The human immune system is a collectioncells, tissues and organs that are responsible for providing protection against foreign microorganisms and substances, as well as their own cells whose genetic program is disrupted (for example, tumor cells). In the event that any damage or malfunction occurs in this system, this leads to the death of the whole organism.
Components of the human immune system
Today, the human immune system is represented as a combination of the following organs, tissues and cells:
- Central lymphoid organs (lymphoid formations of the appendix, lymphoid formations of the colon, fetal liver, bone marrow and thymus gland).
- Peripheral lymphoid organs (spleen and lymph nodes).
- Immunocompetent cells (monocytes, lymphocytes, polynuclear leukocytes, Langerhans cells and others).
At the same time for the normal functioning of the immune system are important all these cells, tissues and organs. Organ systems (digestive, urinary and others) are quite dependentfrom the level of immunity. In the event that it decreases, then the risk of developing one or other infectious diseases, as well as the appearance of both benign and malignant tumors, increases by an order of magnitude. Consequently, the body's immune system plays a huge role for its normal functioning.
How does a person's immune system work?
The immune response to the introduction of the microorganismperformed at the expense of cells such as leukocytes. They come in several varieties: neutrophils (stab, segmented, basophils and eosinophils), monocytes and lymphocytes (B-lymphocytes, T-lymphocytes and NK-lymphocytes). It is the neutrophils that first reach the site of infection and begin to destroy foreign microorganisms. In doing so, they cope better with bacteria. If viruses enter the body, then lymphocytes are much more effective against them.
Besides the fact that the human immune systemable to suppress the majority of known microorganisms, it can still “remember” many of them and in case of re-infection with them cope with the trouble much faster (and with less losses for the organism itself).
It is worth noting that the immune system, beingvery useful, can have negative effects on human activity. This is most pronounced after organ transplantation. The fact is that due to the fact that the immunity perceives the tissues of the donor organ as foreign, often a rejection reaction occurs. As a result, people have to conduct complex research and wait for a suitable donor for years. In addition, sometimes the immune system of a woman suppresses the sperm of a man that has fallen into it, since, again, it begins to consider them alien and dangerous to the body. As a result, there is the so-called immunological incompatibility of partners. In order for such a couple to have their own children, a woman has to take immunosuppressive drugs. In the case that the mother’s Rh factor is negative and the fetus is positive, then it can be immunized during the first pregnancy. As a result, the next child, if he also turns out to be a carrier of a positive Rh factor, may be subjected to a real attack from the immune system of his mother, which leads to the development of quite severe conditions that threaten both the fetus and the woman herself.
