How to perform B ABO in blood grouping system.

How to perform B ABO in blood grouping system.

1. ABO Blood Group Testing OA AB B AB O A B

2. Objectives At the end of this module you will be able to: Identify the major human blood groups and their blood group antigens and antibodies Recognise characteristics of naturally occurring ABO antibodies Identify antigens and antibodies tested in ABO forward and reverse grouping tests

3. Primary ABO Blood Groups

4. ABO Blood Group System Karl Landsteiner

5. ABO Antigens "ABO blood group diagram" by InvictaHOG - Own work. Licensed under Public domain via Wikimedia Commons

6. ABO Antigens (Simplified) Group A Group B Group AB Group O A antigen B antigen

7. ABO Naturally Occurring Antibodies Landsteiner’s Law states; An antibody will not develop in the plasma of an individual unless the corresponding antigen is absent from their red cells. Individuals produce anti-A and/or anti-B in response to A and B antigen-like sensitising factors such bacteria and viruses in the environment.

8. ABO Antigens and Antibodies Blood Group Antigens on RBCs Antibodies in plasma A B AB O A B A and B None Anti-B Anti-A Anti-A, Anti-B and Anti-A,B None

9. ABO Testing Products Reagent antisera Diluent control Reagent RBCs All routine ABO blood group tests are performed using haemagglutination methodology at room temperature.

10. RBC Tests - Forward Group Anti-A and Anti-B reagents Monoclonal diluent control Tests on sample RBCs is called ‘forward grouping’ or ‘front typing’ as it directly tests for A and B antigens

11. Reagent A ntisera Reactions + (Positive) + (Positive) - (Negative) - (Negative)

12. Grades of Agglutination ABO blood group reactions can be graded as 0, 1+, 2+, 3+ or 4+. Mixed field reactions may also be observed. No agglutination = Negative (0) Any visible agglutination = Positive (+)

13. Plasma Tests - Reverse Group Reagent A 1 and B Red cells Tests on sample plasma is called ‘reverse grouping’ or ‘back typing’ as tests for naturally occurring anti-A and anti-B antibodies in the plasma – Antibodies that are the ‘reverse’ of the individual’s ABO RBC antigens.

14. Reagent RBC Reactions + (Positive) + (Positive) - (Negative) - (Negative)

15. Exercise 1: ABO Blood Group Testing Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells + - - + A Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells - + + - B Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells - - + + O

16. Exercise 2: ABO Blood Group Testing Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells + + - - AB Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells + - + + Forward group Reverse group Result Anti-A Anti-B A 1 cells B cells - + - - ?A 2 ?B

17. Immucor’s ABO poster

18. Wrap-Up and Discussion Now you should be able to: Identify the major human blood groups and their blood group antigens and antibodies Recognise characteristics of naturally occurring ABO antibodies Identify antigens and antibodies tested in ABO forward and reverse grouping tests

19. RhD, Weak D and Partial Ds

20. Objectives At the end of this module you will be able to: Identify the main antigens in the Rh Blood Group System Recall processes in RhD and Weak D testing Perform RhD and Weak D testing

21. Rh Blood Group System Antigens The five most important antigens in the Rh Blood Group System are; D C c E e Other Rh antigens include; C w G f Discovered approximately 60 years ago, there are now around 50 antigens in the Rh blood group system Two highly polymorphic genes RHD and RHCE code for all the Rh antigens

22. RhD Antigen Rh factor Rh positive Rh negative RhD positive (D antigen present) RhD negative (D antigen absent) Rhesus blood group system RhD is considered the most important blood group antigen after ABO due to it’s immunogenicity

23. RhD Antigen and Immune A nti-D Unlike ABO, individuals that lack the RhD antigen do not automatically produce anti-D Immune (or allo ) anti-D can be produced after a sensitising event Blood transfusion Pregnancy Organ transplantation

24. RhD Testing RhD status is determined by testing the RBCs (unknown antigen) with reagent Anti-D (known antibody) and antisera control to confirm any agglutinations observed is due to the reagent antibody only Anti-D reagents Monoclonal diluent control

25. RhD Assay Reactions + (Positive) - (Negative)

26. Grades of Agglutination RhD assay reactions can be graded as 0, 1+, 2+, 3+ or 4+. Mixed field reactions may also be observed. No agglutination = Negative (0) Any visible agglutination = Positive (+)