Blood typing/grouping
Apparatus and reagents
- Antisera A, B, and D
- Lancet
- Clean grease-free glass slides
- Microscope
- Slide warmer
- Dropper
- Normal saline
- Toothpick
- Cotton swab
- Alcohol
Principle
The red cells contain different types of agglutinogens (antigens) and the plasma contains agglutinins (antibodies). In order to determine the blood group of a subject, the red cells are allowed to react with sera containing known agglutinins.Reaction
Agglutination results due to the reaction of agglutinogens with complementary antibodies or agglutinins.Agglutinogens + Agglutinins => Agglutination
A + Antibodies A => Agglutination
B + Antibodies B => Agglutination
Universal donor
A person with type O type i.e., B agglutinin but no agglutinogensUniversal recipients
A person with type AB i.e., A and B agglutinogens but no agglutinin.Procedure
- Obtain a clean microscope slide and divide the glass slide into three equal parts with a glass marking pencil.
- Mark one end A, the other end B, and in the center D.
- Pre-warm the slide by placing it on a slide warming box.
- Lance the fingertip to obtain a good-sized blood drop.
- Place one drop of blood on each end of the marked slide and two drops in the center of the slide.
- Add 1 drop of anti-A serum to the A-side.
- Add 1 drop of anti-B serum to the B side.
- Add 1 drop of anti-d serum to the center of the slide marked as D.
- Mix the antiserum and blood with a toothpick.
- Spread each mixture over the slide slightly.
- Observe the slide for any agglutination of red cells by holding the slide from one end and tilting/rotating it in all directions by avoiding the mixing of the two sera.
- Inspect the sera first with the naked eye to see whether any clumping and agglutination have taken place or not. Confirm under the microscope.
Comments
Post a Comment