AIM: To determine the ABO blood group and Rh typing of the given blood sample.
INTRODUCTION:
Immunohaematology
is an application of the principles of immunology to the study of red cell
antigens and their corresponding antibodies in blood. Karl Landsteiner in
1900 discovered the fundamental principles of blood grouping. He discovered
ABO-blood group system in human beings.
All
people of ABO system can be divided into 4 major groups. They are “A” group,
“AB” group, “B” group and “O” group.
This
depends on the presence of antigen on the RBCs. A person with blood group
"A" will have antigen "A" and person with blood
group"B" will have antigen "B" and with “O” group neither
“A” or “B” antigen.
Rh
Typing:
Rhesus
(Rh) blood group system is clinically the second most important blood group system
in humans after ABO blood group system. It was discovered in 1940 by
Landsteiner &Wiener. Rh antibodies are not naturally occurring but develop
only after exposure to Rh antigen.These are of IgG type.
PRINCIPLE:
To
detect the group an antiserum having a high concentration of antibodies against
this pecific antigen is employed. This antiserum when mixed with whole blood
shows agglutination if the RBCs possess the specific antigen in its surface
e.g. antiserum A will show agglutination with RBCs having A antigen and hence
persons blood group will be indicated as "A".
People with „B‟ antigen on their cells have anti-A in their
serum, those of group O have both anti-A and anti-B and those of group AB have
neither antibody. These facts are known as „Landsteiner‟s rule‟
REQUIREMENTS:
1.
Glass slides
2.
Match sticks
4.
Anti-A, Anti-B and Anti-D Monoclonal agglutinating antisera.
PROCEDURE:
(1) Sterilize
the tip of your middle fmger with sterilized cotton wet in 90% alcohol.
(2) Let the tip
of the finger become dry. (3) Prick the finger with a sterilized needle.
(4) Collect the blood in sample vial
containing 1 ml of 0.85% sodium chloride (0.85 gms of sodium chloride powder
dissolved in 100 cc. of distilled water.
(5) Take 2 cavity
slides, each with 4 cavities wash and clean them and let the slide become dry.
(6) Label the
cavities of the slides no. 1 and no. 2. such I, II, III and IV in no. 1 slide
and V, VI, VII and VIII in no. 2 slide.
(7) Add a drop of 4, different samples
of blood in each cavity
as under
Cavities I V - First sample of blood
Cavities II VI - Second sample of blood"
Cavities III VIII - Third sample of blood
Cavities IV VIII - Fourth sample of blood
- Mix well with a pricking stick individually and observe for agglutination after a few seconds/ minute.
- Blood group is indicated as agglutination of RBCs with specific antisera.
- Agglutination of the patient is as shown in figure.
- 1. If
the corpuscles contain A, the serum contains β, the blood group is A.
- 2. If
the corpuscles contain B, the serum contains A the blood group is B.
- 3. If
the corpuscles contain both A and B, the serum is free from α and β, the blood
group is AB (universal receiver).
- 4. If
the corpuscles contain neither A nor B,
the serum contains both α and β, the blood group is O (universal donor).
- a. Agglutination by α but not by β= Croup A
- b. Agglutination by β not by α = Group B
- c. Agglutination by both α and β = Group AB
- d. No agglutination by α and β = Group O.
RESULT:
The
ABO blood group of the given sample is _____________.
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