Summary
ABO and Rh antigens on red cells determine compatible donors, since mismatches trigger agglutination.
In depth
Type O red cells lack A and B antigens (universal donor for red cells); AB plasma lacks anti-A and anti-B (universal plasma donor). Rh-negative mothers with Rh-positive fetuses can develop antibodies, prevented by anti-D injection. Karl Landsteiner discovered ABO in 1901.
Antibodies against missing antigens exist naturally. Cross-matching tests recipient serum against donor cells. Rh incompatibility can cause haemolytic disease of the newborn.
Remember: Type O negative is the universal red cell donor.
The ABO system was found by Karl Landsteiner in 1901 (Nobel Prize 1930). People naturally make antibodies against the A or B antigens they lack, because of exposure to similar structures on gut bacteria. A mismatched transfusion leads to agglutination and haemolysis. Rhesus D-negative mothers carrying a D-positive baby can make anti-D antibodies, which in later pregnancies can cause haemolytic disease of the newborn; anti-D immunoglobulin given after birth prevents this.
Over 40 blood group systems exist. Blood is cross-matched before transfusion. Platelet and plasma transfusions have their own compatibility rules, and group O negative is used in emergencies. Blood types differ in frequency among populations.
Remember: type O is the universal red cell donor, and AB the universal plasma donor, but full cross-matching is still done.
Frequently asked questions
What is Blood Groups and Transfusion?
ABO and Rh antigens on red cells determine compatible donors, since mismatches trigger agglutination.
Which area of biology covers Blood Groups and Transfusion, and how advanced is it?
Blood Groups and Transfusion is one of the 52 topics in Immunology & Disease. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Transplant Rejection, Hypersensitivity Types, Complement System.
Can you give an example of Blood Groups and Transfusion?
A mismatched transfusion causes haemolysis.
What should I learn before Blood Groups and Transfusion?
Work through the Beginner topics in Immunology & Disease first, such as Immune System, Viruses, Innate Immunity, then return to Blood Groups and Transfusion. Intermediate topics assume the Beginner vocabulary.
What topics are related to Blood Groups and Transfusion?
The closest topics to Blood Groups and Transfusion are Transplant Rejection, Hypersensitivity Types, Complement System, Antibodies. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Blood Groups and Transfusion?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Blood Groups and Transfusion. To practise the whole of Immunology & Disease, use the Immunology & Disease quiz.
How is Blood Groups and Transfusion different from Transplant Rejection?
Blood Groups and Transfusion: ABO and Rh antigens on red cells determine compatible donors, since mismatches trigger agglutination. Transplant Rejection: Recipient immune cells recognise donor MHC as foreign, requiring matching and immunosuppression. Read both side by side and note what each one explains.
How should I study Blood Groups and Transfusion step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Transplant Rejection and explain the difference aloud. Finally, take the Immunology & Disease quiz and come back to this page for any question you miss.