Homeostasis - is the body's ability to resist change and to keep moving (within certain limits - limit of normal) constancy of the composition and properties of the organism. In normal homeostasis Homeostasis: physiological mechanisms   the body is healthy, when violations occur disease.

What are antigens and their types

Antigens (AG) - is foreign substances with defined structure characterized by the origin and structure of the basic substance of the body and cause an immune response. Antigens may be ingested outside - exogenous AG, e.g., food, microbial, household. But a large portion of AG formed in the organism as mutating transformed cells, such as tumor cells - this endogenous antigen.

Antigenic substances depends on the ability of cells and in body fluids are substances recognize antigen. Antigenic molecules can be enhanced or weakened in the case of connecting them with others. Antigenic fetal cells relative to the mother, the sperm cells relative to the vagina, the blood of a person with respect to the other. The antigenicity acquired both in utero and after birth.

Immune response to antigens

In the AG's immune system gives your immune response. The immune system is a system to protect the body against antigens, its main task - to distinguish "us" from "them" and destroy the latter. For this there are two types of immunity - cellular and humoral. Cellular immunity is nonspecific, that is, certain immune cells (phagocytes) kill "outsiders", regardless of their structure and origin. Phagocytes - the vanguard of immunity, they are the first to meet AG and destroy them.

If cellular immunity could not cope with the AG, in response to the introduction of its body produces specific proteins - immunoglobulins, called antibodies (AT). This is humoral immunity. AT are strictly specific for hypertension, that is, to a certain AH produced specific antibodies.

Immune response prevents hypertension outside and their formation in the body, thus maintaining, dynamic equilibrium between hypertension and equivalent immune response.

What is the antigenic homeostasis

A child born with a sterile, but it gradually organism colonized a plurality of microorganisms which are foreign to the human organism.

Homeostasis involves the immune system, whose mission to destroy any antigen and prevent it from penetrating into the body. However, the human body needs beneficial bacterial microflora which on the one hand helps to resist pathogenic microflora and other stimulates immunity, because, in response to its introduction into the body are also formed antibodies.

Newborn children are part of the antibody to various infections from the mother, and in the first 3 - 6 months of life, these antibodies provide immunity to infections child. Children who are breastfed Breastfeeding: notes Also produced antibodies from the mother to her milk.

But gradually the antibodies derived from the mother and the baby come to an end is left alone with the infection. Especially young children are susceptible to viruses, they are infected with acute respiratory viral infections several times a year. This happens as long as the formation of antibodies to the most common viruses. And only to younger school age the number of antibodies in the body of the child becomes sufficient to protect it from constant infections. By secondary school age, the number of antibodies in children compared to their number of adults, that is formed antigenic homeostasis.

An important part of the antigenic homeostasis is to fight constantly mutating cells of the body, which becomes the more, the older body. In old age, the immune system is weakened, which is the main cause of malignant tumors, that is a violation of the antigenic homeostasis.

Violations antigenic immunity

It provides antigenic homeostasis of the immune system. Abnormalities in the immune system lead to incorrect responses to hypertension. Such reactions can be divided into three major groups:

• lack of immune response to the AG - the immune system is weakened and unable to cope with the task of protecting the body against infection or tumor development; such immunity disorders are manifested by frequent colds, the formation of chronic infectious and inflammatory diseases and the development of tumors;
• too strong (allergic) reaction - develop upon repeated administration of any antigen (ie after sensitization); during the initial introduction of the antigen into the body the formation of small amounts of antibody (sensitization), and at repeated them a large amount that causes an allergic reaction;
• antibodies to their own body tissues (autoimmunity) - occurs due to a failure in the immune system; autoimmune diseases include glomerulonephritis, Graves' disease, systemic lupus erythematosus.

The antigenic homeostasis - an important part of the overall homeostasis of the body, it depends on the state of human health.

Galina Romanenko

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