What is cytokin?
cytokines are a group of proteins involved in congenital and adaptive immune systems. Many types of cells in the body - not only the cells of the immune system - can produce cytokines and production is generally stimulated by the presence of antigen. Cytokines carry signals from one cell to another, changing cell behavior in different ways and regulating the body's immune response to a potential threat - which could be a pathogen such as virus, bacteria or parasite or toxin. In some cases, there is inappropriate production of cytokines in response to something harmless, resulting in an allergic reaction. Cytokine proteins are usually not stored, but are synthesized if necessary.
The role of these proteins in the immune response is complex. One cytokine can affect several different cell types and can perform more than one function, while several different cytokines can perform the same function. Different cell types can react differently the same cytokine and cytokines can interact with different ways- for example, one can prevent the effects of another; Two together could cause a synergic effect; And one cytokine can stimulate the production of others. Cytokines may affect the cell that produced them - they are known as autocrine - or can affect near cells - these are known as paracrine. Less commonly could affect cells at a certain distance through blood circulation - they are known as endocrine.
Several different cytokines are connected to the congenital immune system. Chemokins affect the movement of immune cells of chemotaxic and can attract these cells to places of damage or infection. Alfa (TNF-A), interleukin 1 (IL-1) and interleukin 6 (IL-6), known jointly as endogenic pyrogens, cause fever and inflammatory infection to influence temperature control in hypothalamus and support of fat and protein to produce heat; They also stimulate chemokin production. InterferonsThey have a number of functions, including the prevention of viral replication and activation of macrophages and NK cells. In contrast, interleukin 10 (IL-10) has essentially an inhibitory effect on the immune response.
other types of cytokines play a role in the adaptive immune system. Interleukins 2, 4 and 5 (IL-2, IL-4 and IL-5) stimulate the growth and development of various immune cells. The transformation growth factor of beta (TGF-P) is mainly inhibitory, which affects the multiplication of various immune cells and also reduces the fever by blocking the effects of endogenic pyrogens. Interferon Gama (IFN-Y) is active both in both innate and adaptive immune responses.
In the bone marrow, another group of cytokines plays an important role. This group stimulates hematopoesis and mpomlčka; Growing and ripening of bone marrow leukocytes to different types. Examples are interleukins 3 and 7 (Il-3 and Il-7) and factors stimulating colonies (CSF).
Although these proteins play a crucial role in coordinating the immune response to the elimination of threats, they may sometimes worsen the conditions caused by PAtogens or yourself cause a disease. Excessive cytokine production, perhaps in response to a new and unknown pathogen, can lead to what is called a storm of cytokines that can cause serious and life -threatening tissue inflammation. It was proposed that the high rate of mortality during the 1918 influenza pandemic was caused by this effect rather than the direct effects of the virus itself. Other related problems include toxic shock, allergy and autoimmune diseases. Some cancer cells produce cytokines that help to stimulate their growth.