In the Middle Ages, repeated attempts were made to transfuse blood from animals to man and from man to man. However, almost all of them ended tragically. The first successful transfusion of human blood to the victim was made in 1667 by doctor Denis. The causes of severe complications arising from blood transfusions were first established in 1901 by Karl Landsteiner. He mixed drops of blood of various people and found that in some cases erythrocyte sticking occurs - agglutination and their subsequent hemolysis. On the basis of his experiments, Landsteiner concluded that there are proteins agglutinogens in erythrocytes that contribute to their gluing. He identified 2 agglutinogens A and B. Based on their absence or presence in red blood cells, he divided the blood into groups I, II and III. In 1903, his pupil Adriano Sturli discovered blood group IV. Later, proteins were found in the blood plasma that interact with agglutinogens and cause adhesion of red blood cells. They were called agglutinins a and b. It is now established that erythrocyte membrane glycoprotein, glycophorin, has antigenic properties. Agglutinins are immunoglobulins M and G, i.e. g-globulins. Agglutinogen A and agglutinin a, as well as agglutinogen B and agglutinin b are called the same. When they interact, erythrocyte glueing occurs. Therefore, only dissimilar agglutinogens and agglutinins are found in human blood. In the blood of newborn agglutinins no. However, then food components, substances produced by intestinal microflora, contribute to the synthesis of agglutinins that are not present in the erythrocytes of a given person.

Blood groups of the ABO system are denoted by Roman numerals and the duplicate name of the antigen:

I (0) - there are no agglutinogens in erythrocytes, but plasma contains agglutinins a and b.

II (A) - agglutinogens A and agglutinins b.

III (B) - agglutinogens B and agglutinins a.

IV (AB) - in erythrocytes agglutinogens A and B, plasma agglutinins are absent.

At present, it has been found that there is a weak H-antigen in the erythrocytes of group I. Agglutinogens A are divided into subtypes A1 and A2. The first subtype is found in 80% of people and has more pronounced antigenic properties. Transfusion reactions between the blood of these subgroups do not occur.

Inheritance of the blood group is carried out by the genes A, B and O. In the human chromosomes there are 2 of them. Genes A and B are dominant. Therefore, for parents with blood groups II and III, the child can have any of the 4 groups.

3.OA + OB = VO

In 1940, K. Landsteiner and I. Wiener discovered another agglutinogen in erythrocytes. It was first found in the blood of rhesus monkeys. Therefore, they were called Rh factor.

Currently, only one-group blood transfusion through the ABO system is allowed. To determine the group affiliation, a drop of test blood is mixed on a slide with a drop of standard sera of groups I, II and III. This method determines the antigenic properties of red blood cells. If no agglutination has occurred in any of the sera, therefore there are no agglutinogens in the erythrocytes. This is the blood of the first group. When agglutination is observed with sera of groups I and III, then the erythrocytes of the test blood contain agglutinogen A. That is, This is the blood of group II. Agglutination of erythrocytes with sera of groups I and II indicates that they contain agglutinogen B and this blood of group III. If there is agglutination in all sera, then the erythrocytes contain both antigens A and B. Ie blood IV group. It is advisable to conduct a study with serum IV group. More precisely, the blood group can be determined using standard red blood cells of groups I, II, III and IV. To do this, they are mixed with the serum of the test blood and determine the content of agglutinins in it. Rhesus blood affiliation is determined by mixing it with serum containing rhesus agglutinins.

In addition, to avoid mistakes in determining blood type and

the presence of D-antigen, apply a direct test. It is also necessary to detect blood incompatibility due to other antigenic signs. A direct test is made by mixing the donor's erythrocytes with the serum of the recipient at 37 ° C. With negative results, the first portions of the blood are poured fractionally.

Algorithm of actions in determining the blood group and Rh factor
when a woman enters a maternity hospital

Blood group determination of the AB0 system with monoclonal antibodies

Prepare:

• dry glass (plate type) for determining blood type;
• anti-A cyclones ( pink colour) and anti-B (blue);
• two pipettes for collecting the cyclones from the vials;
• two glass sticks for mixing the patient's blood with the cyclones;
• a disposable syringe (5-10 ml) with a needle to draw blood from the patient's vein;
• in a sterile tray put 3 balls moistened with alcohol, 2-3 sterile wipes;
• rubber band for intravenous puncture;
• dry centrifuge tube, on which the glass detector clearly sign the patient's name;
• a blank is a referral to a laboratory where a blood type, RH affiliation is redetermined by a laboratory doctor, the seal is stamped and signed

Observing all the rules for intravenous punctures, make blood from the patient's vein (at least 5 ml).

• Anti-A and Anti-B polyclones are applied to the plate or plate in one large drop (0.1) under the appropriate inscriptions: anti-A and anti-B.
• Next to the drops of antibodies, the test blood is applied in one small drop (0.01 ml).
• After mixing the reagents and blood with different glass rods for anti-A and anti-B in a ratio of 1:10, the agglutination reaction is observed for 2.5 minutes.
• Reading results after 5 minutes while stirring the drops. (from 3 to 5 minutes)
• The result is evaluated by a doctor. Evaluation of the results of the agglutination reaction with anti-A and anti-B Coliclones is presented in the table, which also includes the results of the determination of serum agglutinins (plasma) of donors using standard red blood cells.

In order to exclude auto-agglutination, which can be observed in umbilical cord blood of newborns, in the case of establishing the AB (IV) blood group, it is necessary to conduct a control study: mix one drop (0.1 ml) of an isotonic sodium chloride solution with a small drop (0.01 ml) of the test blood. Agglutination reaction should be ABSENT.

BUT.Carefully fill in all the columns of the form - referral to the laboratory to determine blood type and RH affiliation with the signature of the doctor.

AT.   Deliver a blank referral and a test tube with the patient's blood to the laboratory for careful determination of the blood type and rhesus of the patient.

Determination of Rh factor using monoclonal reagent (Zoliklon anti-D Super)

A large drop of reagent (about 0.1 ml) is applied to the plate. A small drop (0.01-0.05 ml) of the test blood is placed next to it and the blood is mixed with the reagent. The agglutination reaction begins to develop after 10-15 seconds, a pronounced agglutination occurs after 30-60 seconds. (Rh positive, no agglutination - Rh negative). The results of the reaction take into account after 3 minutes.

After mixing the reagent with blood, it is recommended that the plate should not be shaken immediately, but after 20-30 seconds, which allows developing more complete large-petal agglutination during this time.

Express determination of ABO and rhesus blood groups using the Erythrotest-GruppoCard kit

The Eritrotest-Group Card (Hematologist LLC, Moscow) set is designed to determine ABO and Rhesus (RhD) of human blood groups in laboratory and field conditions. The determination is carried out in the direct hemagglutination reaction and does not require any auxiliary reagents and equipment. The kit includes:

• eritrotest-Groupcard card;
• a pipette with a dosed drop volume of about 0.02 ml;
• sterile packaged scarifier;
• stick for mixing blood with reagent.

In the wells of the card are dried monoclonal anti-A, anti-B, anti-AB and anti-D reagents, which immediately dissolve when water is added. Monoclonal anti-D antibodies specifically detect the RhD antigen independently of the ABO group. In the last well is the solvent for the production of controls on non-specific autoagglutination.

The course of determination:

The determination is made in native blood with a preservative, in blood without a preservative, or blood taken from a finger.

• Open the package and take out the card, without touching the holes with the working surface. Enter the patient's data, except for blood type.
• 1 drop of water (tap or distilled) is added to each well using a pipette attached to the kit. Water is applied to the stain of dried reagent. Do not allow drops to dry.
• A small drop of test blood is introduced into each well. Blood is applied next to a drop of reagent, without touching it to avoid contamination of one reagent with another. To take blood from a finger, use a sterile scarifier.
• Thoroughly mix the blood with the reagent with the help of the stick inserted into the kit. In each well, mixing is done only with a new stick. The use of a single stick for mixing in different wells is not permissible, since it leads to contamination of the reagents and an erroneous determination of the blood group.
• Immediately shake the plate. A clear agglutination occurs in 10-30 seconds, but the final result should be considered after 3 minutes, because in the case of weak forms of antigen A, the reaction occurs later, and the agglutinates are smaller.
• The result is evaluated visually (table. 18.6). Enter the result of the reaction with the appropriate reagent (+ or -) in the squares under each well.

  Table 18.6. The results of the reaction in the set of "Erythrotest-Grupokart" and blood type
  Anti-A	Anti-B	Anti-AV	Anti-O	Blood type
  -	-	-	-	0 (I) Rh - neg.
  -	-	-	+	0 (I) Rh - pos.
  +	-	+	-	A (II) Rh - neg.
  +	-	+	+	A (II) Rh - pos.
  -	+	+	-	In (III) Rh - neg.
  -	+	+	+	In (III) Rh - pos.
  +	+	+	-	AB (IV) Rh - Neg.
  +	+	+	+	AB (IV) Rh - pos.

• Enter the blood group. The conclusion about blood type can be made only in case of absence of reaction in the control (last well).
• Cut off the line with the hole with blood, and save the card.

The shelf life of the Eritrotest-GroupCard set is 2 years at a temperature of 2-8 ° C. Storage is allowed for 1 year without a refrigerator if the temperature does not exceed 25 ° C. Storage and use of unsealed or damaged packages is not allowed.