Blood grouping is the determination of the presence or absence of ABO and RH1(D) antigens.
Blood group determination is carried out in 2 stages:
Forward typing
Where the presence of antigens on the surface of Red Blood Cells (RBC) is investigated with known antisera
Reverse typing
Where the presence of anti-ABO antibodies in the plasma is investigated with known antigens (commercial RBC)
The agreement between the results of the direct test and that of the retest is a sine qua non condition for the determination of a blood group to be validated.
DIAGAST produces monoclonal antibodies and red blood cells for the direct and counter-assay, respectively.