutinogens in red blood cells.
In the ABO system, there are two types of agglutinogens and two types of agglutinins. Agglutinogens can be A or B, and agglutinins can be Anti-A or anti-B. Below are the agglutinogens and agglutinins present in each of the blood types.
blood group |
agglutinogen |
agglutinin |
THE |
THE |
Anti-B |
B |
B |
anti-A |
AB |
AB |
- |
O |
- |
Anti-A and anti-B |
→ blood transfusions
Recognizing the presence of agglutinins and agglutinogens, it is clear that some blood types are not compatible with others. When putting A blood into a person with blood type B, the anti-A agglutinin agglutinates the donor's red blood cells. This will also happen if B blood is placed in a person of type A blood who has anti-B antibodies. AB blood does not have agglutinins in its plasma and therefore can receive blood from people of any blood type. A person with blood type O cannot receive blood of any other blood type, as it has anti-A and anti-B agglutinin.
We can conclude that blood type O is a universal giver, since it has no agglutinogen, however, it can only receive type O blood. AB blood, in turn, is universal receiver, for he can receive blood of any kind, but he can only donate to himself.
To learn more about blood, go to: What is the HR factor?
By Ma. Vanessa dos Santos
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/biologia/o-que-e-sistema-abo.htm
