Vladimir Yashin - about breakthrough discoveries in the field of immunology

At the start of this fall, world medicine has come very close to a milestone beyond which a truly fantastic prospect opens up: getting rid of a whole bunch of currently incurable diseases, some types of cancer in the first place, is becoming real. This perspective has been brought to light by a number of discoveries in the field of immunology. And the key among them: doctors have discovered the ability of a person to independently “improve” his defense system. Simply put, it becomes possible to “train” our body to fight the most dangerous diseases. "Ogonyok" understood the details

Problems with immunity are the flip side of modern civilization: you often have to pay for the ostentatious quality of life and comfort with your health
Photo: Reuters

Vladimir Yashin, doctor

Why does the human immune system, designed to protect us from pathogenic microbes, viruses, and foreign proteins, remain inactive in the face of a malignant tumor? The question has been worrying oncologists, immunologists, and biologists around the world for decades. Agree: if doctors managed to “train” the immune system to fight cancer cells, we could seriously talk about a new stage in the treatment of oncology. Recently, several institutes in different countries have been working on this problem, despite the fact that most of the scientific community was skeptical about this work and, as it turned out, in vain. Two years ago, an international team of scientists led by Professor Daniel Chen announced that they had managed to understand why the immune system does not respond to the tumor and does not destroy it. And in August of this year, it became known that clinical trials had begun on a substance that could seriously boost the immune system, forcing it to destroy cancer cells.

“We can say that until now there has been more noise in the work of oncoimmunologists than specifics,” Professor Chen himself admits, “but now we can combine the knowledge gained for a specific result.”

To reach this discovery, scientists had to look deep into the processes inside our body. We are talking, in particular, about the work of T-lymphocytes - immune cells, an important part of the most complex defensive system that guards health. It turned out that when a T-lymphocyte, which must recognize and destroy it, approaches a cancer cell, it releases a special protein PDL-I onto its surface. And he, sensing a threat, promptly blocks the receptors - sensitive nerve endings - of T-lymphocytes. As a result, the immune cell loses not only the ability to recognize the tumor, but also its damaging activity. According to Professor Chen, it looks as if the cancer cell puts its hands forward, stops the immune cell and it “falls into complete prostration.”

Based on this discovery, American scientists have developed a drug codenamed anti-PDL-I, which interferes with the activity of the tumor protein and activates blocked immunity. Clinical trials of the new drug have shown high effectiveness in the fight against certain types of cancer. Now scientists are going to officially register their drug as quickly as possible, as well as continue scientific research with the aim of developing new drugs against cancer. As emphasized by the head of the laboratory of epigenetics at the Institute of General Genetics. N.I.Vavilov RAS Professor Sergei Kiselev, the main difficulty of the work is that a malignant tumor is initially born from the body’s own cells and therefore the immune response to it is very weak.

“If a microorganism or a virus that penetrates us causes our temperature to rise and an inflammatory reaction begins, then the tumor develops imperceptibly and accustoms the body to the fact that it is our own, although it is foreign,” explains Professor Kiselev. “That’s why it was so important to find specific antitumor antigens that distinguish it from the norm, and make an antitumor vaccine.

Train a cell

The work on “modernizing” T-lymphocytes, despite its revolutionary nature, has become to some extent logical. The fact is that immunology has developed particularly rapidly in recent decades: it has given the world as many as 16 Nobel laureates - a complete record among all other disciplines in the field of medicine and physiology. And this interest continues unabated: in 1901, the very first Nobel Prize was awarded to Emil Adolf von Behring for the discovery of antibodies, and more recently, immunologists Bruce Beutler, Jules Hoffman and Ralph Steinman received the prize for being able to show how different types of immunity are activated - congenital and acquired. Innate, let me remind you, is an ancient evolutionary acquisition - all multicellular organisms have a similar defense mechanism. This is a kind of collective memory of the body’s ancestors about which violators require an immediate response; this memory is fixed at the gene level.

Another type of immune system is adaptive. This is a new system from an evolutionary point of view; it is found only in vertebrates. The work of this type of immunity is associated with the production of antibodies and T-lymphocytes. This system does not tell us whether we are a friend or an enemy, but very sensitively determines how different foreign molecules are from the molecular structures of our body. It is adaptive immunity, according to experts, that can be trained and taught.

Working in this direction, Ralph Steinman proved that the complex immune system has a kind of conductor - special dendritic cells, a kind of intermediary between the two types of immunity. They constantly monitor the situation for strangers and, if something happens, trigger the body’s immune response. It was thanks to the work of immunologists at the turn of the 20th and 21st centuries that it became possible today to develop new ways to treat infectious and oncological diseases.

Thus, in 2010, for the first time, the FDA (United States Food and Drug Administration) approved an antitumor vaccine based on dendritic cells for prostate cancer. Dendritic cells were not chosen by chance: they are the ones who detect foreign proteins and “show” them to T-lymphocytes. After such a “training course,” T-lymphocytes enter the fight. It turned out that dendritic cells themselves learn well. To create a vaccine, scientists extract dendritic cells from the patient’s blood and mix them with protein fragments of cancer cells, after which the cells, already “trained” to recognize the “enemy,” are sent to “train” T-lymphocytes. At the Research Institute of Clinical Immunology of the SB RAS, where a similar vaccine is being developed for the treatment of breast cancer, they emphasize that their task is not prevention, but treatment by activating the immune system.

One of these vaccines was created at the Oncology Research Institute named after. N.N. Petrova in St. Petersburg and is already used for the treatment of melanoma and soft tissue sarcoma. As Professor Liping Chen from Yale Oncology University (USA) emphasizes, the treatment strategy for oncology will soon be seriously revised: thanks to the progress of immunotherapy, chemotherapy will fade into the background.

Lines of defense

The human immune system is a complex mechanism that involves several organs. The central glands are the thymus gland, located at the base of the neck, and the bone marrow. They produce lymphocytes (in the thymus - T-lymphocytes, in the bone marrow - B-lymphocytes), which protect us from the attacks of a hostile microcosm.

Its other important organs are the lymph nodes and the spleen. It is in these “divisions” of the immune system that the main weapon is produced - special immunoglobulin proteins called antibodies. They have the amazing property of connecting with the microbe in response to which they were created. Just as a key fits only one lock, so each antibody reacts to its own antigen (foreign substance) that has entered or is about to enter the body. The intestines, tonsils and adenoids are also part of the immune system. Well, its activity is regulated by the central nervous and endocrine systems.

The first “defensive line” in the path of microbes and viruses is the skin and mucous membranes. Then mobile cells - phagocytes - constantly move through the blood and lymphatic vessels (they are produced in bone marrow stem cells) enter the battle. Moreover, if the number of the “enemy” is large, the number of defenders also grows quickly. Then T-lymphocytes are included in the fight, capable of not only distinguishing individual microbes, but also remembering them, and also determining whether the body has encountered them before or not. As a result, these cells begin to help B lymphocytes increase the synthesis of antibodies, which determine the immune response to the re-introduction of the “stranger”. In this case, the pathological process in the body often simply does not occur, which, by the way, explains the existence of long-term immunity to a number of diseases, for example, measles or chickenpox.

This is how the immune system resists the aggression of many hostile microbes. But this mechanism is not very effective in the fight against viruses, because they manage to hide by infiltrating a healthy cell and forcing it to work for itself, that is, to produce new viruses. In this case, the immune system sends its “special service” against enemies - cells called “killers”. They are able to recognize virus-infected body cells and destroy them.

The immune system also has its own memory. Let's imagine that some microbe entered the body and caused a disease. In this case, the immune response was successful, and the lymphocytes remembered the pathogen. Consequently, if he attempts repeated aggression, he will be immediately recognized and destroyed. For example, in a child who falls ill with, say, an acute respiratory infection, immunological memory is usually formed within 18-40 days, that is, even after the disappearance of external signs of the disease.

However, for some children it takes longer. And it is possible that the causative agent of the same acute respiratory infection will again attack the body, and information about it will not yet have time to be fixed in the immunological memory. In this case, the defense system will not recognize it, and it will not be possible to avoid recurrent illness. Actually, this is what happens in frequently ill children. One of the reasons for such a slow immune response may be genetics. Other possible reasons include unfavorable ecology, poor living conditions, etc.

According to immunologists and pediatricians, immunity against diseases accumulates in a child only by the age of 12. And experts do not advise rushing its formation with the help of, for example, immunotropic drugs: these are potent drugs, the use of which can lead to serious consequences.

Mass hypnosis

Today it has been proven that immunity not only protects the body from pathogens of various diseases, but also controls the development of the embryo in the womb, determines the success or failure of organ and tissue transplant operations. In a word, its significance is extremely great and it is with it that humanity has had great problems in recent decades.

According to WHO forecasts, in the 21st century, diseases associated with chronic immune disorders will take first place. One of the reasons for this, WHO experts call the widespread and often unjustified use of antibiotics, which, while suppressing the growth of pathogens, also reduce the number of antigens that stimulate the immune system. Add the adverse effects of the environment, which contains a huge amount of substances that suppress the immune system. Russia, however, has its own specifics.

“In our country, the number of immunopathologies is growing every year,” says Natalya Starostina, a doctor at the Immunopathology Clinic of the Research Institute of Fundamental and Clinical Immunology. “And this is primarily due to the fact that people simply do not receive from food the basic set of nutrients that the body needs. If we look at the diet of pensioners, we will see that they eat meat once or twice a week (sausage and frankfurters do not count). The same with fruits and vegetables. Namely, retirement age, when the thymus fails - one of the main organs responsible for immunity, the most vulnerable.

As a result, today the number of cases of so-called acquired immunodeficiency, which most often develops after infectious diseases (for example, influenza) or against the background of prolonged stress, depression, and excessive fasting, is growing. In order for the immune system to work correctly, doctors first of all advise changing your lifestyle and adhering to the basic principles of a healthy and, most importantly, as varied diet as possible. However, in megacities, the simplest recommendations, alas, turn out to be the most difficult to implement.

Immunotherapy

Experience

In order for the immune system to function normally, it turns out that it must first be well fed. Here are the elements that will help you “tighten up” it on the eve of the winter season

Flavonoids

Plant substances that trigger the work of genes responsible for immunity. Rosehip is especially valuable; in addition to flavonoids, it contains organic acids, pectin, and most importantly, vitamins C, P, A, B2, K, E. The most important flavonoids are also found in tomatoes, sweet peppers, apples, citrus fruits, cranberries, and green tea . During the winter, at least one of the listed products should be in the diet every day.

Anthocyanins

A special type of flavonoid. Anthocyanins have a strong immunostimulating effect and can serve to prevent tumors. In addition, they have a bactericidal effect on putrefactive intestinal microflora, enhance the biological effect of vitamin C and have P-vitamin activity. They are found in dark vegetables and fruits. They are rich in beets, red cabbage, eggplants, dark grapes and red wine.

Squirrels

The diet must contain animal and plant proteins in sufficient quantities - the building material for the cells and tissues of the body. To do this, the menu should include meat, fish, milk, eggs, legumes, buckwheat and oatmeal, as well as more specific products - beef liver and seafood - shrimp, mussels, squid, which lay the foundation for new cells that guard our immunity .

Minerals

A number of substances have an immunostimulating effect - iron, copper, magnesium, zinc. Most of them are in offal - liver, kidneys, heart, as well as in nuts, legumes and chocolate. In general, people with weakened immune systems are recommended to take a course of additional vitamin therapy before the start of the cold season. To do this, it is better to use vitamin complexes rather than individual vitamins.

Adaptogens

This is the name of a whole class of substances that protect humans from the harmful effects of the environment. Penetrating inside the cell, they activate the restructuring of metabolism to work under stress, and the body begins to work in a more economical mode. They also promote the synthesis of endogenous biostimulants, such as interferon. Relict organisms that survived global cataclysms—ginseng, Eleutherococcus, aralia, Schisandra chinensis, as well as bees and snakes—have learned to produce biologically active substances with adaptogenic effects.

Probiotics

These are drugs containing strains of microorganisms that are necessary for our intestines (remember, it is an integral part of the immune system). According to research, probiotics can help those who suffer from irritable bowel syndrome, atopic dermatitis, diarrhea, allergic rhinitis and a number of other ailments, including colds. To increase their content, you need to increase the amount of fermented milk products in your diet.

Carotenoids (provitamin A)

These substances are considered antioxidants that help the body fight stress. Recently it has been found that they have an antitumor effect. Yellow-green and red vegetables (carrots, red peppers, onions, etc.) are especially rich in them. The carotenoids in them are particularly resistant to heat treatment and therefore hardly lose color.

Endorphins

Endorphins are also called pleasure hormones. But, as it turned out, in addition to a beneficial effect on mood, they have an anti-inflammatory effect and can activate the immune system. The easiest way to increase their level is through gentle exercise. Exhaustive training is of no use here.

Self defense without drugs