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 a pathological process, and a low concentration indicates a weak immunity.
What are antibodies? general information
Antibodies are protein compounds of 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. Antibodies produced from B-lymphocytes, plasma cells are produced, and for each antigen they are different. These protein compounds, when bound to a specific fragment of an antigen, recognize it.
Antigens and Antibodies
Foreign bodies that provoke the production of antibodies are called antigens. The body begins the synthesis of immunoglobulins on 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 activate the immune response. An antibody, entering into a chemical reaction with an antigen, promotes the release of substances whose main function is to protect the body.
A blood test for antibodies with high accuracy reveals many pathologies. What are antibodies? For the individual’s body, this is a kind of protection, and for laboratory research, these are markers of diseases. The very first antibodies begin to be synthesized in the womb. After birth, their development continues, and this process lasts throughout life. To produce certain antibodies, the 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, antibodies are produced, 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 - these antibodies are formed with liver damage or the occurrence of respiratory infections. 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 - they are not currently used for diagnostic purposes, since this is a poorly studied class of antibodies.
- E - produced with parasitic lesions and allergic reactions: edema, skin rashes, itching, rhinitis of an allergic nature.
- M - with 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 the tissue, and live only five days, then decay. Their production is carried out by mature B-cells, called plasma. The synthesis of immunoglobulin begins with the introduction of foreign substances into the body of an individual, i.e. this class is the first to respond to an irritant. The large size does not allow them to penetrate the baby through the placenta, that is, it can only be found 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. The establishment of an appropriate antigen or the presence of antibodies to infectious pathogens in the individual’s blood helps to find the cause of the disease. Definition of titles is shown in the following cases:
- identification of microbes that have been isolated;
- diagnosis of infectious pathologies;
- in order to exclude the risks of a conflicting pregnancy: blood transfusion, cesarean section, placental abruption, miscarriage.
What situations need analysis?
Immunoglobulin M in medical practice is used as a marker of immune cells and is used to:
- control of autoimmune processes, infectious pathologies;
- assessment of the functioning of the immune system;
- monitoring the effectiveness of treatment.
The doctor prescribes an IgM antibody test in the following cases:
- if a 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;
- with suspected autoimmune disease.
In order to find out what process is taking 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
Using serological analysis, the interaction of antigens with antibodies in blood serum is studied. As a result of this diagnosis, specific antibodies formed during the immune response are determined. Serological reactions are widely used to determine microbial antigens. For example, an agglutination reaction is sensitive to detect IgM antibodies and less sensitive to detect 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 to them are determined.
High credits
Reference indicators in children depend on age, and in adults - by sex. Pathology is any deviation in one direction or another from the permissible values. The reason for the increased concentration in children is associated with acute infectious diseases or inflammatory processes: diphtheria, flu, rubella, measles. A high concentration of IgM in the blood taken from the umbilical cord of the baby indicates infection with its toxoplasmosis, rubella or syphilis. In adult individuals, high antibody titers indicate pathologies such as:
- cirrhosis of the liver;
- neoplasms;
- hepatitis;
- parasitic diseases;
- rheumatoid arthritis;
- fungal infections;
- 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 lower the titer, but to eliminate the causes that provoked this condition. IgM antibodies can be higher than the permissible values when taking certain medications:
- Phenytoin;
- "Carbamazepine";
- "Methylprednisolone";
- "Estrogen";
- "Khlopromazin";
- and others.
Constant stresses, great physical exertion, exercise also provoke high titers.
Low titers
A low concentration of IgM antibodies, and, accordingly, and weak immunity lies in the following conditions:
- burns;
- lymphoma
- pathological production of antibodies with a modified chemical structure;
- radiation treatment;
- selective immunoglobulin M deficiency;
- lack of a spleen;
- uncontrolled intake of drugs;
- congenital immunoglobulin deficiency;
- the use of gold-based medicines for the treatment of autoimmune diseases of a rheumatic nature.
Chlamydia antibodies in a blood test
Chlamydia is a rather dangerous parasite that affects many organs of the individual. Therefore, early diagnosis is very important. Their penetration into the body most often occurs in an intimate relationship 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 to 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 of immunoglobulin M is noted, and after three months they are not detected, that is, they disappear.
Elevated titers, when the concentration is 1: 1000, this means that an acute stage of inflammation is going on in the body of the individual. Unlike IgM, IgG has been present in the blood for many years, and it can be detected three weeks after infection. Therefore, in patients diagnosed with chlamydia, even after a successful cure, IgG antibodies will be in the blood. If a pregnant woman has them, then she passes them through the placenta to the baby 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 titer reduction does not occur after five months of therapy, it means that the individual does not have immunity to fight, and the disease has acquired a chronic form.
Syphilis Diagnosis
Antibodies to pale treponema - what is it? This is a method for diagnosing syphilis, which, unlike others, is especially informative and reduces the false-positive or false-negative result to almost zero. The detection of total antibodies to treponema means the detection of immunoglobulins of classes such as M and G. If the individual has recently become infected or the acute phase of the disease is observed, then only antibodies M. are produced. In the chronic stage, antibodies G. Based on the results of the study, their ratio is evaluated and conclusion. Antibodies to pale treponema - what is it? This is a serological test of blood serum, based on the immunological reaction of an antigen-antibody.
Specific treponemal test
This test is used to detect 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 period, they are present in a small percentage of patients. Thus, the definition of class M immunoglobulins is used to distinguish between a long-standing or fresh infection. It is considered appropriate to analyze for antibodies M in order to diagnose congenital syphilis, since the risk of transmission of infection during delivery and during gestation is higher with fresh infection in the mother. Unlike IgG, maternal M antibodies do not cross the placenta, therefore, their detection in the blood of the baby confirms congenital syphilis. In addition, the absence of antibodies M in a baby who was born from an infected mother does not preclude congenital pathology, since they may not form at the time of the analysis.
Epstein-Barr virus
The causative agent, affecting B-lymphocytes, becomes the cause of the development of the following pathologies:
- infectious mononucleosis;
- hairy leukoplakia;
- nasopharyngeal carcinoma;
- Hodgkin's disease;
- and etc.
In general, the infection is asymptomatic. Four types of antigens are characteristic of the Epstein-Barr virus. IgM antibodies, as well as IgG, are synthesized on each of them. Initially, they are produced to the capsid antigen of the virus, and then to others. Antibodies to Epstein-Barr virus are determined by analysis of blood serum. All herpes viruses have similar symptoms, therefore, to diagnose a specific, differential diagnosis is carried out. A high level of these components is detected during the first days or six weeks after the appearance of the virus in the blood. IgM antibodies are diagnosed before the clinical presentation. Fourteen days after infection, their concentration gradually decreases. They completely disappear approximately six months after the disappearance of the symptoms of the disease.
Antibodies are in every organism, according to their class and quantity they diagnose a particular disease. In addition, he is responsible for human immunity. Analysis of biomaterial for the detection of antibody titer is an informative and very accurate way of laboratory research.