Normal immune response

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Under the electronic microscope, you can see the surface of B-cells covered with deep folds and numerous CVS (the surface of T cells smooth). On the membrane B-cell receptors are present immunoglobulin nature, their relationship with the antigen induces the cell to divide. From each parent cell is formed clone child lymphocytes producing antibodies same specificity. When these antibodies into the blood, they mark there molecules antigen for destruction by other components of the immune system, in particular complement. The complement system consists of more than 10 proteins, which in turn are activated on the cell surface, bearing complex antigen to antibody. These complexes attract macrophages that their phagocytic.
In the role of receptor B-cells immunoglobulins Ig are present in the organism in small quantities, but after stimulation of B-cell antigen and IL-2 in the lymph and blood, you receive a huge number of Ig.
Producers antibodies are plasma cells that are descendants of B-cells, stimulated by antigen and T-helper. The core of plasma cells are shifted to one side, and all the cytoplasm filled with tiny containers with ready-made antibodies. Antibody synthesis occurs continuously in a plate complex of Golgi apparatus in average for 20 minutes For the system of internal channels antibodies appear on the surface of B-cells, where they fall into the blood. Each plasma cell produces one kind of antibody and lives only a few days.
The antibody molecule consists of four amino acid chains, two of them (on 330-440 amino acids) are called heavy, and two others (220) - light. These circuits are connected together so that they form the structure of the crater, like the letter U. Each hand this letter is involved in the formation of the variable segment that recognize the antigen, according to its structure. Recognition of antigen is determined by the amino acid sequence of this variable segment.
"Leg" letters (unlike the variable zone) is a constant. It is built differently, and therefore there are five classes of immunoglobulins: M, G (there are four isotype - G1, G2, G3 and G4), A, E, and D. This classification is based on different physical-chemical and biological properties of antibodies and not on their specificity.
Listing the main participants of the immune response, will describe the progress on the example of acute viral disease, virus-Infected cells produce interferon, which boosts the first line of defense - EC-cells. Their activity reaches its peak in 1-2 days after infection. At the same time in the fight take the macrophages, They absorb the virus, the grain proteins and provide the complex class II antigens of T-helper cells and b-cells.
The complex alien molecules and antigen 1A interact only those T - and B-cells, which have to this set of specific receptor. So is the selection of cells for further reproduction and education clone. B-cell can interact with a free antigen, i.e. independently to recognize it, but T-helper takes the imprint only progressirovanii, split antigen and familiar to him antigen compatibility II class. Linking with T-cell stimulates macrophages to the production of IL-1, which, in turn, makes T-helpers active in sharing. Simultaneously with the appearance of interferon, and then the IL-1 the person has a fever, malaise, reflecting the mobilization of protective forces of the body to fight infection.
Reproduction of T cells continues as long as there stimulation by antigen-presenting macrophages. Then Mature T-helpers begin to produce IL-2. The biological effect of this second growth factor is that it promotes the maturation of T-killers. After hours b they acquire receptors to IL-2 and can kill virus-infected cells, compatible with the class I antigens. The cytotoxic effect of T-killers implemented within minutes, these cells operate faster, than the EC.