Blood groups and Rh incompatibility
In addition to their fucntion of oxygen transport, red blood cells have antigen (protein) on their suface. The significance of these antigens is that the bloods of different people have different antigenic and immune properties so that antibodies in the plasma of one blood will react with antigens on the surfaces of the red cells of another blood type. Two antigens—type A and type B—occur on the surfaces of the red blood cells in a large proportion of human beings. It is these antigens (also called agglutinogens because they often cause blood cell agglutination) that cause most blood transfusion reactions. Two genes, one on each of two paired chromosomes, determine the O-A-B blood type. The six possible combinations of genes are OO, OA, OB, AA, BB, and AB.
Along with the ABO blood type system, the Rh blood type system is also important when transfusing blood. The development of plasma agglutinins responsible for causing transfusion reactions differ between the ABO system and the Rh system. In Rh system, the person must first be massively exposed to an Rh antigen, such as by transfusion of blood containing the Rh antigen, before enough agglutinins to cause a significant transfusion reaction will develop while in the ABO system the agglutinins develop spontaneously.
At the end of the lesson students will be able to learn;
1. Blood groups (ABO system) and its significance
2. Rh system
3. Transfusion reactions
4. Hemolytic disease of newborn
5. Tissue and Organ transplantation
