Blood grouping.pdf

Blood typing A.Kewan 1  There are more than 20 genetically determined blood group classification systems known today.  The ABO and Rhesus (Rh) systems are the most important ones used for blood transfusions.  The ABO blood group system was discovered by the Austrian scientist Karl...

Blood typing A.Kewan 1  There are more than 20 genetically determined blood group classification systems known today.  The ABO and Rhesus (Rh) systems are the most important ones used for blood transfusions.  The ABO blood group system was discovered by the Austrian scientist Karl Landsteiner in 1901.  According to the ABO blood typing system there are four different kinds of blood types: A, B, AB or O. A.Kewan 2  ABO SYSTEM Blood typing : is a classification of blood based on the presence or absence of certain inherited proteins, called antigens, on the surface of red blood cells ( RBC’s ). thus, one inherits either A or B antigens called group A or B ; one inherits both A and B antigens called group AB ; one inherits neither antigen called group O. Not all blood groups are compatible with each other. Mixing incompatible blood groups leads to blood clumping or agglutination, which is dangerous for individuals. A.Kewan 3  On the other hand , a person develops a natural immunity, or antibody in their serum to the ABO antigens that are absent on their own red cells.  Thus; a group A person has anti-B antibodies, and group O person has both anti-A and anti-B antibodies , group B person has anti-A antibodies , group AB person has no antibodies. A.Kewan 4  So, The differences in human blood are due to the presence or absence of certain protein molecules called antigens and antibodies.  The antigens are located on the surface of the RBC’s and the antibodies are in the blood plasma( serum).  Antibodies (agglutinins ) in plasma are considered naturally occurring; that it produced without any known exposure to Antigen A.Kewan 5  ABO blood grouping system According to the ABO blood typing system there are four different kinds of blood types: A, B, AB or O (null). A.Kewan 6 AB0 blood grouping system 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. A.Kewan 7  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. A.Kewan 8  The ABO blood groups This table shows the four ABO phenotypes ("blood groups") present in the human population and the genotypes that give rise to them. Blood Antigens Antibodies in Serum Genotypes Group on RBCs A A Anti-B AA or AO B B Anti-A BB or BO AB A and B Neither AB O Neither Anti-A and anti-B OO A.Kewan 9 Blood Antigens Antibodies Can give Can Group blood to receive blood from AB A and B None AB AB, A, B, O A A B A and AB A and O B B A B and AB B and O O None A and B AB, A, B, O O A.Kewan 10 Average Percents… A.Kewan 11  The Rhesus (Rh) System  Landsteiner and Weiner in 1940 discovered other antigens in human R.B.Cs and named rhesus antigens or Rh-antigen(D-antigen) because the same antigens are present in monkey.  One of the basic difference between ABO and Rh systems is that the Rh antibodies are not natural i.e. they are not present at birth but are synthesised in Rh negative persons in response to the presence of Rh- antigen. A.Kewan 12 Rh Factor If your blood does contain the Rh protein, your blood is said to be Rh positive (Rh+) If your blood does NOT contain the Rh protein, your blood is said to be Rh negaitive (Rh-) A.Kewan 13  Rh System  Antibodies to rhesus factor only develop in two circumstances: 1. transfusion of Rh +ve cells to Rh –ve person 2. The presence of Rh +ve fetus in Rh –ve mother A.Kewan 14 A.Kewan 15  If you are You can donate to You can receive from group O A , B , AB , O O A A , AB O ,A B B , AB O,B AB AB A , B , O , AB RH status RH + RH + RH + , RH - RH - RH + , RH - RH - A.Kewan 16 Blood transfusions – who can receive blood from whom? People with blood group O are called "universal donors" and people with blood group AB are called "universal receivers." A.Kewan 17  Principle  The test procedure based upon the agglutination (clumping) of RBCs which carries a specific antigen in the presence of a corresponding specific Antibodies A.Kewan 18 Agglutination A.Kewan 19 Materials 1. Blood group sera ( Anti-A, Anti-B, Anti-D). 2. Disposable blood group slides. 3. Lancets. 4. Alcohol swap. 5. Viewing box. 6. Glass rod. 7. Microscope. A.Kewan 20  Method 1. Obtain a drop of blood from a finger prick in each of the circles of the disposable blood group slides. 2. Add one drop of Anti A ( blue ) and a drop of Anti B (yellow ) and a drop of Anti D sera in the proper circles on the disposable blood group slide. 3. Using clean (uncontaminated ) glass rod to mix the blood with antiserum. 4. Tilt the slide from side to side occasionally, and after 2 minute read macroscopically for agglutination. A.Kewan 21 5. Any apparently negative tests should be read microscopically after 5 minute. Report the result as follow :  Agglutination ( clumping ) take place in the circle which has Anti A , but not with that of Anti B ,then blood group for this sample is A. A.Kewan 22  Agglutination ( clumping ) take place in the circle which has Anti B , but not with that of Anti A ,then blood group for this sample is B.  Agglutination ( clumping ) take place in the circle which has Anti A and Anti B , then blood group for this sample is AB.  No agglutination take place in both Anti A and Anti B circles, then the blood group for this sample is O A.Kewan 23  For RH if agglutination ( clumping ) take place in the Anti D circle , then this mean RH positive while if not it means RH negative. A.Kewan 24   O – pos.  O – neg.  A – pos.  A – neg.  B – pos.  B – neg.  AB – pos.  AB – neg. A.Kewan 25 Results A.Kewan 26