Immunity: how the immune system works, methods of strengthening and stimulating

Content:

Symptoms and Causes
Methods for strengthening immunity

One child constantly goes to kindergarten or school, without encountering any illnesses, and the other does not "climb" out of snot, pharyngitis and other "delights" of ARVI. There will also be at least one employee in the work collective who will “pull the entire department on himself” while the rest have the flu at home. Why is this happening? Now even a person who is far from medicine knows perfectly well what kind of resistance (resistance) the body is to infections, as well as the course of such diseases, depends only on how well "works" immunity.

However, the mechanisms of regulation of protection against pathogens, inhibition of the growth of opportunistic flora, which in a certain concentration is present in human tissues and performs a number of important and useful functions, extremely difficult. Similar aspects are discussed in the section on immunology. But according to experts, everyone, especially parents, needs to understand the basics of the immune system.

The fact is that the vast majority of various drugs that affect the functional activity of the immune system are sold in pharmacies without a doctor's prescription. However, their use is far from always justified, and in some cases, on the contrary, can cause negative consequences. Therefore, in the absence of any serious manifestations of immunodeficiency, it is better to strengthen the body's defenses with the help of readily available means, lifestyle changes, etc.

In general, immunology began to actively develop only in recent decades. The impetus for conducting a huge number of clinical studies was the emergence of quite serious diseases, with which human immunity is often unable to cope. First of all, it is HIV, also life-threatening strains of the influenza virus that often take on pandemic proportions. As a result, much more is now known about the functioning of the immune system, its role in the development of allergies, autoimmune pathologies, and malignant tumors. New methods of therapy are emerging.

Varieties

Immunity - a feature of the body to resist pathogenic agents (bacteria, viruses, fungi). Its formation, "ability" to differentiate (distinguish) its own cells from those that threaten life and health occurs even in the early stages of fetal development in the womb. Such immunity is called congenital. This group also includes the immunity of the human body to some infections that are typical only for the animal world.

However, from the first minutes of life, a child is faced with the influence of a huge number of pathogens, as a result of which the formation of acquired (adaptive) immunity begins.

He can be:

natural active, which occurs after an illness, a vivid example is the antiviral protection that appears as a result of chickenpox, measles, mumps, etc.;
natural passive, due to the intrauterine "transfer" of protective bodies (antibodies) from mother to fetus during pregnancy, which is why vaccination of the child begins several months after childbirth;
artificially active, formed after the introduction of vaccines (preparations contain minimal concentrations of pathogenic antigens that provoke the production of specific antibodies), as a result, a person remains immune to certain diseases (measles, rubella, poliomyelitis, etc.), in some cases, to achieve the desired result, vaccination is repeated several times with a strictly defined interval;
artificial passive, formed when already developed antibodies are introduced into the human body (found in the blood of humans and animals) against a specific disease, such as rabies injections after being bitten.

Also, immunity can be specific or non-specific. Nonspecific consists of defense mechanisms that are "turned on" after contact of the body with any pathogenic factor. Specific protection arises as a result of vaccination, it is directed against a specific antigen (causative agent of rubella, tuberculosis, etc.).

It is important

The correct combination of specific and non-specific immunity determines the homogeneity of the antigenic composition. And the deviation in one direction or another provides a decrease in anti-infectious and antitumor protection.

Features of the functioning of the innate immune system

The basis of innate immunity is formed by a variety of barriers, the function of which is to prevent the penetration of pathogenic microorganisms into human tissue. It:

epidermal cover and secretion of the glands of external secretion;
the secret of the mucous epithelium (in particular, the pH level, the content of lysozyme);
villi of the respiratory tract.

The next link of innate immunity is cellular, which includes several types of leukocytes:

Mononuclear phagocytes (monocytes and macrophages). On the one hand, these structures provide phagocytosis (absorption of pathogenic microorganisms and their further destruction) and other mechanisms of nonspecific immunity, and on the other hand, initiate specific protection by interacting with T-lymphocytes. But in addition to phagocytosis, macrophages also have secretory activity, releasing tumor necrosis factor, interleukins, α-interferon and some other biological compounds.
Granulocytes (eosinophils, basophils, neutrophils). Neutrophils are concentrated in the focus of the pathology, also providing phagocytosis and secretory function. These cells can also activate both the coagulation and anticoagulant systems of the blood, sometimes causing damage to the surrounding protein structures. Eosinophils help get rid of large pathological microorganisms (for example, parasites). Basophils are found in the circulating blood and tissues (connective tissue, vascular wall, skin, lungs, mucous membranes). The latter are also called mast cells. Provide specific biochemical reactions with the participation of immunoglobulin (Ig) E, which externally manifests itself in the form of local hyperthermia, redness, edema.
"Killer" cells (EK-, K- and LAK - cells). According to experts, EK - cells perform a kind of role of immunological surveillance, "acting" against tumor cells and infectious agents. Also, these cells secrete α- and γ-interferons, interleukins, lymphotoxins. K- and LAK-cells also perform the function of killing pathogenic cells.

It is important

According to experts, K-cells play an important role in the pathogenesis of many autoimmune diseases.

Another factor of nonspecific innate immunity is humoral. During clinical studies, it was noted that human serum destroys certain gram-negative bacteria. This is explained by the presence of certain natural antibodies that destroy the wall of pathogens and lead to their irreversible death.

Humoral protection is provided by:

interferons, which protect neighboring cells and tissues from damage by various viruses;
properdin, activates complementary immune defense mechanisms;
β-lysine, released during the destruction of platelets and fights against gram-positive flora;
lactoferrin, has the ability to bind iron, which is necessary for the life of a bacterial cell;
lysozyme, which is also part of mucous secretions, has antimicrobial activity.

However, innate immunity does not have an immunological memory, in other words, infection with the same pathogen can occur again.

More about immunity

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Congenital
Weak immunity in an adult

Acquired specific

Also presented:

humoral, includes B - lymphocytes and immunoglobulins produced by them;
cellular, consisting of T-lymphocytes (helpers, killers and suppressors).

A distinctive feature of acquired immunity is the ability to divide antigens into their own and foreign ones. In addition, with repeated exposure to the same pathogen, immune responses develop much faster, which often makes it possible to shorten the duration of the disease or avoid it altogether.

Maintaining the functions of acquired immunity is provided by central and peripheral organs:

spleen;
lymph nodes;
lymphopharyngeal ring located in the oral cavity;
mucous membranes;
lymphatic cells circulating in the bloodstream;
thymus gland (thymus);
bone marrow.

Like any other organ of the body, the immune system is subject to the aggressive influence of factors of the external and internal environment, largely depends on the lifestyle and nutrition. Medication recovery of reduced body defenses with the appointment of a variety of drops, tablets or injections is best done on the recommendation of a doctor.

Increased susceptibility to various kinds of infectious and viral diseases is not always a sign of immunodeficiency and requires treatment. In most cases, you can do with strengthening procedures, tinctures of medicinal plants, adding a number of vitamin-rich foods (lemon, honey, ginger, etc.) to the diet.

The immune system: when to talk about immunodeficiency, the reasons for the weakening of the body's defenses

When a foreign agent (antigen) enters the body, for example, rino- or adenovirus, the first in the immune response Macrophages (they are also called antigen-transmitting cells) are "turned on", which further bind the antigen with a specific HLA - proteins. As a result, a chain of biochemical reactions, regulated by enzymes, begins, which ultimately leads to the production of interleukins (in particular, IL-1).

In turn, IL-1 interacts with CD4 + receptors located on the surface of helper T-lymphocytes. Th1 - cells in response to produce interferons and other types of interleukins (IL-2 and IL-3), and Th2 - cells "start" the active production of B-lymphocytes, neutrophils and other reactions of cellular and humoral immunity.

The resulting antibodies bind to antigens, removing them from the body, and the cells affected by the virus are destroyed. At the same time, tissue regeneration processes are stimulated.

However, this reaction of the body is not universal. Some viruses (for example, influenza) have the property of antigenic variability. Roughly speaking, getting into the body, the structure of the antigen can change, which "helps" to avoid the destructive effect of antibodies. For herpes (affecting the structures of the central and peripheral nervous system, skin and mucous membranes integument) is characterized by a latent course with constantly occurring relapses against the background of a weakening of protective forces organism. A number of viruses directly affect the immune system (Epstein-Barr, measles, HIV, Dengue hemorrhagic fevers, Lassa, Ebola).

Antibacterial immunity "works" in a different way, since these microorganisms undergo phagocytosis, and such reactions also take place with the participation of T-helpers. However, bacteria have also "adapted" to survive in tissues. For example, the causative agent of Lyme disease is also characterized by antigenic variability, therefore, without treatment, the pathology can recur up to 10 times. Some pathogens produce substances that protect them from death inside macrophages.

What is good and what is bad

The main sign of immunodeficiency are frequent viral diseases, which often occur with bacterial complications. Wherein:

pathology is sluggish;
the duration of the acute stage of the disease exceeds 5 to 7 days;
standard methods of therapy do not bring the expected result;
even after the normalization of the temperature and general well-being, residual symptoms (cough, runny nose, sore throat, etc.) continue to bother.

Also, a person complains about:

frequent relapses of herpes, the appearance of papillomas, warts on the body;
lethargy, weakness, and fatigue;
frequent mycoses of various localization;
enlargement and soreness of the lymph nodes.

A fully functioning immune system provides adequate protection against the development of infections, a quick recovery. But in some cases, violations of immunity do not cause a weakening of the body's defenses, but, on the contrary, their excessive reactivity.

In this case, the likelihood of developing:

Allergies. This is a hypersensitivity reaction to certain kinds of substances that are harmless to a healthy person. The body of an allergic person perceives them as antigens, which is accompanied by an immune response. In some cases, such "failures" in the body can become critical, causing life-threatening conditions, such as anaphylactic shock.
Autoimmune pathologies. To date, the final pathogenesis, as well as the provoking cause of such diseases, are not known. However, symptoms appear as a result of an overactive immune response to its own cells, which leads to damage to various organs and tissues (lupus, rheumatoid arthritis, glomerulonephritis and etc.). Treatment of such pathologies consists in the appointment of steroid hormones in the acute phase of the disease for suppression of the inflammatory process and cytostatics, which artificially inhibit the activity of the immune systems. Often prescribed use Puri Netol.

There are many factors that can cause a weakening of the immune system. The most significant among them are:

congenital and acquired features of the anatomy and physiology of internal organs (changes in the structure of the mucous membranes, dysbiosis, etc.);
improper diet, which leads to a deficiency of vitamins, minerals and amino acids;
chronic fatigue;
insufficient and excessive physical activity;
constant exposure to stress factors;
certain diseases (for example, diabetes mellitus), age-related changes in the body;
lifestyle (physical inactivity, addiction to alcohol and nicotine).

The ecological situation and the influence of occupational hazards are also of great importance. Certain medications also cause immunodeficiency.

Stimulation of immunity: methods of increasing protection against infections, the state of immunity during pregnancy, in childhood and old age

The most popular and simplest way to improve immunity are drugs specially designed for these purposes. There are many groups immunomodulators (bacterial, synthetic, interferon and its inducers), which affect various parts of the immune system. Some of them are approved for use at an early age.

The most in demand are:

Interferons. Contains recombinant human interferon and prevents further spread of the virus. They are most effective in the initial stages of diseases. These are leukocyte interferon, Ingaron, Viferon, Nazoferon, etc.
Interferon inducers. Stimulates the production of their own interferon. This class includes Kagocel, Amiksin, Neovir, etc.
Bacterial drugs. Contain lysates of microbial cells, which increases the degree of immune defense against certain pathogens (usually affecting the nasopharynx). For example, IRS 19, Imudon, Broncho-Munal).
Other preparations of synthetic structure (Arbidol, Galavit, Alokin-Alpha, etc.).

However, the use of such medications should be medically indicated due to the risk of side effects.

A variety of herbal preparations, dietary supplements and multivitamin complexes are safer in this regard:

Immunal and other preparations containing echinacea extract;
Akulavit, contains shark liver oil, which is distinguished by immunostimulating activity;
Stimmunal, contains echinacea and ascorbic acid;
Rioflora Immuna Neo, contains lactobacilli and minerals;
multivitamins (Multi Tabs Immuno Plus, Alphabet in the season of colds, etc.).

The diet is very important, which must include greens, vegetables, fruits, freshly squeezed juices, dairy products. Compulsory moderate physical activity. A good result is given by hardening procedures, which are best done in the warm season, when a person is completely healthy.

In folk medicine, it is proposed to stimulate immunity:

rose hips;
ginger;
lemon;
garlic;
chamomile;
rhodiola pink;
honey and other beekeeping products.

It is very important to support the body's defenses during pregnancy, when it is undesirable to take any medications. Therefore, doctors recommend gymnastics, long walks. You also need proper nutrition and adherence to hygiene and prevention measures. Doctors give similar recommendations on strengthening immunity in children. Frequent walks, sports, active games and a full diet will help prevent illness.

In old age, the stimulation of immunity is also not the last place. The body is advised to "help" with fortifying drugs. It is also necessary to undergo regular medical examinations. For the prevention of immunodeficiency, it is necessary to abandon self-medication, monitor nutrition, play sports and lead an active lifestyle.

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