- Immunity - types and characteristics in children in adults
- Types and Features
What is immunity
Immunity - a body immunity to various infectious agents and their toxins (poisons), as well as to various other alien organic substances.
Any alien organic substances, whether a microorganism, animal tissue or other rights, etc. antigen is called in response to the entering of which occurs in the body's immune reaction: produced antibodies capable of neutralizing it. The immune system is well remembers his own antigenic composition of the man and not normally produces antibodies to these antigens. But in some cases this occurs, a condition called autoimmune reaction.
The human immune system
The human immune system includes the thymus, bone marrow, embryonic (in utero), liver, lymphoid formation of the intestine and the appendix (appendicitis), the lymph nodes, spleen, and also found in the blood and tissue cells of bone marrow origin - lymphocytes, monocytes, and et al. Most of the cells of the immune system are constantly moving through the blood and lymph vessels in a section of the immune system and vice versa.
All immune cells interact with each other and isolated environment diverse molecules that exert regulatory action against the body's own cells and the vast - for alien. Such molecules are called cytokines.
The immune protection of the body from the "enemy" is carried out as the cells of the immune system (cellular immunity) and their metabolic products (humoral immunity).
A key role in the cellular and humoral immune mechanisms play lymphocytes white blood cells. They are divided into thymus-dependent (T-cells, they develop in the thymus) and thimic-independent (B lymphocytes that develop, bypassing the thymus in fetal liver).
Cellular immunity is carried out by blood cells capable of phagocytosis (absorption and digestion of 'outsiders'), and to the release of cytokines. All phagocytes are divided into macrophages (granular white blood cells) and macrophages (monocytes). The first place to the appearance of "outsiders" rush macrophages, for them - macrophages. Attract them to the "scene of the battle" T-lymphocytes, which are allocated to this particular matter.
Humoral immunity is carried out by B-lymphocytes that trigger the production of antibodies
Antibodies - "soldiers' immunity
. The interaction of antibody with antigen, they stick together, which contributes complement (complex system of serum proteins). Subsequently Complement destroys bacteria and viruses, and decomposition products excreted
The nature and strength of the immune response depends on the properties of the antigen (e.g., the ability of the bacteria or virus to cause disease), the amount, place of contact with the body, and so on.
Types of immunity
There is a specific immunity, which is inherited. For example, a person can not become infected with a particular infection of animals (swine fever), and animals - from human (chickenpox).
Immunity can be acquired. Natural immunity produced by a person during prolonged contact with infectious agents (if the disease is not happening). So there is, for example, individual immunity to certain infections in contact with patients. During epidemics of plague
Plague - whether justified reputation of the "black death"?
smallpox and many doctors are not sick because of the formation of such immunity
Immunity is developed and the introduction of vaccines that contain components of bacteria or viruses. There are active and passive immunity. Active immunity is developed after suffering an infectious disease or the vaccine, which contains weakened or killed pathogens (antigens). Passive immunity - this is the administration of a ready-made antibodies contained in sera. Active immunity is not formed at once (during the week), lasts a long time, passive develop immediately, but did not last long. Accordingly active immunity (vaccines) is used for the prevention and passive (serum antibodies) - for the treatment of infectious diseases.
Features of immunity in children
Immunity in children has its own characteristics. In infants and children up to a year of great importance passive immunity in which antibodies to infectious agents transmitted from the mother to the baby through the placenta. The contents of these antibodies is reduced to 6-9 months of life.
Operation own immune system
The immune system - how it works?
baby begins only after antigenic stimulation, i.e. exposure of microbes on the newborn. Of particular importance are the microorganisms that populate the gastrointestinal tract. Typically, in the first months of life the child settle in the intestine is not the most useful bacteria for digestion, so there is the charge for a long time is immunoglobulin A, which is an antibody capable of dealing with the "enemy" in place of its occurrence. Only after dysbacteriosis
Dysbacteriosis - what brings self
tested, the number of IgA decreases.
Further development of immunity in children is under the influence of an illness and vaccination.
Immunity - a basic protection of our body and if it is broken, the body becomes open to any outside influences.
Galina Romanenko