A person’s blood group is an inherited factor and is determined by the genotype of his parents. There are several blood group systems . The most popular is ABO, which is determined by the corresponding genes.
The determination of the blood group is necessary for any transfusions (erythrocyte mass and plasma), as well as for transplant operations. Any manipulations with the tissues of the human body require compliance with antigenic compliance, which is determined by the group according to the AB0 system.
Today, there are two main areas (methods) by which blood type determination is performed. Both of them are reliable and reliable. The first of these and the simplest is the determination of the blood group by the reaction of isohemagglutination. The second is the cross-sectional method (the agglutinogens are detected in the first way and the agglutinins are additionally determined using red blood cells). A variation of the first method is the determination of the blood group by cyclonic clones (in contrast to the standard serum method, cyclonic clones are not susceptible to HIV and hepatitis contamination).
Sample with isohemagglutinating serum
Such sera contain agglutinins (antibodies) for four groups, the activity of which is determined by the titer.
When mixing the patient’s blood serum with standard serums to determine the group, the appearance of agglutination is observed (a positive reaction is the bonding of red blood cells with subsequent flocculation, while the serum is discolored). A negative reaction is manifested by a uniform pink color without flocculation.
Interpretation of Results
If when setting the reaction 3 serums give a negative reaction, then - blood group O (I).
With positive O (I) and B (III) and negative A (II) - blood group A (II).
If the sera O (I) and A (II) are positive, and B (II) are negative, this is group B (III).
When all three serums give a positive reaction, blood group AB (IV). In this case, it is necessary to conduct an additional study with blood serum AB (IV) group. A negative agglutination reaction confirms the AB (IV) blood group.
Using cyclones, the blood group is determined in the same way. The main difference between cyclonic and standard sera is the complete absence of polyagglutination as a result of non-specific red blood cell reactions. Another special feature of cyclonic reactions for diagnosing groups according to AB0 is high avidity (that is, the visual severity of the agglutination reaction). Compared to standard sera, the avidity of the cyclones is much higher, which increases the reliability of the samples.
The technique for determining the blood group basically comes down to the formulation of specific agglutination reactions. On a tablet (or plate) in special wells, standard serums or coliclones are applied, then a few drops of the test blood are added to each of them. The reaction is detected within two to three minutes by shaking the plates (plates) with reagents. As already mentioned above, the large bright red flakes formed indicate a positive reaction, that is, the presence of antigens to standard serum antibodies for this blood group.
Thus, the determination of the blood group is a simple reaction and can be carried out in two main variations of the technique. The most complex of them are the most informative and reliable. The significance of a correctly identified blood group is very high, as it should be taken into account during various transfusions and transplantations. That is why, before any operation, samples are taken to determine the patient's blood group.