Antibodies or immunoglobulins protect an individual from viruses and pathogens. Analyzing their level in the bloodstream, assess the state of immunity and the effectiveness of pharmacotherapy. A high concentration indicates the presence of a pathological process, and a low one indicates a weak immune system.
What are antibodies? General information
Antibodies are protein compounds in blood plasma. They are formed as a response of the body to the penetration of pathogens, toxins, viruses and other antigens into it. Due to the fact that they have the ability to connect with the active sites of various bacteria and viruses, the latter lose their ability to reproduce. In addition, immunoglobulins neutralize harmful substances secreted by viruses and bacteria. Produce antibodies formed from B-lymphocytes, plasma cells, and for each antigen is different. These protein compounds, binding to a specific fragment of the antigen, recognize it.
Antigens and antibodies
Alien to the bodybodies that provoke the production of antibodies are called antigens. The body begins the synthesis of immunoglobulins for the antigen that it considers foreign. However, not all antibodies can attack the antigen, some of them are designed only to recognize foreign and hostile cells, as well as to activate the immune response. The antibody, entering into a chemical reaction with the antigen, contributes to the release of substances whose main function is to protect the body.
A blood test for antibodies with high accuracy allows you to identify many pathologies. What are antibodies? For the body of an individual, this is a kind of protection, and for a laboratory study, these are disease markers. The very first antibodies begin to be synthesized in the womb. After birth, their production continues, and this process continues throughout life. To produce certain antibodies, an individual is vaccinated. The purpose of which is to develop the necessary amount for the formation of immunity.
Classes
Depending on the disease and its stage, the production of antibodies is carried out, i.e. some are synthesized after the end of the incubation period, and others - immediately after the penetration of foreign substances. There are five classes of immunoglobulins, each of which has its own letter designation:
- G - may be present in the body of an individual throughout life. Its synthesis begins 14–21 days after the onset of the disease. This class is characterized by the development of persistent immunity to the pathogen.
- A - theseantibodies are formed when liver damage or respiratory infections occur. They appear in the blood seven to fourteen days after infection, and disappear after two or three months. If their level does not change, then this indicates the chronic nature of the disease.
- D - currently not used for diagnostic purposes, as this is a little studied class of antibodies.
- E - produced for parasitic lesions and allergic reactions: swelling, skin rashes, itching, allergic rhinitis.
- M - during infection, they are synthesized first and their level decreases within a month.
Characterization of immunoglobulin M
IgM antibodies are a special gamma-globulin fraction of proteins responsible for protective functions in the body. Due to their high molecular weight (about 900 kDa), they are also called macroglobulins. Of the total number of antibodies, they occupy only 5-10 percent. They penetrate poorly into tissues, and live only five days, then disintegrate. Their production is carried out by mature B-cells, called plasma cells. The synthesis of immunoglobulin begins when foreign substances are introduced into the body of an individual, i.e. this class reacts first to the stimulus. Their large size prevents them from getting to the baby through the placenta, i.e., it can only be detected in the blood of a pregnant woman.
Antibody titer
This term refers to the dilution of biological fluid or blood serum, as a result of which antibodies are detected. Establishment of the corresponding antigen or presence in the bloodindividual antibodies to infectious pathogens, helps to find the cause of the disease. Title detection is shown in the following cases:
- identifying microbes that have been isolated;
- diagnostics of infectious pathologies;
- in order to eliminate the risks of conflict pregnancy: blood transfusion, caesarean section, placental abruption, spontaneous abortion.
When is analysis needed?
Immunoglobulin M in medical practice is used as a marker of immunity cells and is used for the following purposes:
- control of autoimmune processes, infectious pathologies;
- evaluation of the functioning of the immune system;
- monitoring the effectiveness of treatment.
The doctor prescribes an IgM antibody test in the following cases:
- if the baby is suspected of having an infection;
- chronic diarrhea;
- with oncopathology;
- sepsis;
- chronic viral and antibacterial infections;
- cirrhosis of the liver;
- analysis of the state of the immune system;
- if an autoimmune disease is suspected.
In order to find out what process takes place in the body (acute or chronic), two classes of IgM and IgG are examined. To diagnose intrauterine infection, the test is done only for immunoglobulin M.
Serological and immunological studies
With the help of serological analysis, the interaction of antigens with antibodies in blood serum is studied. As a result of such a diagnosis, the resultingimmune response process specific antibodies. Serological tests are widely used to determine microbial antigens. For example, the agglutination test is sensitive for detecting IgM antibodies and less sensitive for detecting IgG.
The basis of immunological analysis is the specific reaction of antibodies and antigens. With their help, pathologies of bacterial, viral and parasitic etiology are identified, as well as titers for them are determined.
High Titles
Reference values in children vary by age and in adults by gender. Pathology is any deviation in one direction or another from the permissible values. The reason for the overestimated concentration in children is associated with acute infectious diseases or inflammatory processes: diphtheria, influenza, rubella, measles. A high concentration of IgM in the blood taken from the umbilical cord of the baby signals infection with toxoplasmosis, rubella or syphilis. In adult individuals, high antibody titers indicate pathologies such as:
- cirrhosis of the liver;
- new growths;
- hepatitis;
- parasitic diseases;
- rheumatoid arthritis;
- infections caused by fungi;
- diseases of the gastrointestinal tract and respiratory tract, acute and chronic.
If other classes of antibodies are below normal, and immunoglobulin M is higher, then this phenomenon indicates the development of hypermacroglobulin syndrome. The essence of therapy is not to reduce the titer, but to eliminate the causes,causing such a state of affairs. IgM antibodies may be higher than the permissible values and when taking certain medications:
- "Phenytoin";
- Carbamazepine;
- "Methylprednisolone";
- "Estrogen";
- Chlopromazine;
- and others.
Constant stress, heavy physical activity, playing sports also provoke high titers.
Low credits
Low concentration of IgM antibodies, and, accordingly, weak immunity lies in the following conditions:
- burns;
- lymphoma;
- abnormal production of antibodies with altered chemical structure;
- radiotherapy;
- selective immunoglobulin M deficiency;
- lack of spleen;
- uncontrolled drug use;
- congenital immunoglobulin deficiency;
- use of gold-based medicines for the treatment of autoimmune diseases of a rheumatic nature.
Chlamydia antibodies in blood tests
Chlamydia are quite dangerous parasites that affect many organs of the individual. Therefore, early diagnosis is very important. Their penetration into the body most often occurs during intimate relationships with the infected. To identify them, it is necessary to conduct a study to determine antibodies to chlamydia. IgM appear at the beginning of the development of the disease and indicate an acute course of the pathology or its exacerbation. On the fourth or fifth day after infection, these antibodies can be detected in the blood. On the seventh-eighth day of the development of the infectious process, the highest concentration is notedimmunoglobulin M, and after three months they are not detected, i.e. they disappear.
Increased titers, when the concentration is 1:1000 - this means that an acute stage of inflammation is going on in the body of an individual. Unlike IgM, IgG has been present in the blood for many years and can be detected three weeks after infection. Therefore, in patients diagnosed with chlamydia, even after successful treatment, IgG antibodies will be in the blood. If a pregnant woman has them, then she passes them on to the baby through the placenta and he develops immunity to chlamydia. The next type of immunoglobulin that is detected is IgA. Their presence signals the spread of infection throughout the body. If the reduction in titers does not occur after five months of therapy, it means that the individual does not have immunity to fight, and the disease has become chronic.
Diagnosis of syphilis
Antibodies to pale treponema - what is it? This is a method for diagnosing syphilis, which, unlike others, is especially informative and reduces a false positive or false negative result to almost zero. The detection of total antibodies to treponema means the detection of immunoglobulins of such classes as M and G. If the infection has occurred recently in an individual or the acute phase of the disease is observed, then only M antibodies are produced. conclusion. Antibodies to pale treponema - what is it? This is a serological study of blood serum based on immunologicalantigen-antibody reactions.
Treponemal specific test
This test is used to detect a fresh syphilis infection. Specific antibodies M to treponema are present in most patients with primary and secondary syphilis. In percentage terms, these are 88 and 76, respectively.
In the early latent (latent) period, they are present in a small percentage of patients. Thus, the determination of class M immunoglobulins is used to distinguish between old or recent infection. It is considered appropriate to test for M antibodies to diagnose congenital syphilis, since the risk of infection transmission during delivery and during the period of gestation is higher with a fresh infection in the mother. Unlike IgG, maternal M antibodies do not cross the placenta, so their detection in the blood of an infant confirms congenital syphilis. In addition, the absence of M antibodies in a baby who was born from an infected mother does not at all exclude congenital pathology, since they may not form at the time of the analysis.
Epstein-Barr virus
The pathogen, affecting B-lymphocytes, causes the development of the following pathologies:
- infectious mononucleosis;
- hairy leukoplakia;
- nasopharyngeal carcinoma;
- Hodgkin's disease;
- etc.
Most of the infection is asymptomatic. Four types of antigens are characteristic of the Epstein-Barr virus. Antibodies IgM, as well as IgG are synthesized for each of them. Initially theyare produced to the capsid antigen of the virus, and then to others. Antibodies to the Epstein-Barr virus are determined by analyzing blood serum. All herpes viruses have similar symptoms, therefore, differential diagnosis is carried out to identify a specific one. A high level of these components is detected during the first days or six weeks after the appearance of the virus in the blood. Antibodies of the IgM class are diagnosed before the appearance of a clinical picture. Fourteen days after infection, their concentration gradually decreases. They disappear completely about six months after the disappearance of the symptoms of the disease.
Antibodies are in every organism, according to their class and quantity, one or another disease is diagnosed. In addition, it is responsible for human immunity. Analysis of biomaterial for the detection of antibody titer is an informative and very accurate method of laboratory research.
