In different people, the blood composition is about the same, it includes similar basic elements. True, there are eight types of blood, determined by the presence or absence of specific antigens. These components can cause reactions of the immune system in the event that they are foreign to it. Blood is divided into four groups according to its type of antigens, and, in addition, into two large categories according to the Rhesus factor.
Let's consider this question in more detail.
How were blood types discovered?
Experiments aimed at transfusion of blood and its components have been carried out for hundreds of years. To some, such treatment saved their lives, however, most people, after transfusion, unfortunately, died. The causes of this phenomenon remained unknown until 1901, until the Austrian doctor K. Landsteiner discovered the difference between the blood samples of patients.
So in the process of experiments, the doctor noted that in some situations, mixing the blood types of two patients could lead to agglutination, that is, to the process of red blood cell adhesion. Then it turned out that just such a process leads to fatal consequences. As it turned out, the incompatibility of different people is caused by an immune response.
In the event that the recipient has antibodies directed against donated blood, then the immune system tries to get rid of such foreign cells. Landsteiner's work made it possible to distinguish four groups of biomaterial and make transfusion safe. For this discovery, the scientist was awarded the Nobel Prize. Next, we will go on to consider the types of blood groups and find out how much of them are allocated in medicine.
Classification
The difference between blood in humans is primarily in the presence or in the absence of a specific protein molecule called an antigen. Such a molecule is located on the surface of the red body of the red blood cell and in serum. It is these proteins that are responsible for the reaction of the immune system to someone else's biological fluid.
In different patients, combinations of such molecules may vary. They directly depend on the genetic information that a person has inherited from his parents. The group of this biomaterial is determined by the presence or absence of antigens “A” and “B” on the surface of an erythrocyte and antibodies to them in plasma.
In Russia, it is customary to call groups by numbers, namely, there is a second, first, third and fourth. International practice designates blood types in vessels according to the AB0 system, where 0 is the first group, A is the second, B is the third, and AB is the fourth:
- The first blood group has antibodies only in plasma.
- The second one has the antigen “A” on the surface of the red blood cell, and, in addition, the antibody “B” in the blood plasma.
- The third group has antigen “A” in the blood plasma and “B” on the surface of the red blood cell.
- The fourth group has antigens "A" and "B" directly on the surface of the red blood cell.
It is important to find out in advance what type of patient's blood is.
Now consider what the Rhesus factor is.
How do rhesus factors differ?
In addition to antigens “A” and “B”, the Rh factor also exists on the surface of the red blood cell in patients. This is also the kind of antigen that eighty-five percent of Europeans have. It is also noted in ninety-nine percent of Asians. Such people are called Rh-positive, they are indicated by the indicator "RH +". Those who do not have a Rhesus factor in their blood are called Rh-negative patients with an RH- value.
In the event that blood is transfused from one person with a negative "RH-" to a patient with a positive, then problems usually do not arise. In the opposite situation, Rhesus antibodies can begin to be produced in the blood of the recipient, leading to the destruction of red blood cells. Given the presence of the Rh factor, in total there are as many as eight blood groups in medicine.
What happens if you mix the blood of various groups?
In the event that the blood types of the recipient and the donor are incompatible, agglutination occurs in the form of adhesion of red blood cells against the background of antigen interaction processes. A similar process occurs if, for example, a person with group "B" receives the blood of a patient with type "A".
Agglutinated red blood cells clog blood vessels and stop the circulation of biological fluid. Such a process may resemble the formation of blood clots, however, it is caused by several other reasons. In addition, broken red blood cells lose hemoglobin, which, being outside the cell, acquires toxicity. This can lead to fatal consequences.
Compatibility of various blood groups
Despite the difference in the content of antigens, in a number of certain cases transfusion from a donor to recipients with different groups is possible. Transfusion will be safe only if the recipient does not have antibodies to the donor antigens. So, patients with a blood group of “0 Rh-” are considered universal donors, because they do not have antigens and a Rh factor on the surface of an erythrocyte. People with the AB Rh + group are universal recipients, because there is no antibody to the antigen in the plasma of their biomaterial and there is a Rh factor.
It is also worth saying that the blood in different people is approximately the same in composition, although it can vary in the content of certain antibodies. This makes it possible to divide it into as many as eight groups. The ideal donor is a person with the same group as the recipient, and the Rh factor.
Next, consider blood cells and their types.
Blood cell types
The blood contains many types of cells that perform completely different functions, ranging from oxygen transport to antibody production processes. It is worth noting that some of these cells function only within the circulatory system, while the rest use it only for transportation, and perform their functions in completely different places.
What kind of cells are they?
Blood cells: white blood cells and red blood cells
Blood cells are divided in medicine into red and white elements (i.e., white blood cells and red blood cells). The latter remain in the blood vessels, carrying oxygen with carbon dioxide. In addition, they are directly related to hemoglobin. Red blood cells are the bulk of the cells that circulate in the blood, are densely filled with hemoglobin and do not include any cellular organelles. White blood cells, as a rule, fight various infections, digesting the remains of destroyed blood elements. To do this, they pass through the walls of small blood vessels into the tissue. Now let's talk about the types of blood tests that are performed as part of the diagnosis when a patient is suspected of having a specific disease.
Types of Blood Tests
In medicine, there are the following types of tests, which, if necessary, are prescribed to patients:
- Clinical or biochemical analysis.
- Conducting a study on the concentration of glucose.
- Perform immunological analysis.
- Study of the hormonal profile and coagulogram.
- Performing an analysis to determine tumor markers.
- Performing a polymerase chain reaction.
Blood tests not only help to establish the presence of the disease, but also help to monitor the result of therapy. Biological fluid studies are very important for the diagnosis of various diseases. It is in connection with this that many people are interested in the question of what kind of blood tests are. In fact, there are a considerable number of them, and absolutely all of them are prescribed by the doctor, depending on the specific cases of pathology.
For example, the blood from the capillaries in the framework of the general analysis is obtained by piercing the phalanx of the finger on the hand with a special disposable sterile pen. To perform biochemistry, vein biomaterial is used. In addition, there are other laboratory tests that are conducted to determine sugar, hormones, tumor markers and other types of tests.
We examined human blood types, cells, and types of biological fluid tests.