The ABO and Rh Blood Group Systems
Human blood is categorized into different types based on the presence or absence of certain antigens on the surface of red blood cells and antibodies in the blood plasma.
ABO System
The ABO system classifies blood into four main types:
- Type A: Has A antigens on red blood cells and B antibodies in plasma
- Type B: Has B antigens on red blood cells and A antibodies in plasma
- Type AB: Has both A and B antigens on red blood cells and no A or B antibodies in plasma
- Type O: Has neither A nor B antigens on red blood cells but has both A and B antibodies in plasma
Rh System
The Rh system is based on the presence or absence of the Rh D antigen:
- Rh+ (positive): Has the Rh D antigen on red blood cells
- Rh- (negative): Does not have the Rh D antigen on red blood cells
Blood Transfusion Compatibility
For safe blood transfusions, the donor's blood must be compatible with the recipient's blood. If incompatible blood is transfused, the recipient's antibodies can attack the donor's red blood cells, causing a potentially fatal transfusion reaction.
Transfusion Rules:
- Type O- is the universal donor (can donate to any blood type)
- Type AB+ is the universal recipient (can receive from any blood type)
- Recipients can receive blood from their own type or from compatible types
- The recipient's antibodies must not react with the donor's antigens
The Nobel Prize Connection
In 1930, Karl Landsteiner was awarded the Nobel Prize in Physiology or Medicine for his discovery of human blood groups in 1901. This discovery revolutionized medicine by making blood transfusions safer and saving countless lives.
Later, in 1940, Landsteiner was also part of discovering the Rh blood group system, further advancing our understanding of blood compatibility.