Is it true that it is safe to vaccinate with existing antibodies after a disease?

Many are concerned about whether it is necessary and safely vaccinated if a certain titer of antibodies is preserved against a previous coronaviral infection. We decided to find out what doctors and immunologists say about this, and figure out whether vaccination is necessary in this case.

One of arguments People against compulsory vaccination are that people who have antibodies after illness are sent to vaccine. Numerous statements various speakers about the possibility of an antibody -dependent increase in infection, as well as insufficient awareness of the functioning of immunity. Some resources are straight write On the danger of vaccination with antibodies available from illness.

Position WHO, Russian politicians And doctors The same: they unanimously repeat that vaccination is necessary six months after recovery, regardless of the level of antibodies. At the same time, in these publications it is difficult to meet something other than an unproven statement that protection is not enough.

To understand why vaccination is needed with existing antibodies after an illness, it is necessary to understand the mechanisms of a specific immune response. When pathogen enters the body develop Two types of answer at once: cellular and humoral. The cellular immune response is realized in the form of activation of the cells of the immune system, primarily its T-cell link, and humoral-the occurrence of antibodies in the blood plasma. 

Antibodies, or Immunoglobulins, - these are large globular proteins of blood plasma, necessary to neutralize various pathogens (mushrooms, bacteria, parasites, viruses). Five antibodies are represented in the human body: Iga, IgG, IGD, Ige and IgM. Each class has its own tasks, but in the context of the disease, the most important are immunoglobulins M and G. The former characterize the acute course of the disease and are neutralized by the body with recovery, the latter serve as a marker of the transmitted disease and have a longest lifetime. In this text, it will be discussed precisely about vaccination in IGG class antibodies that arose after illness.

Each individual antibody capable To recognize the unique element of the pathogen is an antigen, or rather, even a separate area is an epitope.

Describing the principle of antibodies, many scientists They come running To the image "Key - Castle". The castle in this case are different sections of the pathogen that are captured and studied by “interceptors” cells-macrophages, the information is transmitted to the “factories” cells-B-lymphocytes, which, in turn, begin to produce various options for “keys”-antibodies to many different epitopes of coronavirus. Having defeated the infection, part of the B-lymphocytes become memory cells storing “recipes” of antibodies, in order to make a “key” according to the already worked out technology at a future meeting with the pathogen.

A logical question arises at this level: why then vaccination is needed, if the antibodies have been developed and the recipe has already been recorded? Let's try to figure it out. 

Firstly, the life span has antibodies different. For example, antibodies to measles have been preserved in the body all their lives, and to salmonelle, they disappear after 6-12 months. Antibodies to coronavirus persist at least three months, according to data Examination of 20,000 people. However, there is data as more long saving, and more short. Vaccination after illness stimulates The development of new antibodies. That is why recently Ministry of Health It also recommends revaccinated.

Secondly, not all antibodies have the same effectiveness to neutralize the virus. According to the latest data, the body on average produces 255 different types of antibodies, only 27 of which Show High efficiency to prevent the disease. Antibodies There are binding, they can only put on coronavirus, and neutralizing, that is, capable of preventing it from entering the cage. Therefore, a simple quantitative counting of antibodies will not give us information whether they will cope with the infection or not. Developers Created Vaccines with the most effective antibodies aimed at the most vulnerable and least prone to mutations of the epitopes of the virus-the RDB-domain of the S-chip. The test in the usual commercial laboratory does not give information whether the patient’s antibodies are able to effectively reflect the protection of the virus, because for this study it would be necessary to grow a cell culture, infect it with pseudo -Russian (coronavirus imitation) and then try to neutralize the subject of blood serum of the subject.

Thirdly, the body always functions in the mode of energy saving, therefore, faced with the already famous pathogen, it contrasts He previously prepared antibodies, and does not study the virus again. Coronavirus mutates fast enough, so the chance is great that the previous “key” to the new castle is no longer suitable, and the immunity will either not notice it or will react with a delay when the infectious process is already launched, which will cause a more severe disease. Moreover, the virus can use the antibody attached to it to penetrate the cells of the immune system and begin to multiply in it. Such a process is called an antibody -dependent increase in infection. It is possible with primary or secondary infection, as well as during vaccination with subsequent disease. However, the risk of its occurrence after vaccination Assessed As low so that they can simply neglect them. Today 3.13 billion people Received at least one dose of any vaccination, while not a single case of an antibody-dependent increase Fixed. Moreover, for the SARS-COV-2 virus not succeeded Get it even on any animal model.

Thus, vaccination six months after the disease, even with antibodies remaining in the body, is not only safe, but also with a high probability can protect the body from the subsequent disease and the severe course of the disease.

Is it true

What do our verdicts mean?

Read on the topic:

1. A new wave of an epidemic in Russia. Live broadcast with molecular biologist Olga Matveeva
2. Lecture by Alexei Vodovozov “Vaccines and Covid: Threats and Calls”
3. Covid-19: New explosion. Denis Protsenko about the third wave of the epidemic. Antonims with Anton Krasovsky