Immunoenzyme analysis: application and features of the

Immunoenzyme analysis is a laboratory study based on the detection of "antigen-antibody" complexes by means of a special enzymatic label, which is revealed through a change in the color of the substrate. The main purpose of this analysis is to determine the availability of various products of enzymatic reactions in test samples.

To identify antigens and antibodies, a heterogeneous enzyme-linked immunosorbent assay is used, since in its process it is easy to separate the components of the reaction and to trap some of them in the solid phase.

It is worth noting the following advantages of this laboratory study:

• high sensitivity, which makes it possible to detect even a small number of molecules of the corresponding substances;

• for this analysis, a minimum number of test materials can be used;

• the ability to store all components that are necessary for analysis for a long time;

• Ease of implementation;

• availability of instrumental and visual results;

• the enzyme immunoassay is automated at each stage of the reaction;

• The relatively low cost of the sets that are used for diagnosis.

These advantages make it possible to widely use ELISA in various fields of medicine, including, for the diagnosis of viruses.

The most common technique for immobilizing antibodies and antigens is the adsorption reaction, when individual molecules attach to the solid phase (due to ionic or hydrophobic interactions or due to the formation of a hydrogen bond).

I must say that the enzyme immunoassay is used in two cases:

• for detection of antigens of pathogens of various infections;

• to determine the presence of antibodies to the antigen of pathological microorganisms (it should be noted that with the help of ELISA, almost any sexual infection can be detected).

To conduct this serodiagnostics, use a special polystyrene plate. It has 96 holes, on the side surfaces of which the antigen is adsorbed. When the serum is injected into the cells of the plate, appropriate antibodies are attached to the antigen. With a subsequent addition of labeled antibodies to human immunoglobulins , a specific reaction passes through the wells. The next treatment of the serum with the chromogen (dye) changes the color of the substrate (in the presence of the corresponding "antigen-antibody" complexes). It should be noted that the intensity of the color is directly proportional to the number of antibodies.

The ELISA analysis ends with measuring the optical density of the liquid in the cells of the plate. At the same time they use special devices and sample samples, which help count the concentration of antibodies. It should be remembered that each test system for carrying out this analysis has its own values of normative indicators (this, as a rule, is prescribed in the results that are given out on hands).

With the help of ELISA, syphilis, viral hepatitis and HIV infection are diagnosed, and also cytomegalovirus, chlamydia, and herpes (of various types) are found in the human body. This analysis also helps to determine the level of hormones, to identify cancer markers.

Where to take tests in Moscow? To date, there are many specialized laboratories that offer a wide variety of serological studies. To obtain a referral, you should consult a local health center doctor (or a private specialist, to whom you are going). With the test results, you should also go to the doctor. And listen to his comment about the need for any treatment.