Strong immunity is a prerequisite for human health. This system performs protective functions, preventing third-party pathogens from developing in the body. There are several types of immunity. They are characterized by different mechanisms of formation and impact. Only the coordinated work of all protective systems can prevent the penetration of pathogens into the body. What constitutes adaptive immunity will be discussed in detail below.
general characteristics
Congenital and adaptive immunity are two components of the body's defense system. Together, they are a qualitative criterion that shows the ability to withstand various kinds of external influences and diseases. Today, for its assessment, such a concept as immune status is used.
Immunity allows you to maintain the integrity of the genetic information of the body throughout its life. It can be congenital and acquired. The first type of protective function is also called genetic, or primary. It is formed in the child in the womb. This is the foundation for the development of subsequent defense mechanisms. Congenital immunity depends on what ailments parents and other blood relatives hurt, how their body reacted to these pathologies.
Adaptive (acquired) immunity is formed throughout a person’s life. There are several varieties of this type of protection. Acquired immunity is formed under the influence of natural and artificial factors. In the first case, various diseases affect the body, against which certain forces are released. Protection information in this case is stored in the body. This is an active immunity.
The second type of protection is called passive or artificial. An injection with a small amount of the pathogen is injected into the body. As a result, the immune system fights the pathogen, and information about this process remains for a certain time or for a lifetime in the body.
Features of acquired immunity
Congenital and adaptive immunity in the body continuously. They perform the most important functions. Adaptive (specific) immunity is the second phase of the body's defensive reactions. Its characteristic feature is the fact that it is not inherited. It is formed throughout the life of a person.
The acquired type of body defense is more intense than the innate barrier from various foreign microorganisms. Since the body adapts to environmental conditions due to similar reactions, this type of immunity is called adaptive.
This type of protection is formed during infectious diseases, poisoning. However, it is not stable. Not all pathogens can be clearly remembered by the body. So, for example, a person who has had gonorrhea can get it again. The immunity that persists after this disease is weak and short-lived. Therefore, the probability of getting this disease is once again great.
However, some diseases, such as chickenpox, are transmitted only once by the body. A person can no longer get this disease. The immunity that is produced after this disease is stable. However, it is not inherited. In parents who have had chickenpox, a child can still become infected with this virus.
The more diverse the pathogens that enter the human body, the more different antibodies the body makes to fight them. This forms a defensive reaction. Therefore, children who grew up in sterile conditions are sick much more often than children who, at a young age, were in contact with various microbes and bacteria.
Main differences
To understand the features of different types of protective reactions of the body, it is necessary to consider in detail the comparative characteristics of innate and adaptive immunity. They differ in a number of indicators. Congenital immunity was the first defense system that formed in vertebrates during evolutionary development. Secondary (acquired) immunity appeared much later.
In the human body, innate immunity is the first to form. This is the basic foundation that he inherited from his parents. Based on this type of protection, a subsequent reaction of the body to the surrounding adverse factors is formed. This is a non-specific immunity that is transmitted from the mother’s body to the baby through the placenta and breast milk.
The acquired type of body defense makes up only 35-40% of the body's immune status. However, it is more intense. It faster and more actively affects pathogens of infection, other pathogens. Congenital immunity is less pronounced. It responds to the occurrence of the disease more slowly. In this case, the reaction that occurred to one or another alien body is not remembered.
Acquired immunity is characterized by the presence of a memorization process. For this reason, such a barrier is more intense and faster.
Mechanism of action
The mechanism of adaptive immunity is quite interesting. This is a complex system that continuously functions in the human body. When a virus, bacterium or other pathogenic microbe enters the body, the immunity must first recognize and identify it. This is necessary to be able to distinguish the necessary, "their" bacteria from foreign, destructive. Certain types of white blood cells are responsible for this function. They approach the bacteria and carry out the identification procedure.
Further, after collecting the necessary information, it is transferred to other cells. Depending on what type of foreign microorganisms you have to deal with, a method of suppressing the focus of infection is chosen. For viruses, bacteria, allergens, poisons, the body produces different types of white blood cells. They approach and absorb a foreign cell.
Information about which immune response was given in this case is stored in the memory of the body. There are special white blood cells that conduct training, transmit relevant information to new cells of the immune system that are just developing. This allows you to quickly respond to a pathology with its secondary appearance.
In this system, each cell of immunity has its own special role. They work as a single, harmonious system, complementing each other. In this case, the body's response to the causative agent of infection can be different. There are cellular and humoral adaptive immunity.
Types of Immunity
The acquired type of protection can be of two types. This is a cellular and humoral adaptive immunity. They perform different functions. Cellular protective factors act aggressively against foreign microorganisms. The cells that are produced by the body for this destroy tumor, diseased, foreign cells.
For this, a mechanism such as phagocytosis is launched. A cell approaches a foreign object and then swallows it. Then it is "digested", split in a special way. This function is performed by leukocytes. They belong to a specific group. Under the action of acquired immunity, T-lymphocytes are involved in the work.
An example of the effects of cellular adaptive immunity is the rejection of implants, transplanted organs and tissues. This type of protection protects the body from the development of tumors and infections. Lymphocytes that take part in the destruction of foreign objects are formed in the bone marrow. Then they move to the thymus, where they undergo a period of maturation and training. It is for this reason that they are called T-lymphocytes. They leave lymphoid organs many times. Then the cells come back. This allows you to quickly respond to the causative agent of infection.
Humoral adaptive immunity is provided by the production of antibodies. They provide protection. In this case, it is antibodies that are immune factors. B cells are involved in the production of these cells. Their work is an allergic reaction to certain medications, pollen and other components.
It is impossible to pinpoint the boundary between humoral and cellular immunity. They are closely connected and work together.
The main components and the formation of the immune system
Existing adaptive immunity factors consist of several key components. These include the functioning of the thymus, which produces T-lymphocytes, as well as the process of antibody formation. Also included are cytokine synthesis and transfer factor.
The main humoral factors of adaptive immunity include the work of the thymus. It is also called the thymus gland. This process can be compared with the formation of a graduated system. First, preschoolers are trained, then schoolchildren. After this comes the turn of higher education. The same thing happens with immunity cells.
In the thymus, lymphocytes receive a "preschool" and "primary secondary" education. These include T-suppressors, T-hellers, as well as cytotoxic type T-lymphocytes.
While a person is in childhood, their “training” is carried out less intensively. However, over time, the load increases. By the onset of puberty of the human body, the "training" of lymphocytes becomes the most intense. It stimulates the immune system. When a person becomes adults, the thymus gradually decreases in size. He begins to lose his activity.
Over time, it decreases in size. By old age, the production of T-lymphocytes is reduced. Their training is becoming less intense. Therefore, in old age there is a decrease in immunity.
Antibodies
In addition to cells of adaptive immunity, antibodies are also produced in the body. These are special protein molecules. They are synthesized by B-lymphocytes. This is the most active part of the immune system. There are antigens on foreign cells. Antibodies are connected with them. They have a certain shape. It corresponds to the configuration of the antigen. After antibodies combine with foreign cells, they neutralize them.
These cells are also called immunoglobulins. There are several classes of such proteins. The most important of them are LgM, LgG, LgA. Each of them performs special functions. By what immunoglobulins are found in the analysis, it is possible to determine how long a person became ill with a particular ailment. At an early stage, some types of immunoglobulins are produced, and at a later stage, others.
Macrophages
In addition to antibodies, macrophages also work with antigens. These are large cells of adaptive immunity, which destroy in parts large sections of infected, foreign or damaged (dead) tissue. They accompany regeneration processes. After a macrophage comes in contact with a malignant or infected cell, it destroys it, but not completely. Some parts of the cell remain. Specific antibodies are formed on these antigens.
Antigens store information about a foreign cell. They transmit this information in the formation of other components of the immune system. After this, T-lymphocytes can easily recognize a foreign antigen. The immunity is triggered in this case promptly. Cancerous and infected cells are selectively destroyed. Specific memory cells are also responsible for this.
It is the preservation of information that helps adaptive immunity persist throughout life. T and B cells in memory store information about many pathologies that have developed in the body. This feature does not allow the ailment to develop again. Some of the pathogens even go unnoticed by us. When they appear, the body reacts so quickly that the infection sometimes does not have any chance of victory.
Cytokines
Considering the characteristics of adaptive immunity, it is necessary to pay attention to such a component as cytokines. They are also produced in the body along with special cells and antibodies. Cytokines act as signaling molecules. They have an important role to play at all stages of the immune response. There are several different types of these molecules.
Some cytokines are responsible for the reaction of innate, while others acquired immunity. This category includes many different factors. One of the most important is the transfer factor. It plays an important role in the formation of immunity.
Immune diseases
Adaptive immunity sometimes fails. This happens due to the negative impact of a number of factors. As a result, immune and autoimmune diseases may appear. In the first case, one or more components are absent or insufficiently produced in the protective system.
The immune response in this case is markedly reduced. As a result, the body's defense becomes inadequate. Immunodeficiency can be congenital or secondary. The first category of disorders includes hereditary defects of the immune system. With secondary immunodeficiencies, a lifestyle review is required. The factors that provoke violations (poor nutrition, stress, poor lifestyle, bad habits, etc.) need to be addressed. At the same time, immunostimulants are also prescribed.
Autoimmune pathologies are characterized by the destructive effects of immunity antibodies, which are aimed at your own body. As a result, inflammatory processes occur, caused by the malfunction of their own immunity. Cells lose their ability to identify correctly foreign pathogens. In the process of treatment, immunosuppressants are used.
Having considered the features of adaptive immunity, you can understand its mechanisms, functions, as well as characteristic features. This is one of the most important components of protecting the body.