Different blood groups and their significance

for undergraduate class

1. DIFFERENT BLOOD GROUPS AND THEIR SIGNIFICANCE

2. HISTORY Karl Landsteiner Discovered ABO Blood group system in 1901 Discovered Rh factor in 1930 along with Alexander S. Wiener

3. Landsteiners Rule If an antigen / agglutinogen is present on the red cell membrane of an individual, the corresponding antibody/agglutinin will be absent in the plasma. If an antigen / agglutinogen is absent on the red cell membrane of an individual, the corresponding antibody / agglutinin will be present in the plasma.

4. MAJOR ABO Rh (Rhesus) MINOR Lewis Duffy Kidd Kell Lutheran

5. ABO BLOOD GROUPING Blood group A If you belong to the blood group A, you have A antigens on the surface of your RBCs and B antibodies in your blood plasma. Blood group B If you belong to the blood group B, you have B antigens on the surface of your RBCs and A antibodies in your blood plasma.

6. Blood group AB If you belong to the blood group AB, you have both A and B antigens On the surface of your RBCs and no A or B antibodies at all in your blood plasma. BLOOD GROUP O If you belong to the blood group O (null), You have neither A or B antigens on the Surface of your RBCs but you have both A and B antibodies in your blood plasma .

7. Principle of blood grouping Blood grouping is done on the basis of agglutination. Agglutination means the collection of separate particles like RBCs into clumps or masses. Agglutination occurs if an antigen is mixed with its corresponding antibody which is called i soagglutinin , i.e. Occurs when A antigen is mixed with anti-A or when B antigen is mixed with anti-B. Almost all normal healthy individuals above 3-6 months of age have “ naturally occurring antibodys ” to the ABO antigens that they lack . These antibodys termed naturally occurring because they were thought to arise without antigenic stimulation

8. RBC precursor structure

9. FormaTION OF H ANTIGEN The H antigen is the foundation upon which A and B antigens are built A and B genes code for enzymes that add a sugar to the H antigen Immunodominant sugars are present at the terminal ends of the chains and confer the ABO antigen.

10. FOR MATION OF A ANTIGEN FOR MATION OF B ANTIGEN

11. BOMBAY BLOOD GROUP RBCs with no H, A, or B antigen (patient types as O) Bombay RBCs are NOT agglutinated with anti- A , anti-B, or anti-H (no antigens present)

12. Bombay serum has strong anti-A, anti-B and anti-H, agglutinating all ABO blood groups What blood group would you use to transfuse this patient?? ANOTHER BOMBAY Group O RBCs cannot be given because they still have the H antigen you have to transfuse the patient with blood that contains No H antigen

13. R h GROUPING It is the most important blood group system after ABO. All Rh antigens are controlled by 2 genes – RHD gene– determines expression of D , RHCE – encodes for C ,c and E ,e . RhD is a strong antigen (immunogenic) and other antigen are less antigenic than D and are of less clinical significance. Therefore , in practice Rh negative and Rh positive depends on presence of D antigen on the surface of red cells which is detected by strong anti-D serum. Occasionally, anti – C,E,c,e may develop in case of pregnancy or transfusion.

14. Unlike ABO system there is no naturally occuring antibodies against R h antigens in R h negative individuals. Immune ANTIBODYS develop against Rh antigen after exposure to it following transfusion or pregnancy. It can be detected by enzyme treatment or coombs test( antiglobulin test) SIGNIFICANCE: Rh incompatibility results in haemolytic tranfusion reaction. Haemolytic disease of newborn .

15. IMPORTANCE OF BLOOD GROUPING AND Rh TYPING   In blood transfusion Haemolytic disease of newborn . Paternity dispute Medicolegal issues Immunology,genetics Susceptibility to various diseases (blood group O – peptic ulcer, Blood group A – gastric ulcer)

16. Minor blood groups and significance 1.Duffy blood group- lack glycoprotein DARC, which is receptor for plasmodium vivax . So this blood group patients are not susceptible to malaria. 2. Kell blood group- very immunogenic . increased hemolytic disease of new born. 3.Kidd blood group- increased hemolytic transfusion reaction.

17. UNIVERSAL DONOR AND RECIPIENT UNIVERSAL DONOR GROUP O N either A or B antigens UNIVERSAL RECEIPIENT GROUP AB Patient has no Anti A/Anti B present. Cannot lyse any transfused cell