ABO Typing

Interpretation of ABO Group

We can use the forward type together with the reverse type to interpret the ABO group. The expected reaction are as follows:

Red Cells Tested With Known Antisera

Serum Tested With Known Red Cells

Interpretation of ABO Group

Anti-A

Anti-B

Anti-A,B

A1 Cells

B Cells

4+

0

4+

0

4+

A

0

4+

4+

4+

0

B

0

0

0

4+

4+

O

4+

4+

4+

0

0

AB
+ = agglutination (graded 1+ to 4+)
0 = no agglutination or hemolysis

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