The immune system kills the body. How to raise an antitumor immune cell

Scientists hope to find the causes of autoimmune diseases at the molecular genetic level.
Reuters photo

The immune system is designed to protect the body. But in some situations, its functioning is disrupted, and immune defense factors become aggressors in relation to the body's own tissues. The treatment of such autoimmune diseases is of great difficulty: the main goal of therapy is a balance between reducing the activity of the immune system against one's own body and maintaining immunity.

One such disease is systemic lupus erythematosus. This is a severe systemic disease of the connective tissue, in which various internal organs are affected. The disease has been known since antiquity, and got its name because of the characteristic rash on the bridge of the nose and cheeks, reminiscent of wolf bites. 90% of patients are women aged 20-40 years. In Russia, the number of patients with systemic lupus erythematosus increases annually and is already approaching 80 thousand, and in 40 thousand the disease is steadily progressing and leads to early disability and death.

The cause of lupus is unknown. In developed countries, on average, 3.5 years after diagnosis, 40% of patients are forced to stop working. Patients have lesions of the skin, joints, muscles, mucous membranes, heart, lungs, nervous system more than half have kidney damage. Periods of exacerbation are replaced by remission, but there is also an active, constantly progressive course.

The problems of systemic lupus erythematosus were discussed at a conference held at the Research Institute of Rheumatology of the Russian Academy of Medical Sciences in Moscow.

The molecular genetic basis of the disease is poorly understood, so until recently there was no specific treatment. Academician of the Russian Academy of Medical Sciences Evgeny Nasonov, director of the Research Institute of Rheumatology of the Russian Academy of Medical Sciences, emphasized that the entire arsenal of drugs used in rheumatology is used to treat systemic lupus erythematosus. medicines, including non-steroidal anti-inflammatory drugs, hormones, anti-cell dividing agents, anti-malarial drugs, and even extracorporeal blood purification methods. Most of them are used in systemic lupus erythematosus for off-label indications.

Understanding the need to improve the pharmacotherapy of systemic lupus erythematosus has become an incentive for large-scale clinical trials. various means. And first of all - genetically engineered biological preparations.

Immunological control over pathogenetic mechanisms became possible with the discovery of a molecular pathway, by acting on which it is possible to restrain the development of systemic lupus erythematosus to some extent. This pathway involves a protein called B-lymphocyte stimulator (BLyS), from the tumor necrosis factor family. It was found that the suppression of BLyS allows you to somewhat contain the flared immune system.

The researchers, wanting to specifically block BLyS, relied on a human monoclonal antibody called belimumab. Against the background of its use, a decrease in the overall frequency of exacerbations and severe exacerbations of the disease was observed.

Academician Yevgeny Nasonov noted that Russian rheumatological centers in Moscow, St. Petersburg and Yaroslavl took part in the clinical trial of the belimumab monoclonal antibody. Its development is inextricably linked with progress fundamental research in the field of immunopathology of human diseases and is a prime example of the practical implementation of the concept of translational medicine. You can talk about opening new era in the treatment of systemic lupus erythematosus, associated with the beginning of the widespread use of genetically engineered biological agents and the creation of a new class of drugs - BLyS inhibitors, which may have an important therapeutic potential not only in systemic lupus erythematosus, but also in a wide range of human autoimmune diseases.

About 5% of the world's population suffers from autoimmune diseases, a condition in which own cells the body's immune system, instead of fighting pathogens, destroy normal cells of organs and tissues. In this article, which precedes the special project on autoimmune diseases, we will look at the basic principles of the immune system and show why such sabotage on its part is possible.

With this article, we begin a cycle on autoimmune diseases - diseases in which the body begins to fight with itself, producing autoantibodies and / or autoaggressive clones of lymphocytes. We will talk about how the immune system works and why sometimes it starts to "shoot at its own." Some of the most common diseases will be covered in separate publications. To maintain objectivity, we invited Doctor of Biological Sciences, Corr. RAS, Professor of the Department of Immunology, Moscow State University Dmitry Vladimirovich Kuprash. In addition, each article has its own reviewer, delving into all the nuances in more detail. The reviewer of this - introductory - article was Evgeny Sergeevich Shilov, candidate of biological sciences, researcher of the same department.

Antigens- any substances that the body perceives as foreign and, accordingly, responds to their appearance by activating the immune system. The most important antigens for the immune system are pieces of molecules located on the outer surface of the pathogen. These pieces can be used to determine which one the aggressor attacked the body, and provide a fight against it.

Cytokines - Morse code of the body

In order for immune cells to coordinate their actions in the fight against the enemy, they need a system of signals that tell who and when to join the battle, or end the battle, or, conversely, resume it, and much, much more. For these purposes, cells produce small protein molecules - cytokines, for example, various interleukins(IL-1, 2, 3, etc.) . It is difficult to assign an unambiguous function to many cytokines, however, with some degree of conventionality, they can be divided into five groups: chemokines, growth factors, about inflammatory, counter inflammatory and immunoregulatory cytokines.

The above classification conditionality means that a cytokine included in one of the listed groups, under certain conditions in the body, can play a diametrically opposite role - for example, it can turn from pro-inflammatory into anti-inflammatory.

Without an established connection between the types of troops, any ingenious military operation is doomed to failure, therefore, it is very important for the cells of the immune system, when receiving and giving orders in the form of cytokines, to interpret them correctly and act in a coordinated manner. If cytokine signals begin to be produced in a very large amount, then panic sets in in the cell rows, which can lead to damage to one's own body. It is called cytokine storm: in response to incoming cytokine signals, the cells of the immune system begin to produce more and more of their own cytokines, which, in turn, act on the cells and increase the secretion of themselves. A vicious circle is formed, which leads to the destruction of surrounding cells, and later neighboring tissues.

Count in order! immune cells

As in the armed forces there are different types of troops, so the cells of the immune system can be divided into two large branches - innate and acquired immunity, for the study of which in 2011 was awarded Nobel Prize , . innate immunity- that part of the immune system that is ready to defend the body immediately, as soon as a pathogen attacks. Acquired same (or adaptive) the immune response at the first contact with the enemy unfolds longer, as it requires ingenious preparation, but after that it can carry out a more complex scenario of protecting the body. Innate immunity is very effective in the fight against single saboteurs: it neutralizes them without disturbing specialized elite military units - adaptive immunity. If the threat turned out to be more significant and there is a risk of the pathogen penetrating deeper into the body, the cells of the innate immunity immediately signal this, and the cells of the acquired immunity enter the battle.

All immune cells in the body are made in the bone marrow. hematopoietic stem cell, which gives rise to two cells - general myeloid And common lymphoid progenitor, . Acquired immunity cells are derived from a common lymphoid progenitor and are accordingly called lymphocytes, while innate immune cells may originate from both progenitors. The scheme of cell differentiation of the immune system is shown in Figure 1.

Figure 1. Scheme of cell differentiation of the immune system. hematopoietic stem cell gives rise to cells - precursors of myeloid and lymphoid lines of differentiation, from which all types of blood cells are further formed.

Innate Immunity - Regular Army

Innate immune cells recognize a pathogen by its specific molecular markers, the so-called images of pathogenicity. These markers do not make it possible to accurately determine the belonging of a pathogen to a particular species, but only signal that the immune system has encountered strangers. For our body, fragments of the cell wall and flagella of bacteria, double-stranded RNA and single-stranded DNA of viruses, etc. can serve as such markers. With the help of special innate immune receptors such as TLR ( Toll-like receptors, Toll-like receptors) and NLR ( Nod-like receptors, Nod-like receptors), cells interact with patterns of pathogenicity and begin to implement their defense strategy.

Now let's take a closer look at some of the cells of the innate immune system.

In order to understand how the T-cell receptor works, we must first discuss a little about another important family of proteins - major histocompatibility complex(MHC, major histocompatibility complex) . These proteins are the molecular "passwords" of the body, allowing the cells of the immune system to distinguish their compatriots from the enemy. In any cell, the process of protein degradation is constantly going on. Special Molecular Machine - immunoproteasome- cleaves proteins into short peptides that can be built into the MHC and, like an apple on a plate, presented to the T-lymphocyte. With the help of TCR, the peptide “sees” and recognizes whether it belongs to the body’s own proteins or is foreign. At the same time, the TCR checks whether the MHC molecule is familiar to it, which allows it to distinguish its own cells from "neighboring" ones, that is, cells of the same species, but of another individual. It is the coincidence of MHC molecules that is necessary for the engraftment of transplanted tissues and organs, hence the tricky name: histos in Greek means "cloth". In humans, MHC molecules are also called HLA ( human leukocyte antigen- human leukocyte antigen).

Video 2. Short-term interactions of T cells with a dendritic cell (indicated green).

T-lymphocytes

To activate a T-lymphocyte, it needs to receive three signals. The first of these is the interaction of TCR with MHC, that is, antigen recognition. The second is the so-called co-stimulatory signal transmitted by the antigen-presenting cell through CD80/86 molecules to CD28 located on the lymphocyte. The third signal is the production of a cocktail of many pro-inflammatory cytokines. If any of these signals break down, it is fraught with serious consequences for the body, for example, an autoimmunity reaction.

There are two types of major histocompatibility complex molecules: MHC-I and MHC-II. The first is present on all cells of the body and carries the peptides of cellular proteins or proteins of the virus that infected it. Special subtype of T-cells - T-killers(they are also called CD8 + T-lymphocytes) - interacts with its receptor with the MHC-I-peptide complex. If this interaction is strong enough, it means that the peptide that the T-cell sees is not characteristic of the organism and, accordingly, may belong to the enemy that has invaded the cell - the virus. There is an urgent need to neutralize the intruder, and the T-killer does an excellent job of this task. It, like the NK cell, secretes the proteins perforin and granzyme, which leads to the lysis of the target cell.

T-cell receptor of another subtype of T-lymphocytes - T-helpers(Th-cells, CD4+ T-lymphocytes) - interacts with the MHC-II-peptide complex. This complex is not found on all cells of the body, but mainly on immune cells, and the peptides that can be presented by the MHC-II molecule are fragments of pathogens captured from the extracellular space. If the T-cell receptor interacts with the MHC-II-peptide complex, then the T-cell begins to produce chemokines and cytokines that help other cells to effectively carry out their function - the fight against the enemy. That is why these lymphocytes are called helpers - from English helper(assistant). Among them, many subtypes are distinguished, which differ in the spectrum of cytokines produced and, therefore, in their role in the immune process. For example, there are Th1 lymphocytes that are effective in fighting intracellular bacteria and protozoa, Th2 lymphocytes that help B cells work and are therefore important for resisting extracellular bacteria (which we will talk about shortly), Th17 cells, and many others.

Video 3. Movement of T-helpers ( red) and T-killers ( green) in the lymph node. The video was filmed using intravital two-photon microscopy.

Among CD4+ T cells, there is a special subtype of cells - regulatory T-lymphocytes. They can be compared with the military prosecutor's office, which restrains the fanaticism of soldiers rushing into battle and does not allow them to harm the civilian population. These cells produce cytokines overwhelming immune response, and thus weaken the immune response when the enemy is defeated.

The fact that the T-lymphocyte recognizes only foreign antigens, and not molecules of its own body, is the result of an ingenious process called selection. It occurs in an organ specially created for this - the thymus, where T cells complete their development. The essence of selection is as follows: the cells surrounding a young, or naive, lymphocyte show (present) to it the peptides of their own proteins. The lymphocyte that recognizes these protein fragments too well or too poorly is destroyed. The surviving cells (and this is less than 1% of all T-lymphocyte precursors that entered the thymus) have an intermediate affinity for the antigen, therefore, as a rule, they do not consider their own cells as targets for attack, but are able to respond to a suitable foreign peptide. Selection in the thymus is the mechanism of the so-called central immunological tolerance.

There is also peripheral immunological tolerance. With the development of infection, the dendritic cell, as well as any cell of innate immunity, is affected by images of pathogenicity. Only then can it mature, begin to express additional molecules on its surface to activate the lymphocyte and effectively present antigens to T-lymphocytes. If a T-lymphocyte encounters an immature dendritic cell, then it is not activated, but self-destructs or is suppressed. This inactive state of the T cell is called energy. In this way, the pathogenic action of autoreactive T-lymphocytes, which, for one reason or another, survived during selection in the thymus, is prevented in the body.

All of the above applies to αβ-T-lymphocytes, however, there is another type of T-cells - γδ-T-lymphocytes(the name determines the composition of the protein molecules that form the TCR). They are relatively few in number and mainly inhabit the intestinal mucosa and other barrier tissues, playing a critical role in regulating the composition of the microbes living there. In γδ-T cells, the antigen recognition mechanism differs from that of αβ-T lymphocytic and is independent of TCR.

B-lymphocytes

B-lymphocytes carry the B-cell receptor on their surface. Upon contact with the antigen, these cells are activated and turn into a special cell subtype - plasma cells, which have the unique ability to secrete their B-cell receptor into the environment - these are the molecules we call antibodies. Thus, both the BCR and the antibody have an affinity for the antigen they recognize, as if “sticking” to it. This allows antibodies to envelop (opsonize) cells and viral particles coated with antigen molecules, attracting macrophages and other immune cells to destroy the pathogen. Antibodies are also able to activate a special cascade of immunological reactions called complement system, which leads to perforation of the cell membrane of the pathogen and its death.

For an effective meeting of adaptive immunity cells with dendritic cells, which carry foreign antigens as part of the MHC and therefore work as "connectors", there are special immune organs in the body - lymph nodes. Their distribution throughout the body is heterogeneous and depends on how vulnerable this or that border is. Most of them are located near the digestive and respiratory tracts, because the penetration of the pathogen with food or inhaled air is the most likely way of infection.

Video 4. Translocation of T cells (labeled red) in the lymph node. Cells that form the structural basis of the lymph node and the walls of blood vessels are labeled with green fluorescent protein. The video was filmed using intravital two-photon microscopy.

The development of an adaptive immune response takes a long time (from several days to two weeks), and in order for the body to defend itself against an already familiar infection faster, the so-called memory cells. They, like veterans, are present in the body in small numbers, and if a pathogen familiar to them appears, they reactivate, quickly divide, and go out to defend the borders with a whole army.

The logic of the immune response

When the body is attacked by pathogens, the cells of innate immunity - neutrophils, basophils and eosinophils - first of all come into battle. They release the contents of their granules outside, which can damage the bacterial cell wall, and also, for example, increase blood flow so that as many cells as possible rush to the site of infection.

At the same time, the dendritic cell, which has absorbed the pathogen, hurries to the nearest lymph node, where it transmits information about it to the T- and B-lymphocytes located there. Those are activated and travel to the location of the pathogen (Fig. 2). The battle rages on: T-killers, upon contact with an infected cell, kill it, T-helpers help macrophages and B-lymphocytes to carry out their defense mechanisms. As a result, the pathogen dies, and the victorious cells go to rest. Most of them die, but some become memory cells that settle in the bone marrow and wait for the body to need their help again.

Figure 2. Scheme of the immune response. A pathogen that enters the body is detected by a dendritic cell that moves to the lymph node and there transmits information about the enemy to T and B cells. They are activated and released into tissues, where they realize their protective function: B-lymphocytes produce antibodies, T-killers, with the help of perforin and granzyme B, carry out contact killing of the pathogen, and T-helpers produce cytokines that help other cells of the immune system in the fight against it.

This is how any immune response looks like, but it can change markedly depending on which particular pathogen has entered the body. If we are dealing with extracellular bacteria, fungi or, say, worms, then the main armed forces in this case will be eosinophils, B cells that produce antibodies, and Th2 lymphocytes that help them in this. If intracellular bacteria have settled in the body, then macrophages, which can absorb the infected cell, and Th1-lymphocytes, which help them in this, rush to the rescue first of all. Well, in the case of a viral infection, NK cells and T-killers enter the battle, which destroy the infected cells by contact killing.

As we can see, the variety of types of immune cells and mechanisms of their action is not accidental: for each type of pathogen, the body has its own effective method struggle (Fig. 3).

Figure 3. Main types of pathogens and cells involved in their destruction.

And now all the above-described immune twists and turns - in a short video.

Video 5. The mechanism of the immune response.

Civil war rages...

Unfortunately, no war is complete without civilian casualties. A long and intense defense can cost the body dearly if aggressive highly specialized troops get out of hand. Damage to the body's own organs and tissues by the immune system is called autoimmune process. Approximately 5% of humanity suffers from this type of disease.

The selection of T-lymphocytes in the thymus, as well as the removal of autoreactive cells in the periphery (central and peripheral immunological tolerance), which we discussed earlier, cannot completely rid the body of autoreactive T-lymphocytes. As for B-lymphocytes, the question of how strictly their selection is carried out still remains open. Therefore, in the body of each person there are necessarily many autoreactive lymphocytes, which, in the event of an autoimmune reaction, can damage their own organs and tissues in accordance with their specificity.

Both T- and B-cells can be responsible for autoimmune damage to the body. The former carry out the direct killing of innocent cells that carry the corresponding antigen, and also help autoreactive B cells in the production of antibodies. T-cell autoimmunity has been well studied in rheumatoid arthritis, type 1 diabetes, multiple sclerosis, and many other diseases.

B-lymphocytes act much more sophisticatedly. First, autoantibodies can cause cell death by activating the complement system on their surface or by attracting macrophages. Second, receptors on the cell surface can become targets for antibodies. When such an antibody binds to a receptor, it can either be blocked or activated without a real hormonal signal. This is what happens with Graves' disease: B-lymphocytes produce antibodies against the receptor for TSH (thyroid-stimulating hormone), mimicking the action of the hormone and, accordingly, increasing the production of thyroid hormones. In myasthenia gravis, antibodies against the acetylcholine receptor block its action, which leads to impaired neuromuscular conduction. Thirdly, autoantibodies, together with soluble antigens, can form immune complexes that settle in various organs and tissues (for example, in the renal glomeruli, joints, vascular endothelium), disrupting their work and causing inflammation.

As a rule, an autoimmune disease occurs suddenly, and it is impossible to determine exactly what caused it. It is believed that almost any stressful situation can serve as a trigger for launching, whether it is an infection, injury or hypothermia. A significant contribution to the likelihood of an autoimmune disease is made both by a person's lifestyle and genetic predisposition - the presence of a certain variant of a gene.

Predisposition to a particular autoimmune disease is often associated with certain alleles of the MHC genes, which we have already talked about a lot. So, the presence of an allele HLA-B27 can serve as a marker of predisposition to the development of ankylosing spondylitis, juvenile rheumatoid arthritis, psoriatic arthritis and other diseases. Interestingly, the presence in the genome of the same HLA-B27 correlates with effective protection against viruses: for example, carriers of this allele have a reduced chance of contracting HIV or hepatitis C,. This is another reminder that the more aggressively an army fights, the more likely civilian casualties are.

In addition, the level of autoantigen expression in the thymus can influence the development of the disease. For example, the production of insulin and, accordingly, the frequency of presentation of its antigens to T cells differs from person to person. The higher it is, the lower the risk of developing type 1 diabetes, as this allows the removal of insulin-specific T-lymphocytes.

All autoimmune diseases can be divided into organ-specific And systemic. In organ-specific diseases, individual organs or tissues are affected. For example, in multiple sclerosis, the myelin sheath of neurons, in rheumatoid arthritis, the joints, and in type 1 diabetes, the islets of Langerhans in the pancreas. Systemic autoimmune diseases are characterized by damage to many organs and tissues. Such diseases include, for example, systemic lupus erythematosus and primary Sjögren's syndrome, which affect connective tissue. More details about these diseases will be discussed in other articles of the special project.

Conclusion

As we have already seen, immunity is a complex network of interactions both at the cellular and molecular levels. Even nature could not create an ideal system that reliably protects the body from pathogen attacks and at the same time under no circumstances damages its own organs. Autoimmune diseases - by-effect the high specificity of the work of the adaptive immunity system, the costs that we have to pay for the opportunity to successfully exist in a world teeming with bacteria, viruses and other pathogens.

Medicine - the creation of human hands - cannot fully correct what was created by nature, therefore, to date, none of the autoimmune diseases can be completely cured. Therefore, the goals that modern medicine seeks to achieve are the timely diagnosis of the disease and the effective relief of its symptoms, on which the quality of life of patients directly depends. However, for this to be possible, public awareness of autoimmune diseases and their treatment needs to be increased. "Forewarned is forearmed!"- that's the motto public organizations created for this around the world.

Literature

1. Mark D. Turner, Belinda Nedjai, Tara Hurst, Daniel J. Pennington. (2014). Cytokines and chemokines: At the crossroads of cell signaling and inflammatory disease . Biochimica et Biophysica Acta (BBA) - Molecular Cell Research. 1843 . Focus on 50 years of B cells. (2015). Nat. Rev. Immun. 15 ;

The period of cold weather has not yet arrived, and you are already suffering from a runny nose? During the winter, do you manage to get the flu 2-3 times? Most likely, the cause of the disease lies in a weakened immune system. It is no secret that immunity is on the protection of our body, preventing viral and any other diseases. And if for any reason this protection is weakened, the attacks of viruses and bacteria can achieve their insidious goal. Moreover, one should not think that only a serious illness, an operation, or exhaustion of the body leads to a weakening of the immune system. Sometimes unhealthy habits that Everyday life we do not even notice, significantly weaken the immune system.

12 invisible things that destroy our immunity

1. Lack of sleep

Insomnia is one of the most common causes of weakened immunity. The lack of a regimen, being busy at work, stress, or depression - all these factors interfere with the proper rest of the body, preventing you from getting enough sleep. According to research by the National Heart Institute, in the body of people who regularly sleep 4 hours a day or even less, 2 times less antibodies are produced to fight the common cold. Sleep deprivation significantly weakens the body's natural defenses, and therefore review the rest regimen with an increase in sleep time to at least 8 hours.

2. Alcohol abuse

According to research from the National Institutes of Health, excessive alcohol consumption negatively affects health, in particular, impairs mental processes, leads to sleep problems and disrupts the absorption of nutrients. In addition, regular consumption of alcoholic beverages inhibits the reproduction of blood cells that protect the body. Add to this the fact that alcohol destroys liver cells, which are designed to cleanse the blood of harmful substances. As a result of this process, toxins and toxins remain in the body, which significantly weakens the immune system.

Think also about the fact that alcohol negatively affects vascular system, significantly reducing life expectancy, and can cause oncology. Is it worth shortening your life for the dubious pleasure of a glass of wine or a glass of vodka?

Smoking is known to significantly increase the likelihood of developing bronchitis and other infections. respiratory system. Scientists studied the state of lymphocytes in all organs and systems of the body of a smoker, and came to the conclusion that smoking significantly inhibits cellular immunity. Moreover, the maximum damage from this bad habit carry pulmonary lymphocytes, which in the early stages threatens the smoker infectious diseases and eventually lead to lung cancer.

Moreover, getting into the blood or saliva of a person, nicotine reduces the amount of immunoglobulins - proteins that form an immune response. As a result, the body simply misses the attack of viruses, not having time to react and prevent the disease.

4. Abuse of sugar

According to scientists, the abuse of sugar reduces the body's defenses by more than 40%. Studies show that eating sugar in just 10 minutes weakens the immune system, and this process continues for several hours. This happens because an increase in blood glucose levels destroys vitamin C and disrupts the structure of immune cells. In this regard, each person should think about reducing sugar intake to 50 g per day, because in addition to weakening the immune system, the abuse of this product leads to the development of caries, obesity and hypertension, thereby increasing the risk of coronary heart disease.

5. Lack of exercise

It's no secret that the increase in heart rate caused by exercise, stimulates blood circulation and improves oxygen supply to organs and tissues. In addition, when playing sports, breathing quickens, which helps to remove viruses and bacteria from the body. However, this is not all. During exercise, body temperature rises, leading to the death of pathogenic microflora. All this has a beneficial effect on the state of the body, which increases resistance to infections. If a person does not play sports, blood circulation decreases, the body accumulates toxins and becomes stressed. All this leads to a decrease in immunity, and hence to various diseases.

To increase the body's resistance to infections, it is enough to play sports three times a week - jogging, swimming, playing tennis, cycling, in general, getting moderate exercise that will allow you to forget about seasonal colds.

6. Lack of hygiene

Washing your hands in the morning and evening is not enough to fully combat germs. You need to wash them before every meal, after transport and coming from the street, after shaking hands, and also after any work. Ideally, keep hand sanitizer in your purse or car at all times and use it on your skin for at least 20 seconds. Brushing your teeth alone is also not enough, you need to clean the tongue from plaque, in which microbes actively multiply, and clean the space between the teeth with an irrigator. It is also required to clean the nasal mucosa by rinsing with cool water. All this will reduce the number of pathogens entering the body, and therefore will not allow a decrease in the body's defenses.

7. Lack of Immunity Boosting Foods in the Diet

Regular hand washing is certainly a useful measure in the fight for a healthy immune system. However, the main role in strengthening the body's defenses is played by proper nutrition. To maintain immunity, it is enough to regularly consume foods that increase the body's defenses. We list the products that provide the body with useful substances:

• proteins (eggs, meat, dairy products, nuts and mushrooms);
• zinc (liver, shrimp, beans and green peas);
• iodine (seafood, tomatoes, carrots and asparagus);
• selenium (cereals, seeds, mushrooms and brewer's yeast);
• dietary fiber (bran, legumes, oatmeal and apples);
• lacto- and bifidobacteria (soaked apples, sauerkraut, dairy products).
• vitamin A (carrots, apples, fish fat, butter);
• vitamin B (millet, rye bread, eggs and greens);
• vitamin C (lemons, oranges, cranberries, rose hips);
• vitamin E (olive, corn, sunflower and other oils).

8. Working the night shift

A person who regularly works night shifts is faced with such a problem as a lack of vitamin D - a valuable substance that we all get from sunlight. Deficiency of this vitamin becomes another blow to the immune system. To avoid this, try to be in the sun for at least 15-20 minutes a day.

9. Lack of cleaning in the apartment

Even a full sleep will not provide the necessary protection to the body if you sleep in an unventilated room. Stale air and a large amount of dust plays into the hands of microbes, which ultimately leads to frequent diseases. To prevent colds and flu, it is important not only to monitor your own hygiene, but also to fight germs on the approaches to the body, which means regular cleaning in the apartment. To do this, daily wipe flat surfaces from dust, disinfect door handles, a computer mouse and keyboard, ventilate the room and wash the floors.

10. Pessimistic attitude

You may not have thought about the fact that mood can affect the state of health, but scientists unanimously say that a pessimistic attitude negatively affects the body, creating the prerequisites for the appearance various diseases. Cortisol is the culprit, the stress hormone, the increased production of which destroys the cells of the immune system. How to counter this? Very simple! Look for the positive in everything you see, find reasons to have fun, enjoy every day, meet friends more often and spend more time with your family who will give you the support you need. And also read the classics who knew a lot about humor - Chekhov, Zoshchenko and Averchenko. Remember, laughter prolongs life!

11. Antibiotic abuse

Such a pharmacological group of drugs as antibiotics was developed almost 100 years ago exclusively to fight bacteria. But today there is a real boom in the popularity of antibiotics, which are often used as a remedy for all diseases. But taking antibiotics without a doctor's prescription and trying to cure viral or fungal diseases with them, a person, of course, does not get the desired result, but the intestinal microflora “kills” thoroughly. This leads to a decrease in the immune defense of the body. There can be only one advice here - take antibacterial drugs as rarely as possible, and only at the insistence of a doctor.

12. No allergy treatment

It is known that allergic reaction occurs when the immune system begins to perceive animal hair, plant pollen or dust as foreign agents. As a result of this process, the organism itself suffers from its own defense system, the cells of which are gradually destroyed. If you do not consult a doctor in a timely manner and do not begin to fight allergies, the immune system will weaken so much that it will begin to miss other "blows" from bacteria and viruses. Good health to you!

How well the immune system works will determine how resistant the body will be to attacks by viruses and bacteria. And the strength of immunity directly depends on your lifestyle. What exactly kills the immune system?

Constant sleep deprivation

You probably noted that most often colds and viruses overtake you precisely during the period when you do not sleep your prescribed 8 hours a day. This is also confirmed by studies - the results have shown that people who get enough sleep get the flu much less often. The fact is that lack of sleep provokes a jump in the level of the stress hormone, which in itself can provoke inflammation in the body.

Sedentary lifestyle

Try to exercise every day, or at least walk for about 30 minutes a day. This will support your immunity, every minute rejecting the attacks of microbes and viruses. Loads stimulate the production of hormones of joy, speed up the metabolism and develop the respiratory organs, due to it the body's defenses are strengthened.

Excess sugar

Eating too much sugar (in food or drink) interferes with immune cells. The negative effect persists for about two hours after you, for example, drank sweet soda. Instead of desserts, eat more fruits and vegetables. They are rich in useful micro and macro elements, and also contain vitamins A, C, E and others necessary for the immune system. The most beneficial fruits for the body's defenses are berries, citrus fruits, kiwi, apples, red grapes, cabbage, garlic, onions, spinach, sweet potatoes, and carrots.

chronic stress

Stress is part of our daily life. But if the influence of stress drags on for a long time, it makes the body more vulnerable to diseases, in particular, colds, the development of pathologies of organs and systems, as well as exacerbation of chronic diseases. Chronic stress affects the body high level the stress hormone adrenaline and cortisol, which suppress the immune system. It is impossible to avoid stress, but it is quite possible to manage your condition under stress. Meditation, yoga, breathing exercises, communication with friends or a psychotherapist, etc. will help with this.

Closure

Openness and the presence of pleasant and regular communication in your life has a positive effect not only on mood, but also on immunity. Research shows that social active people have stronger immunity than those who lead a secluded lifestyle. In particular, the immunity of sociable patients is formed faster and stronger even in response to a flu shot.

Lack of sense of humor

Laughter prolongs life - everyone has heard about it. And it's not just words. It actually keeps the levels of stress hormones in your body down and boosts the levels of cells in your blood that are responsible for fighting infection. To make yourself smile, watch funny videos on the Internet, comedy, look at funny photos, etc. Even the very anticipation of an upcoming fun event will positively affect your immunity.

Autoimmune diseases are diseases characterized by a malfunction of the immune system, due to which it begins to attack healthy tissues of the body. The symptoms of autoimmune diseases can be very different, depending on the type of disease.

Even healthy tissue cells can have antigens.

Normally, the immune system reacts only to antigens of foreign or dangerous substances, however, as a result of some disorders, it can begin to produce antibodies to cells of normal tissues - autoantibodies.

An autoimmune reaction can lead to inflammation and tissue damage. Sometimes, however, autoantibodies are produced in such small quantities that autoimmune diseases do not develop.

Expert opinion

Doctors still don't fully understand how the immune system works... and what happens when it starts working against us.

Currently, at least 80 autoimmune diseases are known - including lupus, multiple sclerosis, diabetes mellitus Type 1 and celiac disease - but there are at least 40 or more other diseases associated with malfunctioning of the immune system.

In the immune system, there are mechanisms that prevent the emergence of an immune response to its own normal antigens. But there is always the possibility that these mechanisms can break down, and the older the individual, the higher the likelihood of any failure. When this happens, autoantibodies are formed (antibodies that can interact with "their" antigens).

Unfortunately, there is little that doctors can do to help, other than to eliminate symptoms and help patients identify risk factors and avoid potentially life-threatening situations in the future.

What do we know

Pollution environment is also a risk factor for those who are genetically predisposed to autoimmune disease.

Secondhand smoke, chemicals in food or air, jet fuel fumes, exposure to UV rays, and other forms of environmental pollution are triggers for autoimmune disease.

Vaccines, all vaccines, have an immunosuppressive effect, i. suppress immune function. Chemical substances contained in vaccines depress the immune system; the virus contained in them depresses the immune system, and foreign DNA / RNA from animal tissues depresses the immune system.

Wheat germ agglutinin (WGA) causes thymus atrophy in rats and can directly bind to and activate leukocytes. Anti-WGA antibodies in human serum cross-react with other proteins, indicating that they may contribute to the development of autoimmune diseases.

All body systems depend on enzymes. Changes in enzymes caused by fluoride can damage the immune system.

Deformed enzymes (restructured) are proteins, but now they have become foreign proteins (antigens) that we know cause autoimmune diseases, including lupus, arthritis, asthma, and atherosclerosis.

Some nanoparticles have been linked to autoimmune diseases such as systemic lupus erythematosus, scleroderma, and rheumatoid arthritis.

Some autoimmune diseases

autoimmune disease	Tissues to which autoantibodies are produced	Consequences
Autoimmune hemolytic anemia	red blood cells	Anemia (decrease in the level of red blood cells in the blood), increased fatigue, lethargy, dizziness. Possible enlargement of the spleen. Anemia can occur in very severe forms and sometimes leads to the death of the patient.
bullous pemphigoid		Large blisters surrounded by reddened, inflamed areas of the skin; skin itching. At proper treatment the prognosis is favorable.
Goodpasture's syndrome	Lungs and kidneys	Symptoms of the disease: shortness of breath, expectoration of sputum with blood, weakness, swelling and itching. The prognosis is good if treatment is started before serious damage to the lungs and kidneys has occurred.
Graves' disease	Thyroid	Enlargement and overstimulation of the thyroid gland, which can lead to elevated levels of thyroid hormones (hyperthyroidism). Among the symptoms of the disease: intolerance high temperatures, tremor, weight loss, nervousness. Favorable prognosis with proper treatment.
Hashimoto's disease	Thyroid	Inflammation and damage to the thyroid gland, resulting in low levels of thyroid hormones (hypothyroidism). Symptoms include: weight gain, rough skin, cold intolerance, drowsiness. Lifelong treatment is often required to alleviate the patient's condition.
Multiple sclerosis	Brain and spinal cord	Damage to the sheath of affected nerve cells. As a result, the cells cannot transmit signals normally. Symptoms of the disease: weakness, unusual sensations, visual disturbances, dizziness, muscle spasms. Symptoms may disappear and return from time to time.
myasthenia gravis	Neuromuscular connections	Muscles, especially the eyes, weaken and tire quickly; the intensity of symptoms, as well as the progression of the disease, varies significantly in different patients. Symptoms can be controlled with specific medications
Pemphigus		The appearance of large blisters on the skin. The breach can be life threatening.
pernicious anemia	Cells of the inner lining of the stomach wall	The damage to the lining cells of the stomach that is characteristic of this autoimmune disorder makes it difficult to absorb vitamin B12, which is necessary for the maturation of blood cells and the maintenance of nerve cells. This results in anemia, as well as weakness and loss of sensation caused by damage to the nerve tissue. Left untreated, the disorder can lead to spinal cord injury; increased risk of developing stomach cancer. With timely treatment, however, the prognosis is favorable.
Rheumatoid arthritis	Joints and other tissues, such as lung, nerve, skin, and heart tissue	Rheumatoid arthritis can cause a variety of symptoms, including fever, weakness, joint pain , joint numbness and/or deformity, loss of sensation, chest pain , swelling.
Lupus	Joints, kidneys, skin, lungs, heart, brain and blood cells	The disease causes symptoms such as fatigue, shortness of breath, itching, heart pain, rash. Most patients with this disorder continue an active life despite occasional exacerbations.
Type 1 diabetes	Pancreatic beta cells (which produce insulin)	Symptoms include extreme thirst, frequent urination, increased appetite, and various long-term complications. Lifelong insulin treatment is necessary to control the patient's condition.
Vasculitis	Blood vessels	Vasculitis can affect blood vessels in one or more parts of the body. The prognosis depends on the type of vasculitis and the extent of tissue damage it has caused.

Autoimmune reactions can be triggered in several ways:

• A substance that is normally present only in a certain part of the body enters the bloodstream. For example, a blow to the eye can cause intraocular fluid to enter the bloodstream; the immune system recognizes the intraocular fluid as foreign and attacks it.
• Substances that are normal for the body are altered, for example by viruses, drugs, sunlight or radiation. These altered substances can be mistaken for foreign substances by the immune system.
• Foreign substances that are very similar to the natural substances of the body penetrate into the body. The immune system can mistakenly attack not only the first, but also the second. For example, the antigens of the bacteria that cause strep throat are similar to the cells in heart tissue. In rare cases, as a result of acute pharyngitis, the immune system begins to attack the heart of a person (this reaction develops with rheumatic fever).
• Cells that control antibody production - such as B-lymphocytes (a type of white blood cell) - may not function properly and produce abnormal antibodies against healthy cells in the body.
• The predisposition to develop autoimmune diseases can be inherited. In people who have this predisposition, any virus can cause this disorder. Hormonal factors can also influence the development of this type of disease - it is no coincidence that autoimmune disorders are most common in women.