Human Immune System - Organs Of The Immune System

2024 Author: Josephine Shorter | [email protected]. Last modified: 2024-01-07 17:49

The immune system

Human immune system organs

What is the immune system?

The immune system is a collection of organs, tissues and cells whose work is aimed directly at protecting the body from various diseases and at eliminating foreign substances that have already entered the body.

It is this system that is an obstacle to infectious agents (bacterial, viral, fungal). When the immune system fails, the likelihood of developing infections increases, this also leads to the emergence of autoimmune diseases, including multiple sclerosis.

Content:

1. Human immune system organs
2. The role of the human immune system
3. History of immunity research
4. How the immune system works
5. Allergic reactions
6. Does "super immunity" exist?
7. Factors that weaken our immunity
8. Useless methods of increasing immunity
9. Methods that have a real effect on immunity
10. But why then are many people tired and pale?

Human immune system organs

Organs that are part of the human immune system: lymph glands (nodes), tonsils, thymus gland (thymus), bone marrow, spleen and intestinal lymphoid formations (Peyer's patches). They are united by a complex circulation system, which consists of ducts that connect the lymph nodes.

The lymph node is an oval-shaped formation of soft tissues, 0.2 - 1.0 cm in size and contains a large number of lymphocytes.

The tonsils are small clusters of lymphoid tissue located on either side of the pharynx.

The spleen is an organ that looks very much like a large lymph node. The functions of the spleen are diverse: it is a filter for blood, and a storage for its cells, and a place for the production of lymphocytes. It is in the spleen that old and defective blood cells are destroyed. This organ of the immune system is located in the abdomen under the left hypochondrium near the stomach.

The thymus gland (thymus) is located behind the breastbone. Lymphoid cells in the thymus multiply and “learn”. In children and young people, the thymus is active, the older the person, the more passive and smaller this organ becomes.

Bone marrow is a soft, spongy tissue located within tubular and flat bones. The main task of the bone marrow is the production of blood cells: leukocytes, erythrocytes, platelets.

Peyer's patches are concentrations of lymphoid tissue in the intestinal wall, more specifically, in the appendix (appendix). However, the main role is played by the circulatory system, which consists of ducts that connect lymph nodes and transport lymph.

Lymphatic fluid (lymph) is a colorless fluid that flows through the lymphatic vessels and contains many lymphocytes - white blood cells that are involved in protecting the body from disease.

Lymphocytes are, figuratively speaking, the "soldiers" of the immune system, they are responsible for the destruction of foreign organisms or their own diseased cells (infected, tumor, etc.). The most important types of lymphocytes are B-lymphocytes and T-lymphocytes. They work together with the rest of the immune cells and do not allow foreign substances (infectious agents, foreign proteins, etc.) to invade the body. At the first stage of development of the human immune system, the body "teaches" T-lymphocytes to distinguish foreign proteins from normal (own) body proteins. This learning process takes place in the thymus gland (thymus) in early childhood, as the thymus is most active at this age. When a child reaches puberty, his thymus becomes smaller and less active.

An interesting fact: in many autoimmune diseases, for example, in multiple sclerosis, the patient's immune system “does not recognize” the healthy tissues of his own body, treats them like foreign cells, begins to attack and destroy them.

The role of the human immune system

The immune system emerged along with multicellular organisms and developed as an aid to their survival. It brings together organs and tissues that guarantee the body's defense against genetically foreign cells and substances from the environment. In terms of organization and functioning mechanisms, immunity is similar to the nervous system.

Both of these systems are represented by central and peripheral organs capable of responding to different signals, have a large number of receptor structures and specific memory.

The central organs of the immune system include the red bone marrow, thymus, and peripheral ones - lymph nodes, spleen, tonsils, appendix.

Leukocytes are the leading cells of the immune system. With their help, the body is able to provide various forms of an immune response upon contact with foreign bodies, for example, the formation of specific antibodies.

History of immunity research

The very concept of "immunity" was introduced into modern science by the Russian scientist I. I. Mechnikov and the German physician P. Ehrlich, who studied the body's defenses in the fight against various diseases, primarily infectious. Their joint work in this area was even awarded the Nobel Prize in 1908. A great contribution to the science of immunology was also made by the work of the French scientist Louis Pasteur, who developed a method of vaccination against a number of dangerous infections.

The word "immunity" comes from the Latin "immunis", which means "clean from anything." It was originally believed that the immune system protects us only from infectious diseases. However, the studies of the English scientist P. Medawar in the middle of the twentieth century proved that immunity provides protection in general from any foreign and harmful interference in the human body.

Currently, immunity is understood, firstly, resistance to infections, and secondly, the response of the body, aimed at destroying and removing from it all that is alien and threatening to it. It is clear that if people did not have immunity, they simply would not be able to exist, and it is its presence that makes it possible to successfully fight diseases and live to old age.

How the immune system works

The immune system has been formed over the long years of human evolution and acts like a well-oiled mechanism. It helps us fight disease and the harmful effects of the environment. The tasks of immunity include recognizing, destroying and bringing out both foreign agents that penetrate from the outside, and decay products formed in the body itself (during infectious and inflammatory processes), as well as exterminate pathologically changed cells.

The immune system is able to recognize many "outsiders". Among them are viruses, bacteria, toxic substances of plant or animal origin, protozoa, fungi, allergens. Among the enemies, she also considers her own cells that have turned into cancerous, and therefore become dangerous. The main goal of immunity is to provide protection against intrusions and preserve the integrity of the internal environment of the body, its biological individuality.

How is the recognition of "outsiders" carried out? This process takes place at the genetic level. The fact is that each cell carries its own genetic information inherent only in this particular organism (you can call it a label). It is her immune system that analyzes when it detects penetration into the body or changes in it. If the information matches (the tag is available), it means that it is your own, if it does not match (the tag is absent), then it is someone else's.

In immunology, foreign agents are commonly called antigens. When the immune system detects them, defense mechanisms are immediately activated, and a fight begins against the "outsider". Moreover, to destroy each specific antigen, the body produces specific cells, they are called antibodies. They approach antigens like a key to a lock. Antibodies bind to the antigen and eliminate it, so the body fights the disease.

Allergic reactions

One of the main immune responses of a person is allergy - a state of increased body response to allergens. Allergens are substances that contribute to the occurrence of a corresponding reaction. There are internal and external allergy provocateurs.

External allergens include certain foods (eggs, chocolate, citrus fruits), various chemicals (perfumes, deodorants), and medicines.

Internal allergens are own cells, usually with altered properties. For example, with burns, the body perceives dead tissue as foreign and creates antibodies for them. The same reactions can occur with stings of bees, bumblebees and other insects.

Allergy develops rapidly or consistently. When an allergen acts on the body for the first time, the immune system produces and accumulates antibodies with increased sensitivity to it. When the same allergen enters the body again, an allergic reaction occurs, for example, skin rashes, swelling, redness and itching appear.

Does "super immunity" exist?

There are people who convince that there is super immunity, and this phenomenon is not so rare. But they cannot give an answer to the question that arises: why has not nature created a superpowerful system, which would not be affected by any pathogenic microorganism, in a natural way. In fact, the answer is obvious: extra strong immunity will become a threat to the human body. Any distortion of this complex multicomponent living system threatens to disrupt the functioning of vital organs. Here are just a few examples:

1. An allergic reaction is a consequence of a particularly active immune system to proteins that are absolutely common for others. The result is allergic asthma or eczema.
2. The "cytokine cascade" is a potentially lethal reaction. Its inflammatory reaction is so powerful that the mass of cytokines produced uncontrollably by the body leads to the development of multiple organ failure, as a result of which the patient can die. Hypercytokinemia is one of the causes of death during an influenza pandemic.
3. An autoimmune disease occurs when overactive cells of the immune system are toxic to their own body. Example: type 1 diabetes mellitus, several types of rheumatoid arthritis, etc.

Which of the following is meant by those who advocate "strengthening immunity"? These examples prove that raising the level of sensitivity of the immune system, or increasing the amount of substances it produces in special cases, as well as an increase in the number of cells - all this causes enormous harm to the body.

It should be noted that when the immune system comes into contact with an external attack and reacts with an increase in its cellular balance, then, as “victory” comes, the body is diligently cleared of excess “ballast” of protective cells - they collapse in the process of programmed destruction - apoptosis.

Therefore, scientists have no arguments for the existence of a hyper-strong immune system. If we consider immunity, it becomes clear that “norm” and “pathology” are precisely those concepts that you cannot argue with. And the meaning of the expressions: "strengthen immunity", "strengthen it", "improve the state of the immune system" - have no basis and are the result of quality advertising.

Factors that weaken our immunity

At birth, nature “gives” a person an almost ideal and most effective defense system. It is so perfect that you have to try hard to "weaken" it. So, as a result of which there is a real deterioration in the work of this defense mechanism, or a decrease in immunity?

• Prolonged severe stress (for example, the sudden loss of a loved one, the threat of an incurable disease, war), hunger and food shortages, Stable lack of intake of important microelements and vitamins by the body. If these conditions are observed for months, or even years, then they really affect the decrease in the protective segments of the immune system.
• Some chronic diseases influence the undermining of the protective function. This includes diabetes mellitus.
• Congenital and acquired immunodeficiencies (AIDS), as well as procedures that deliberately suppress the immune system: chemotherapy, immunosuppressive therapy.
• Advanced age. Elderly people experience a drop in the work of all systems, including the immune system. For example, the number of T-lymphocytes produced in response to an infection in the body decreases markedly over the years. As a result, disease resistance decreases.

It should be noted that "traditional" infections - flu, colds and others - are not scary for the immune system. The painful conditions that people experience when they get the flu from time to time are just part of the immune system's response. This is not her downfall.

Useless methods of increasing immunity

Taking immunostimulants

Any immunostimulants are useless for an ordinary person who overcomes the most serious diseases that destroy the immune system. It is already known from the above that the immunity of a patient, whose state belongs to the average statistical, does not need additional stimulation.

In fact, pharmaceutical companies have proven drugs that work to boost the immune system (immunostimulants) or weaken it (immunosuppressants). But doctors still prescribe drugs to patients in the complex therapy of especially serious diseases. Taking such powerful drugs by an ordinary person during a banal cold is not that unnecessary, but even dangerous.

Another point, called "immunostimulants", in pharmacies very often offer drugs with unconfirmed effectiveness. And their harmlessness, the absence of side effects, which the advertisement tells so vividly, confirms that, in fact, this is a placebo, and not real medicines.

Immunologist Elena Milovidova:

People are already accustomed to attributing various ailments to "reduced immunity" and seek to buy stimulants, using them at their own discretion. They do not want to hear the opinion of experts that problems with the body's immune response arise in unique cases: after taking aggressive antibiotics, after surgery, implantation, and others.

Today, all kinds of drugs based on interferons, components that affect immune metabolism, are in demand. But almost all immunologists believe that immunostimulants are either completely useless, or more serious drugs should be used. This refers to the need for their introduction into the course of treatment for patients with a specific diagnosis, for example, with secondary immunodeficiency. The rest of the stimulation is harmful - it leads to exhaustion. If you constantly stimulate the production of leukocytes with drugs, the immune system will begin to lose its direct function. If you feed the body with various stimulants on a constant basis, then it will become a "beggar", constantly begging for alms. That's when the time comes for the onset of serious problems with immunity.

If you intend to tone up, cheer up, then you should pay attention to natural adaptogens: Chinese lemongrass, ginseng, eleutherococcus, pink radiola. They act as amplifiers of RNA and protein synthesis (the basis of human cells), activate metabolic enzymes and the work of the endocrine and vegetative systems, without affecting the immune system at all.

A lot of vitamins

Vitamins are a group of components to which the glory of substances that have a positive effect on the immune system is artificially attached. The exception is vitamin D. It really has a direct relationship to this process - it activates inactive immune cells T-lymphocytes and promotes their transformation into T-killers. They take part in the destruction of negative pathogenic microorganisms.

All other groups of vitamins are not directly involved in the functioning of the immune system. They, of course, make people healthier and this is excellent, but they do not play any role in increasing immunity. Note that the vaunted anti-cold effect of vitamin C has not been confirmed in clinical trials.

Bath

The statement of the positive effect of a sauna or a bath on the immune system also has no basis. As for the cardiovascular system, it definitely affects, and very often negatively. Therefore, before visiting the bath, get an assessment of your health, and do not focus on colds or flu.

Folk remedies

We all often hear garlic boosts immunity. There is no scientific confirmation of this - garlic does not affect the immune system, it only releases phytoncides - plant compounds that have a mild bactericidal effect that passes quickly.

An equally popularized product is bee honey. Same effect as garlic: slight bactericidal effect. Although there is a tonic and general strengthening effect, honey has no effect on immunity.

Methods that have a real effect on immunity

It can be summed up that when it comes to immunity, first of all, it means the body's ability to independently eradicate destructive influences from the outside. The healthier the body, the better the immune system functions. The level of health is in our hands.

Regular vaccination

Why is vaccination ranked first? Because vaccination is the surest way to improve the immune system.

The body, under the threat of possible dangers in the form of various infections, begins to respond correctly and quickly to them.

Any vaccination raises the level of speed and quality of response to a specific infection. The natural process of forming immunity loses to the advantages of vaccines. Studies have shown that even the immune system of elderly people is strengthened, their chances of suffering the flu without loss increase significantly.

Balanced diet

What is characteristic is that weight deficiency and excess weight equally weaken the body. Do not forget that the immune system tends to work normally as a complex. Even minor deviations from the norm lead to disturbances in the functioning of all body systems, including the immune system. It is impossible to "improve" immunity without removing the root cause of the problem.

Read more: Diet ATS - a diet that covers all the needs of the body

Regular physical activity

In order to preserve a healthy heart and blood vessels until old age, to keep blood pressure and body weight normal, constant attention must be paid to physical activity. A healthy, physically developed person has an immune system that works quickly and efficiently in response to all threats.

Rejection of bad habits

The immune system has several layers of defense. These include all mucous membranes. Smoking negatively affects the mucous membranes of the respiratory tract. This becomes the reason for the shutdown of protective mechanisms and a decrease in the level of resistance to various types of infections.

Alcohol suppresses the formation of T-lymphocytes, negatively affects leukocytes. This leads to a deterioration in the ability to fight pathogenic bacteria, plus - the production of cytokines is disrupted.

But why then are many people tired and pale?

Professor Yuri Smolkin:

This factor characterizes as follows. He considers the cause of lethargy, pallor, weakness, frequent colds, a focus of "healed" infection or latent allergies.

Studies have shown that in 50% of cases, chronic fatigue syndrome is triggered by viruses from the herpes group (including the Epstein-Barr virus). This leads to a significant "drop in immunity". You can find out the exact cause of the infection by passing a complete blood count + analysis for viruses. After that, the doctor selects a set of tools for effective treatment of the patient, including:

• Antiviral drugs.
• Multivitamins.
• Sedatives to normalize the emotional background.

[Video] Dr. Berg - How to strengthen the immune system and not get sick?

Article author: Mochalov Pavel Alexandrovich | d. m. n. therapist

Education: Moscow Medical Institute. IM Sechenov, specialty - "General Medicine" in 1991, in 1993 "Occupational Diseases", in 1996 "Therapy".