PRINCIPLE AND TECHNIQUE IN ABO

Principle
Reverse grouping indicates the presence or absences of anti-A and anti-B in serum.

Techniques & procedures

Slide technique

Tube technique

  1. Add two drops of serum to be tested in each tube.
  1. Add one drop each of A and B cells suspension to the corresponding test tubes.
  1. Mix well and centrifuge both tubes at 1000 rpm for 1 minute.
  1. Gently remove the tubes and completely resuspend cells and examine macroscopically for agglutination and if negative, microscopically.
  1. Record the reactions and interpret the results
  1. Add a drop of serum to be tested on both sides.
  1. Using a clean applicator stick, mix the serum and cell suspension on both sides separately and spread into a smooth round circle.
  1. Add a drop of serum to be tested on both sides.
  1. Rock the slide gently for 2 minutes and look for agglutination.
  1. Mark a clean slide into two halves, labeling the left and right side side as A and B.

6.Record the reactions and interpret the results.

Principle

FORWARD

principle:
The forward grouping is the presence or absence of A and B antigens in RBCs.

Techniques & procedures

slide technique

  1. Place a tiny drop of well-mixed blood, either capillary or venous, on each slide.
  1. Using an applicator stick, combine one drop of blood with the anti-A.
  1. Using a clean applicator, repeat the procedure with anti-B and the other drop of blood.
  1. The slide is gently bounced for two minutes before being examined for agglutination under adequate lighting. Agglutination is a positive response that causes red blood cells to cluster together.
  1. Positive (+) or negative (-) outcomes should be reported (0).

tube technique

  1. Add eighteen to nineteen drops of saline to one drop of the patient's blood to make a 2-5 percent red blood cell suspension.
  1. Set up two tubes, one labelled "A" and the other "B," with one drop of anti-a serum in the "A" tube and one drop of anti-B serum in the "B" tube.
  1. Add one drop of the patient's 2-5 percent cell suspension to each tube and mix thoroughly.
  1. To speed up the process, the tubes are centrifuged for thirty seconds. After then, the tubes are removed from the centrifuge.

The presence or absence of the A, B and D antigen on human red blood cells can be determined by testing the red blood cells with the respective antisera, specifically Anti-A, Anti-B, Anti-AB and Anti-D. It is based on the principle of agglutination.

  1. ABO slide grouping is done with a commercial typing slide or a clean microscope slide divided into two half with a wax pencil.
  1. Apply one drop of commercial anti-A serum to the left side and one drop of commercial anti-B serum to the right.

REVERSE

  1. Label two test tubes as A and B.

NAME& ID:
1] ABIGAIL PRIYANKA THOMAS [012020090673]
2] ROSHINI A/P R ASOGAN [012020091620]