When a foreign object appears in the body, immunity becomes to protect human health. The risk of infection with infectious diseases depends on how developed it is. Thus, immunity is the body’s ability to resist foreign invasions.
The immune system is in close interaction with other systems in the human body. Therefore, for example, the nervous or endocrine diseases he has will significantly reduce immunity, and low immunity, in turn, can endanger the entire body.
The described body defense is divided into two types: innate and acquired immunity . Next, we will talk more about their features and methods of action.
Inborn body defense
Each person is born with its protective functions, which make up the immune system. Congenital immunity is inherited and accompanies a person all his life.
At birth, a child from a sterile mother’s womb enters a new world for him, where he is immediately attacked by new and completely unfriendly microorganisms that can seriously harm the baby’s health. But he does not get sick right away. This is precisely what happens because in the fight against such microorganisms, the body of the newborn is helped by natural innate immunity.
Each organism is fighting on its own for internal security. The system of innate immunity is quite strong, but it directly depends on the heredity of a particular person.
The formation of body protection
Congenital immunity begins to form when the baby is in the womb. From the second month of pregnancy, particles are laid that will be responsible for the safety of the baby. They are produced from stem cells, then enter the spleen. These are phagocytes - cells of innate immunity . They work individually and do not have clones. Their main function is the search for hostile objects in the body (antigens) and their neutralization.
The named process occurs using certain mechanisms of phagocytosis:
- The phagocyte moves to the antigen.
- Attaches to it.
- The phagocyte membrane is activated.
- The particle is either drawn into the cell, and the edges of the membrane are closed above it, or lies in the formed pseudopodia enveloping it.
- Lacosomes containing digestive enzymes enter a vacuole with a foreign particle enclosed in it.
- The antigen is destroyed and digested.
- Degradation products are thrown out of the cell.
There are also cytokines in the body - signaling molecules. When dangerous objects are detected, they cause phagocytes. Using cytokines, phagocytes can call other phagocyte cells to the antigen to help and activate dormant lymphocytes.
Defense in action
In the degree of resistance of the body to infections, immunity plays an important role. In such cases, innate immunity provides body protection by 60%. This occurs using the following mechanisms:
- the presence in the body of natural barriers: mucous membranes, skin, sebaceous glands, etc .;
- liver work;
- the functioning of the so-called complement system, consisting of 20 proteins synthesized by the liver;
- phagocytosis;
- interferon, NK cells, NKT cells;
- anti-inflammatory cytokines;
- natural antibodies;
- antimicrobial peptides.
The inherited ability to destroy foreign substances, as a rule, acts as the first line of defense of human health. The mechanisms of innate immunity have such a feature as the presence of effects that quickly provide for the destruction of the pathogen, without preparatory steps. The mucous membranes secrete mucus, which complicates the possible attachment of microorganisms, and the movement of the cilia clears the respiratory tract from foreign particles.
Innate immunity does not change; it is controlled by genes and inherited. NK cells (the so-called natural killers) of innate defense kill the pathogens that are formed in the body - these can be virus carriers or tumor cells. If the number and activity of NK cells decreases, the disease begins to progress.
Acquired immunity
If innate immunity is present in a person from birth, then acquired appears in the process of life. It is of two types:
- Naturally obtained - formed in the process of life as a reaction to antigens and pathogens entering the body.
- Artificially acquired - formed as a result of vaccination.
The antigen is administered by the vaccine, and the body responds to its presence. Recognizing the "enemy", the body produces antibodies to eliminate it. In addition, for a while, this antigen remains in cellular memory, and in the event of a new invasion it will also be destroyed.
Thus, an “immunological memory” exists in the body. Acquired immunity can be "sterile", that is, it can be preserved for life, but in most cases it exists as long as there is a harmful pathogen in the body.
Principles of protection of congenital and acquired immunity
The protection principles have one direction - the destruction of malicious objects. But at the same time, innate immunity fights dangerous particles with the help of inflammation and phagocytosis, and the acquired one uses antibodies and immune lymphocytes.
These two defenses work interconnected. The compliment system is an intermediary between them, with its help the continuity of the immune response is ensured. So, NK cells are a part of innate immunity, while they produce cytokines, which, in turn, regulate the function of T-lymphocytes related to acquired.
Enhancing Protective Properties
Acquired immunity, innate immunity - all this is a single interconnected system, which means that a comprehensive approach is needed to strengthen it. It is necessary to take care of the body as a whole, this contributes to:
- sufficient physical activity;
- proper nutrition;
- favorable environment;
- intake of vitamins;
- frequent airing of the room and maintaining a favorable temperature and humidity in it.
Nutrition also plays an important role in the effectiveness of the immune system. For it to work clearly, the following must be present in the diet:
- meat;
- fish;
- vegetables and fruits;
- seafood;
- dairy products;
- green tea;
- nuts
- cereals;
- legumes.
Conclusion
From the foregoing, it is clear that for normal human life a well-developed immunity is necessary. Inborn immunity and acquired immunity act interconnectedly and help the body get rid of harmful particles that have penetrated into it. And for their quality work, it is necessary to abandon bad habits and adhere to a healthy lifestyle, so as not to disrupt the vital activity of “useful” cells.