II. With anti A and anti B monoclonal antibodies, or anti A and anti B celiclones

Anti A and anti B celiclones are used for ABO blood grouping as an alternative to the standard isohaemaglutination serum by way of detecting antigens A and B in the red blood cells by the antibodies contained in celiclones. «Celiclone» is a diluted ascitic fluid of mice carriers of hybridomas that are producing of IgM against antigens A or B. As distinct from the standard ABO-serum, a celiclone provides a quicker and more pronounced reaction of agglutination. The use of celiclone eliminates the risk of transmission of hepatitis B or C viruses or HIV.

The grouping should be performed at 15-25 °C.

Procedure

• Place big drops of anti-A and anti-B celiclones on a labelled plate or a flat plastic surface.

• Put the drops of blood in question (which should be one-tenth as big in size nearby and mix using different sticks or different edges of the ground slide for each group).

• Shake the plate slightly and observe for about 2, 5 minutes (the reaction normally occurs within 3-5 seconds to form small red aggregates followed by flakes).

The following patterns of the reaction are possible:

1. Negative agglutination with both anti A and anti B celiclones suggests that blood contains neither A- nor B-agglutinogens and thus the patient's blood is of group I (0) (fig. 34, colour inset).

2. Positive agglutination with anti A celiclones indicative of A agglutinogens contained in the patient's red blood cells. The blood is therefore of group II (A).

3. Positive agglutination with anti B celiclones. The red cells of the blood under examination contain B agglutinogens and are consequently of group III (B).

4. Positive agglutination with both anti A and anti B celiclones. The patient's red blood cells contain A and B agglutinogens, which is suggestive of group IV (AB) blood (tab. 2).

Table 2. Agglutination reaction of tested red blood with celiclones anti-A and anti-B

Agglutination reaction		Tested blood group
celiclone anti-A	celiclone anti-B
-	-	I (0)
+	-	II (A)
-	+	III (B)
+	+	IV (AB)

If the reaction is positive with both anti A and anti B celiclones, i.e. the blood is supposed to be of group IV (AB), a further test should be performed using normal saline, to eliminate the possibility of non-specific agglutination. A big drop (0, 1 ml) of normal saline is mixed with a smaller one (0, 001 ml) of the test blood. The absence of agglutination supports the conclusion that the blood is of group IV (AB).

Liquid anti A and anti B celiclones are stored in ampoules or vials, labelled red for anti A and blue for anti B celiclones. They are to be kept in the refrigerator at 2-8 °C for two years.

Otherwise, agglutinative grouping is performed by using washed standard red blood cells.

III. With the standard washed red blood cells of the known group

Procedure. Place three to four millilitres of the patient's venous blood into a glass tube and centrifuge it. Put a few drops of the serum on a labelled plate accordingly and add a few drops of the standard red blood cells, one-fifth as big as those of the serum under investigation, mix these using the edges of a slide, and shake the plate for 3 minutes. Then mix one drop of normal saline with each portion and keep shaking the plate for some more time. Observe the reaction after 5 minutes. The four patterns of the reactions are possible:

1. A negative reaction with group I (0) red blood cells but a positive one with those of groups II (A) and III (B) imply the patient's blood being of group l (0).

2. A negative reaction with group I (0) and II (A) red blood cells but a positive one with those of group III (B) are indicative of the test blood being of group II (A).

3. A negative reaction with group I (0) and III (B) red blood cells but a positive one with those of group II (A) suggests that the blood under investigation is of group III (B).

4. A negative reaction with group I (0), II (A) and III (B) red blood cells signifies group IV (AB) blood.

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