Enzymatic immunoassay is a laboratory study based on the detection of antigen-antibody complexes using a special enzymatic label, which is detected due to a change in the color of the substrate. The main purpose of this analysis is to determine the presence of various products of enzymatic reactions in test samples.
To detect antigens and antibodies, a heterogeneous enzyme immunoassay is used, since in its process it is easy to separate the reaction components and hold individual 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 amount of molecules of the relevant substances;
• The minimum amount of test material can be used for this analysis;
• the ability to save all the components that are necessary for analysis for a long time;
• ease of implementation;
• availability of instrumental and visual results;
• enzyme immunoassay is automated at each stage of the reaction;
• relatively lowthe cost of kits that are used for diagnostics.
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 are attached to the solid phase (due to ionic or hydrophobic interactions or due to the formation of a hydrogen bond).
I must say that enzyme immunoassay is used in two cases:
• to detect antigens of pathogens of various infections;
• to determine the presence of antibodies to the antigen of pathological microorganisms (it is worth noting that almost any sexual infection can be detected using ELISA).
To conduct this serodiagnosis, a special polystyrene plate is used. It has 96 wells, on the side surfaces of which the antigen is adsorbed. When the test serum is introduced into the cells of the tablet, the corresponding antibodies are attached to the antigen. When the labeled antibody to human immunoglobulins is subsequently added to the wells, a specific reaction occurs. During the next treatment of the serum with a chromogen (dye), the color of the substrate changes (in the presence of the appropriate antigen-antibody complexes). It is worth noting that the color intensity is directly proportional to the amount of antibodies.
The ELISA analysis ends with the measurement of the optical density of the liquid in the wells of the tablet. Whereinuse special devices and templates that help calculate the concentration of antibodies. It should be remembered that each test system for conducting this analysis has its own values of normative indicators (this is usually prescribed in the results that are handed out).
With the help of ELISA, syphilis, viral hepatitis and HIV infection are diagnosed, and cytomegalovirus, chlamydia, herpes (of various types) are detected in the human body. This analysis also helps to determine the level of hormones, to identify cancer markers.
Where to get tested in Moscow? To date, there are many specialized laboratories that offer a wide range of serological tests. For a referral, you should consult with your local he alth care provider (or a private specialist you trust). With the results of the tests, it is also worth going to the doctor. And listen to his comment regarding the need for any treatment.
