A antibody is a protein what reacts against an antigen in an animal-like organism . The antibodies, which can be found in the blood or in other body fluids, they are used by the immune system to recognize and block virus , bacteria , parasites or mushrooms .
It is important to note that each type of antibody defends the body from a specific class of antigen. When the antibody confuses healthy tissue with a harmful substance there is talk of a autoimmune disorder .
The most frequent antibody is formed by structural basic units that have four chains: two light and two heavy. He B lymphocyte He is responsible for synthesizing the antibodies, which can be divided into five classes (isotypes ) different in the case of mammals.
Although the general structure of the antibodies is similar, a certain region of the protein is very variable, resulting in the existence of millions of antibodies. This part of the protein is referred to as hypervariable region .
The wide variety of antibodies is produced by combinations of a set of genetic segments, responsible for encoding various antigen binding sites. He then experiences random mutations in this region of the gen of the antibody, increasing diversity even more.
Among the many types of antibodies, mention may be made of the anti-histological antibodies (which react against tissue antigens), the anti-nuclear antibodies (attack the antigens found on the surface of cell nuclei) and bivalent antibodies (able to fix a couple of antigen molecules that correspond on its surface), among others.
Immune system diseases
There is a set of diseases that are due to disorders in the immune or immune system and whose consequences are suffering from frequent infections. In some cases they are not very serious but the recurrence of them could mean a delicate complication for the patient.
Some of the causes of these diseases may lie in the existence of certain unusual infectious cancers, viruses, fungi or some type of bacteria that directly affects the immunity of the organism.
These disorders may be due to a decrease in the number of white blood cells, improper functioning (despite being the amount that the body needs) or other failures of the immune system.
It is worth mentioning that immunodeficiency can occur from the moment of birth, in cases where it is genetically inherited, or develop over the years due to certain external factors.
Acquired immunodeficiency, which manifests itself at an advanced age, is usually caused by a certain disease. In some cases, a minor deterioration in the defense system is generated, but in others, the most severe, the body's ability to cope with the infection can be destroyed.
One of the best known infections is caused by HIV (human immunodeficiency virus ) that is caused by the disease or acquired immunodeficiency syndrome, known under the acronym AIDS. This virus undoes white blood cells, which makes it impossible for them to respond to the threat of any external infection, making any simple disease a serious problem for that organism.
During childhood one of the main causes of conditions in the immune system is the malnutrition. If a child has malnutrition that is less than 80 percent of their appropriate weight at a body weight, it is known that the immune system will be affected and if it is 70, the condition will be serious. This happens because the deficiency of nutrients caused by this poor diet prevents the body from creating antibodies, weakening more and more and becoming vulnerable to any threat from outside.