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The City of Cherbourg is mobilizing for blood donation. For a month, she posted in her streets the modalities to make an appointment at the donation center of the French Blood Establishment. (© City of Cherbourg-en-Cotentin)
Donating blood is essential to save other lives.
But do you really know what is your blood made of and what’s the point of giving it away?
Small biology course.
Blood is living tissue made up of red blood cells, white blood cells and platelets, bathed in a fluid called plasma.
He plays an essential role in many vital functions like breathing, nutrition, defense, regulation …
The different elements of blood bear individual identity marks. These are molecules, antigens, which vary from person to person.
These differences define blood groups.
Why is my blood not compatible with all the others?
The most important features for transfusion are the ABO and Rhesus systems, which determine blood compatibility between two individuals.
Humans have antigen A, antigen B, both, or neither. They are thus classified in one of the 4 blood groups A, B, AB or O.
Each blood group also has antibodies that will destroy incompatible cells. For example, groups A, will have B antibodies. Mixing the two blood groups can therefore have dramatic consequences for the transfused.
Finally, the Rhesus system indicates the presence or absence of the D antigen which determines whether an individual is of rhesus positive (+) or negative (-).
The combination of the two systems allows classification in 8 blood groups: A +, A-, B +, B-, AB +, AB-, O + and O-.