Analysis of immune status. Immune status. General information Immune status expanded what is included

1.Medical microbiology. Subject, tasks, methods, connection with other sciences. The importance of medical microbiology in the practical activities of a doctor.
3. Microorganisms and their position in the system of the living world. Nomenclature of bacteria. Principles of classification.
6. Growth and reproduction of bacteria. Reproduction phases.
7. Nutrition of bacteria. Types and mechanisms of bacterial nutrition. Autotrophs and heterotrophs. Growth factors. Prototrophs and auxotrophs.
8. Nutrient media. Artificial nutrient media: simple, complex, general purpose, elective, differential diagnostic.
9. Bacteriological method of studying microorganisms. Principles and methods for isolating pure cultures of aerobic and anaerobic bacteria. The nature of the growth of microorganisms on liquid and solid nutrient media.
13. Spirochetes, their morphology and biological properties. Species pathogenic to humans.
14. Rickettsia, their morphology and biological properties. The role of rickettsia in infectious pathology.
15. Morphology and ultrastructure of mycoplasmas. Species pathogenic to humans.
16. Chlamydia, morphology and other biological properties. Role in pathology.
17. Fungi, their morphology and biological features. Principles of taxonomy. Diseases caused by fungi in humans.
20. Interaction of virus with cell. Life cycle phases. The concept of persistence of viruses and persistent infections.
21. Principles and methods of laboratory diagnosis of viral infections. Virus cultivation methods.
24. Structure of the bacterial genome. Mobile genetic elements, their role in the evolution of bacteria. The concept of genotype and phenotype. Types of variability: phenotypic and genotypic.
25. Bacterial plasmids, their functions and properties. Use of plasmids in genetic engineering.
26. Genetic recombinations: transformation, transduction, conjugation.
27. Genetic engineering. Use of genetic engineering methods to obtain diagnostic, preventive and therapeutic drugs.
28.Distribution of microbes in nature. Microflora of soil, water, air, methods of studying it. Characteristics of sanitary indicator microorganisms.
29. Normal microflora of the human body, its role in physiological processes and pathology. The concept of dysbacteriosis. Preparations for restoring normal microflora: eubiotics (probiotics).
31. Forms of manifestation of infection. Persistence of bacteria and viruses. The concept of relapse, reinfection, superinfection.
32. Dynamics of development of the infectious process, its periods.
33. The role of microorganisms in the infectious process. Pathogenicity and virulence. Units of measurement of virulence. The concept of pathogenicity factors.
34. Classification of pathogenicity factors according to o.V. Bukharin. Characteristics of pathogenicity factors.
35. The concept of immunity. Types of immunity.
36. Nonspecific protective factors of the body against infection. Role of I.I. Mechnikov in the formation of the cellular theory of immunity.
37. Antigens: definition, basic properties. Antigens of bacterial cells. Practical use of bacterial antigens.
38. Structure and functions of the immune system. Cooperation of immunocompetent cells. Forms of immune response.
39. Immunoglobulins, their molecular structure and properties. Immunoglobulin classes. Primary and secondary immune response. :
40. Classification of hypersensitivity according to Jail and Coombs. Stages of an allergic reaction.
41. Immediate hypersensitivity. Mechanisms of occurrence, clinical significance.
42. Anaphylactic shock and serum sickness. Causes of occurrence. Mechanism. Their warning.
43. Delayed hypersensitivity. Skin allergy tests and their use in the diagnosis of certain infectious diseases.
44. Features of antiviral, antifungal, antitumor, transplantation immunity.
45. Concept of clinical immunology. Human immune status and factors influencing it. Assessment of immune status: main indicators and methods for their determination.
46. Primary and secondary immunodeficiencies.
47. Interaction of antigen with antibody in vitro. Theory of network structures.
48. Agglutination reaction. Components, mechanism, installation methods. Application.
49. Coombs reaction. Mechanism. Components. Application.
50. Passive hemagglutination reaction. Mechanism. Components. Application.
51. Hemagglutination inhibition reaction. Mechanism. Components. Application.
53. Complement fixation reaction. Mechanism. Components. Application.
54. The reaction of neutralizing a toxin with an antitoxin, neutralizing viruses in cell culture and in the body of laboratory animals. Mechanism. Components. Staging methods. Application.
55. Immunofluorescence reaction. Mechanism. Components. Application.
56. Enzyme immunoassay. Immunoblotting. Mechanisms. Components. Application.
57. Vaccines. Definition. Modern classification of vaccines. Requirements for vaccine products.
59. Vaccine prevention. Vaccines made from killed bacteria and viruses. Cooking principles. Examples of killed vaccines. Associated vaccines. Advantages and disadvantages of killed vaccines.
60. Molecular vaccines: toxoids. Receipt. Use of toxoids for the prevention of infectious diseases. Examples of vaccines.
61. Genetically engineered vaccines. Receipt. Application. Advantages and disadvantages.
62. Vaccine therapy. The concept of therapeutic vaccines. Receipt. Application. Mechanism of action.
63. Diagnostic antigenic preparations: diagnosticums, allergens, toxins. Receipt. Application.
64. Serums. Definition. Modern classification of serums. Requirements for whey preparations.
65. Antibody preparations are serums used for the treatment and prevention of infectious diseases. Methods of obtaining. Complications during use and their prevention.
66. Antibody preparations are sera used to diagnose infectious diseases. Methods of obtaining. Application.
67. Concept of immunomodulators. Operating principle. Application.
68. Interferons. Nature, methods of production. Application. No. 99 Interferons. Nature, methods of production. Application.
69. Chemotherapy drugs. The concept of the chemotherapeutic index. The main groups of chemotherapeutic drugs, the mechanism of their antibacterial action.
71. Drug resistance of microorganisms and the mechanism of its occurrence. The concept of hospital strains of microorganisms. Ways to overcome drug resistance.
72. Methods for microbiological diagnosis of infectious diseases.
73. Causative agents of typhoid fever and paratyphoid fever. Taxonomy. Characteristic. Microbiological diagnostics. Specific prevention and treatment.
74. Pathogens of escherichiosis. Taxonomy. Characteristic. The role of Escherichia coli in normal and pathological conditions. Microbiological diagnosis of escherichiosis.
75. Pathogens of shigellosis. Taxonomy. Characteristic. Microbiological diagnostics. Specific prevention and treatment.
76. Salmonella pathogens. Taxonomy. Characteristics. Microbiological diagnosis of salmonellosis. Treatment.
77. Pathogens of cholera. Taxonomy. Characteristic. Microbiological diagnostics. Specific prevention and treatment.
78. Staphylococci. Taxonomy. Characteristic. Microbiological diagnosis of diseases caused by staphylococci. Specific prevention and treatment.
79. Streptococci. Taxonomy. Characteristic. Microbiological diagnosis of streptococcal infections. Treatment.
80. Meningococci. Taxonomy. Characteristic. Microbiological diagnosis of streptococcal infections. Treatment.
81. Gonococci. Taxonomy. Characteristic. Microbiological diagnosis of gonorrhea. Treatment.
82. Causative agent of tularemia. Taxonomy. Characteristics. Microbiological diagnostics. Specific prevention and treatment.
83. The causative agent of anthrax. Taxonomy and characteristics. Microbiological diagnostics. Specific prevention and treatment.
84. Causative agent of brucellosis. Taxonomy and characteristics. Microbiological diagnostics. Specific prevention and treatment.
85. Causative agent of plague. Taxonomy and characteristics. Microbiological diagnostics. Specific prevention and treatment.
86. Pathogens of anaerobic gas infection. Taxonomy and characteristics. Microbiological diagnostics. Specific prevention and treatment.
87. Causative agents of botulism. Taxonomy and characteristics Microbiological diagnostics. Specific prevention and treatment.
88. The causative agent of tetanus. Taxonomy and characteristics. Microbiological diagnosis and treatment.
89. Non-spore-forming anaerobes. Taxonomy. Characteristics. Microbiological diagnosis and treatment.
90. The causative agent of diphtheria. Taxonomy and characteristics. Conditionally pathogenic corynebacteria. Microbiological diagnostics. Detection of anoxic immunity. Specific prevention and treatment.
91. Pathogens of whooping cough and parawhooping cough. Taxonomy and characteristics. Microbiological diagnostics. Specific prevention and treatment.
92. Pathogens of tuberculosis. Taxonomy and characteristics. Conditionally pathogenic mycobacteria. Microbiological diagnosis of tuberculosis.
93. Actinomycetes. Taxonomy. Characteristic. Microbiological diagnostics. Treatment.
95. The causative agent of chlamydia. Taxonomy. Characteristics. Microbiological diagnostics. Treatment.
96. Causative agent of syphilis. Taxonomy. Characteristic. Microbiological diagnostics. Treatment.
97. Causative agent of leptospirosis. Taxonomy. Characteristics. Microbiological diagnostics. Specific prevention. Treatment.
98. Causative agent of borreliosis. Taxonomy. Characteristics. Microbiological diagnostics.
99. Clinical microbiology, its tasks. Vbi, features of the cause of occurrence. The role of conditionally pathogenic microorganisms in the occurrence of nosocomial infections.
100. Classification of mushrooms. Characteristic. Role in pathology. Laboratory diagnostics. Treatment.
101. Classification of mycoses. Superficial and deep mycoses. Yeast-like fungi of the genus Candida. Role in human pathology.
102. The causative agent of influenza. Taxonomy. Characteristic. Laboratory diagnostics. Specific prevention and treatment.
103. The causative agent of polio. Taxonomy and characteristics. Laboratory diagnostics. Specific prevention.
104. Pathogens of hepatitis a and e. Taxonomy. Characteristics. Laboratory diagnostics. Specific prevention.
105. Causative agent of tick-borne encephalitis. Taxonomy. Characteristics. Laboratory diagnostics. Specific prevention.
106. Rabies agent. Taxonomy. Characteristics. Laboratory diagnostics. Specific prevention.
107. The causative agent of rubella. Taxonomy. Characteristic. Laboratory diagnostics. Specific prevention.
108. Measles virus. Taxonomy. Characteristic. Laboratory diagnostics. Specific prevention.
109. Causative agent of mumps. Taxonomy. Characteristic. Laboratory diagnostics. Specific prevention.
V.Clinic
I. Epidemiology
110. Herpes infection: taxonomy, characteristics of pathogens. Laboratory diagnostics. Specific prevention and treatment.
111. The causative agent of smallpox. Taxonomy. Characteristics. Laboratory diagnostics. Specific prevention of smallpox at the present stage
Assessment of immune status carried out in the clinic for organ and tissue transplantation, autoimmune diseases, allergies, to identify immunological deficiency in various infectious and somatic diseases, to monitor the effectiveness of treatment of diseases associated with disorders of the immune system. Depending on the capabilities of the laboratory, assessment of immune status is most often based on determining a set of the following indicators:
1) general clinical examination;
2) the state of natural resistance factors;
3) humoral immunity;
4) cellular immunity;
5) additional tests.
During a general clinical examination take into account the patient’s complaints, anamnesis, clinical symptoms, results of a general blood test (including the absolute number of lymphocytes), data from a biochemical study.
Humoral immunity determined by the level of immunoglobulins of classes G, M, A, D, E in the blood serum, the amount of specific antibodies, immunoglobulin catabolism, immediate hypersensitivity, the indicator of B-lymphocytes in the peripheral blood, blast transformation of B-lymphocytes under the influence of B-cell mitogens and other tests .
State of cellular immunity assessed by the number of T-lymphocytes, as well as subpopulations of T-lymphocytes in the peripheral blood, blast transformation of T-lymphocytes under the influence of T-cell mitogens, determination of thymic hormones, the level of secreted cytokines, as well as skin tests with allergens, contact sensitization with dinitrochlorobenzene. To perform skin allergy tests, antigens to which there should normally be sensitization are used, for example, the Mantoux test with tuberculin. The body's ability to induce a primary immune response can be provided by contact sensitization with dinitrochlorobenzene.
Asadditional tests To assess the immune status, you can use tests such as determination of bactericidal™ in blood serum, titration of C3 and C4 components of complement, determination of C-reactive protein in blood serum, determination of rheumatoid factors and other autoantibodies.
Thus, the assessment of the immune status is carried out on the basis of a large number of laboratory tests that allow assessing the state of both the humoral and cellular components of the immune system, and factors of nonspecific resistance. All tests are divided into two groups: 1st and 2nd level tests. Level 1 tests can be performed in any primary care clinical immunology laboratory and are used for the initial identification of individuals with obvious immunopathology. For more accurate diagnosis, level 2 tests are used.
Concept of clinical immunology. Human immune status and factors influencing it .
Clinical immunology is a clinical and laboratory discipline that studies the diagnosis and treatment of patients with various diseases and pathological conditions based on immunological mechanisms, as well as conditions in the treatment and prevention of which immunotherapy drugs play a leading role.
Immune status- this is the structural and functional state of the individual’s immune system, determined by a set of clinical and laboratory immunological indicators.
Thus, immune status characterizes the anatomical and functional state of the immune system, i.e. its ability to mount an immune response to a specific antigen at a given time.
For immune status the following factors influence:
Climatic-geographical; social; environmental (physical, chemical and biological); “medical” (the effect of drugs, surgical interventions, stress, etc.).
Among the climatic and geographical factors The immune status is influenced by temperature, humidity, solar radiation, day length, etc. For example, the phagocytic reaction and allergic skin tests are less pronounced in residents of northern regions than in southerners. The Epstein-Barr virus causes an infectious disease in people of the white race - mononucleosis, in people of the Negroid race - oncopathology (Burkitt's lymphoma), and in people of the yellow race - a completely different oncopathology (nasopharyngeal carcinoma), and only in men. Africans are less susceptible to diphtheria than Europeans.
To social factors that influence the immune status include nutrition, living conditions, occupational hazards, etc. A balanced and rational diet is important, since food supplies the body with substances necessary for the synthesis of immunoglobulins, for the construction of immunocompetent cells and their functioning . It is especially important that essential amino acids and vitamins, especially A and C, are present in the diet.
Living conditions have a significant impact on the immune status of the body. Living in poor housing conditions leads to a decrease in general physiological reactivity, respectively immunoreactivity, which is often accompanied by an increase in the level of infectious morbidity.
Occupational hazards have a great influence on the immune status, since a person spends a significant part of his life at work. Industrial factors that can have an adverse effect on the body and reduce immunoreactivity include ionizing radiation, chemicals, microbes and their metabolic products, temperature, noise, vibration, etc. Radiation sources are now very widespread in various industries industry (energy, mining, chemical, aerospace, etc.).
Salts of heavy metals, aromatic, alkylating compounds and other chemicals, including detergents, disinfectants, pesticides, and pesticides, which are widely used in practice, have an adverse effect on the immune status. Workers in chemical, petrochemical, metallurgical industries, etc. are exposed to such occupational hazards.
Microbes and their metabolic products (most often proteins and their complexes) have an adverse effect on the immune status of the body among workers in biotechnological industries associated with the production of antibiotics, vaccines, enzymes, hormones, feed protein, etc.
Factors such as low or high temperature, noise, vibration, and insufficient lighting can reduce immunoreactivity by having an indirect effect on the immune system through the nervous and endocrine systems, which are in close relationship with the immune system.
Environmental factors have a global effect on human immune status, first of all, environmental pollution with radioactive substances (spent fuel from nuclear reactors, leakage of radionuclides from reactors during accidents), widespread use of pesticides in agriculture, emissions from chemical enterprises and vehicles, biotechnological industries.
Various diagnostic and therapeutic medical procedures influence the immune status, drug therapy, stress. Unreasonable and frequent use of radiography and radioisotope scanning can affect the immune system. Immunoreactivity changes after trauma and surgery. Many medications, including antibiotics, can have immunosuppressive side effects, especially with long-term use. Stress leads to disruptions in the functioning of the T-immune system, acting primarily through the central nervous system.

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Immune status- These are indicators of the functioning of the immune system. It includes the study of quantitative indicators of the components of the immune system and determination of their functional activity.

Indications for prescribing an immunological status study There may be any suspicion of inadequate functioning of the immune system: severe infectious diseases, the presence of chronic or often recurrent infectious diseases, the presence of foci of chronic inflammation, connective tissue diseases, autoimmune processes, etc. Among the disorders of the immune system, the following should be highlighted first:

Insufficiency of the immune system or immunodeficiency is a reduced activity of the immune system, developing as a result of a reduced number of components of the immune system or their insufficient functional activity.
Hyperreactivity of the immune system, in other words, excessive activity, which can lead to a severe course of the disease that caused it.
Autoimmune reactions (the immune system attacks its own tissues).

Assessing the immune status allows you to clarify the diagnosis of the disease, as well as determine treatment tactics if abnormalities in the functioning of the immune system are detected (immunotropic drugs can be prescribed or replacement therapy can be carried out by administering immune sera, immunoglobulins, leukocyte mass, interferon preparations).

Based on the results of this analysis, one can judge whether the human body is able to protect itself from bacteria and viruses that constantly attack it, whether it has enough cells and molecules designed to maintain the constancy of the internal environment, and also what the ratio of such cells and molecules is.

The immunogram takes into account the number of cells (leukocytes, macrophages or phagocytes), their percentage and functional activity, as well as the “substances” that these cells produce - immunoglobulins (Ig) of classes A, M, G, E, components of the complement system. To find out all this, a number of blood cells are examined - leukocytes: granulocytes, monocytes, but primarily lymphocytes. Another important indicator is the amount of immunoglobulins that protect the body from microbes. Along with this, the presence and activity of interferons is determined (these are molecules that protect us from germs, viruses and tumor growth). The ability of blood cells to respond to incoming microorganisms is also tested.

Immunoglobulin testing provides information about the state of the humoral immune system. This is used in the diagnosis of primary and secondary immunodeficiencies, autoimmune, infectious, hematological and other diseases. Changes in immunological parameters can be a manifestation of the body’s normal reaction to the influence of physiological or pathological factors (with different patterns of changes at different stages of the disease), reflect excessive activation, depletion of the immune system, or characterize a congenital or acquired defect of individual parts of the immune system.

There are four types of immunoglobulins:

IgM- this type of antibody appears first upon contact with an antigen (microbe). An increase in their titer, or content in the blood, indicates an acute inflammatory process.

IgG- antibodies of this class appear some time after contact with the antigen. They participate in the fight against microbes: they bind to antigens on the surface of the bacterial cell; then other plasma proteins (the so-called complement) join them, as a result of which the bacterial cell is lysed (its membrane ruptures). In addition, IgG is involved in some allergic reactions.

IgA prevent the penetration of microorganisms through mucous membranes.

IgE- antibodies of this class interact with receptors located on mast cells (connective tissue cells that secrete physiologically active substances: heparin, histamine, serotonin, etc. they are involved in the processes of inflammation, blood clotting, etc.) and basophils. As a result, histamine and other allergy mediators are released. An allergic reaction itself develops.

One of the most important indicators of immune status is complement components C3, C4. Complement is a set of immune proteins contained in fresh blood serum. They participate in the bactericidal action of blood.

C3- a central component of the complement system, a protein of the acute phase of inflammation. This is an essential part of the defense system against infections. It is formed in the liver, macrophages, fibroblasts, lymphoid tissue and skin. Therefore, disruption of their normal state significantly affects this component.

C4- a glycoprotein synthesized in the lungs and bone tissue. C4 supports phagocytosis, increases the permeability of the vascular wall, and is involved in the neutralization of viruses. This test is usually prescribed for suspected autoimmune disorders, repeated bacterial infections; during dynamic observation of patients with systemic autoimmune diseases; in the diagnosis of systemic lupus erythematosus, rheumatoid vasculitis and other diseases.

Another indicator of immune status is cryoglobulin, an abnormal protein that can be present in the blood in a number of diseases. At low temperatures, cryoglobulins become insoluble, leading to blockage of small blood vessels located in the fingers and toes in cold weather, causing the characteristic rash. The presence of cryoglobulins (cryoglobulinemia) can be a symptom of various diseases, including macroglobulinemia, systemic lupus erythematosus, as well as a number of infectious diseases.

Circulating immune complexes (CIC)

CECs are circulating immune complexes, the level of which increases during acute infections and autoimmune diseases.

Immune status is the structural and functional state of an individual’s immune system, determined by a set of clinical and laboratory immunological parameters.

Thus, immune status (syn. immune profile, immunoreactivity) characterizes the anatomical and functional state of the immune system, i.e., its ability to mount an immune response to a specific antigen at a given time.

The presence of an immune system in a person automatically implies his ability to mount an immune response, but the strength and form of the immune response to the same antigen can vary widely among different people. The entry of an antigen into the body in one person causes predominantly antibody formation, in another - the development of hypersensitivity, in a third - mainly the formation of immunological tolerance, etc. The immune response to the same antigen in different individuals can vary not only in form, but and by strength, i.e. by degree of expression, for example, by the level of antibodies, resistance to infection, etc.

Not only do individual individuals differ in immunoreactivity, but within the same person immunoreactivity can fluctuate at different periods of his life. Thus, the immune status of an adult and a child, especially a newborn or the first year of life, when the immune system is still functionally immature, differs significantly. In children, it is easier to induce immunological tolerance; they have lower titers of serum antibodies during immunization. The immune status of a young and an elderly person is also different. This is partly due to the condition of the thymus, which is considered the “biological clock” of the immune system. Age-related involution of the thymus leads to a slow decline in T-cell reactions with aging, a decrease in the ability to recognize “self” and “foreign”, therefore, in old age, in particular, the frequency of malignant neoplasms is higher. With air

The frequency of detection of autoantibodies is also increasing, and therefore aging is sometimes considered as a chronically ongoing autoaggression.

Immune status is subject not only to age, but also to daily fluctuations depending on biorhythm. These fluctuations are due to changes in hormonal levels and other reasons. Thus, when assessing immune status, significant individual variability in immunological parameters, even in normal conditions, should be taken into account.

The immune system is phylogenetically one of the young (along with the nervous and endocrine) and very labile to various external influences. Almost any, even the most insignificant, external impact on the human body leads to a change in the state of its immune system. The following factors influence the immune status:

Climatic-geographical;

Social;

Environmental (physical, chemical and biological);

“medical” (the effect of drugs, surgical interventions, stress, etc.).

Among climatic and geographical factors, the immune status is influenced by temperature, humidity, solar radiation, day length, etc. For example, the phagocytic reaction and allergic skin tests are less pronounced in residents of northern regions than in southerners. The Epstein-Barr virus causes an infectious disease in people of the white race - mononucleosis, in people of the Negroid race - oncopathology (Burkitt's lymphoma), and in people of the yellow race - a completely different oncopathology (nasopharyngeal carcinoma), and only in men. Africans are less susceptible to diphtheria than Europeans.

Social factors that influence immune status include nutrition, living conditions, occupational hazards, etc. A balanced and rational diet is important, since food supplies the body with substances necessary for the synthesis

immunoglobulins, for the construction of immunocompetent cells and their functioning. It is especially important that the diet contains essential amino acids and vitamins, especially A and C.

Living conditions have a significant impact on the immune status of the body. Living in poor housing conditions leads to a decrease in general physiological reactivity, respectively immunoreactivity, which is often accompanied by an increase in the level of infectious morbidity.

Occupational hazards have a great influence on the immune status, since a person spends a significant part of his life at work. Industrial factors that can have an adverse effect on the body and reduce immunoreactivity include ionizing radiation, chemicals, microbes and their metabolic products, temperature, noise, vibration, etc. Radiation sources are now very widespread in various industries industry (energy, mining, chemical, aerospace, etc.).

Salts of heavy metals, aromatic, alkylating compounds and other chemicals, including detergents, disinfectants, pesticides, and pesticides, which are widely used in practice, have an adverse effect on the immune status. Workers in chemical, petrochemical, metallurgical industries, etc. are exposed to such occupational hazards.

Microbes and their metabolic products (most often proteins and their complexes) have an adverse effect on the immune status of the body among workers in biotechnological industries associated with the production of antibiotics, vaccines, enzymes, hormones, feed protein, etc.

Factors such as low or high temperature, noise, vibration, and insufficient lighting can reduce immunoreactivity by having an indirect effect on the immune system through the nervous and endocrine systems, which are in close relationship with the immune system.

Environmental factors have a global effect on human immune status, primarily environmental pollution with radioactive substances (spent fuel from nuclear reactors, leakage of radionuclides from reactors during accidents), the widespread use of pesticides in agriculture, emissions from chemical enterprises and vehicles, and biotechnological industries.

The immune status is influenced by various diagnostic and therapeutic medical procedures, drug therapy, and stress. Unreasonable and frequent use of radiography and radioisotope scanning can affect the immune system. Immunoreactivity changes after trauma and surgery. Many medications, including antibiotics, can have immunosuppressive side effects, especially with long-term use. Stress leads to disruptions in the functioning of the T-immune system, acting primarily through the central nervous system.

Despite the variability of immunological parameters in normal conditions, immune status can be determined by performing a set of laboratory tests, including assessment of the state of nonspecific resistance factors, humoral (B-system) and cellular (T-system) immunity.

Assessment of immune status is carried out in the clinic during organ and tissue transplantation, autoimmune diseases, allergies, to identify immunological deficiency in various infectious and somatic diseases, to monitor the effectiveness of treatment of diseases associated with disorders of the immune system. Depending on the capabilities of the laboratory, assessment of immune status is most often based on determining a set of the following indicators:

1) general clinical examination;

2) the state of natural resistance factors;

3) humoral immunity;

4) cellular immunity;

5) additional tests.

During a general clinical examination take into account the patient’s complaints, anamnesis, clinical

clinical symptoms, results of a general blood test (including the absolute number of lymphocytes), data from a biochemical study.

The doctor’s acquaintance with the patient begins, as a rule, with familiarization with his passport data (age) and complaints. Already at this stage, the doctor can find out about the patient’s profession and work experience (presence of occupational hazards). Of the complaints expressed, attention should be paid to recurrent opportunistic infections and allergies.

When examining a patient, pay attention to the cleanliness of the skin and mucous membranes, on which manifestations of opportunistic infections and allergies can be detected.

During palpation and percussion, attention is paid to the condition of the central (thymus) and peripheral (lymph nodes, spleen) organs of the immune system, their size, adhesion to surrounding tissues, and pain on palpation.

During percussion and auscultation, symptoms characteristic of opportunistic infections affecting internal organs are recorded.

The clinical section of the examination ends with a general blood test, which gives an idea of the state of immunocompetent cells (absolute number of lymphocytes, phagocytes).

When assessing the state of natural resistance factors determine phagocytosis, complement, interferon status, colonization resistance. The functional activity of phagocytes is determined by their mobility, adhesion, absorption, cell degranulation, intracellular killing and breakdown of captured particles, and the formation of reactive oxygen species. For this purpose, tests such as determination of the phagocytic index, NBT test (nitro blue tetrazolium), chemiluminescence, etc. are used. The state of the complement system is determined in the hemolysis reaction (the result is taken into account by 50% hemolysis). Interferon status is detected by titrating the level of interferon on a cell culture.

feron in blood serum. Colonization resistance is determined by the degree of dysbiosis of various biotopes of the body (most often the colon).

Humoral immunity determined by the level of immunoglobulins of classes G, M, A, D, E in the blood serum, the amount of specific antibodies, immunoglobulin catabolism, immediate hypersensitivity, the indicator of B-lymphocytes in the peripheral blood, blast formation of B-lymphocytes under the influence of B-cell mitogens and other tests .

To determine the concentration of immunoglobulins of different classes in blood serum, radial immunodiffusion according to Mancini is usually used. The titer of specific antibodies (blood group isohemagglutinins, antibodies formed after vaccination, natural antibodies) in serum is determined in various immunological reactions (agglutination, RPGA, ELISA and other tests). To determine the catabolism of immunoglobulins, radioisotope labels are used. The number of B-lymphocytes in the peripheral blood is determined by determining specific receptors on cells using monoclonal antibodies (cluster analysis) or in the rosette formation reaction (EAC-ROK erythrocytes, in the presence of antibodies and complement, form rosettes with B-lymphocytes). The functional state of B-lymphocytes is determined in the blast transformation reaction by stimulating cells with mitogens, such as tuberculin, laconas, etc. Under optimal conditions for culturing B-lymphocytes with mitogens, the rate of transformation into blasts can reach 80%. Blasts are counted under a microscope, using special histochemical staining methods, or using a radioactive label - based on the inclusion of tritium-labeled thymidine in the DNA of the cell.

State of cellular immunity assessed by the number of T-lymphocytes, as well as subpopulations of T-lymphocytes in the peripheral blood, blast transformation of T-lymphocytes under the influence of T-cell mitogens, determination of thymic hormones, the level of secreted cytokines, as well as skin tests with allergens, contact sensitization with dinitrochlorobenzene. To perform skin allergy tests, antigens to which there should normally be sensitization are used, for example, the Mantoux test with tuberculin. The ability of the organiza-

Contact sensitization with dinitrochlorobenzene can reduce the induction of a primary immune response.

To determine the number of T-lymphocytes in peripheral blood, the E-ROK rosette reaction is used, since sheep erythrocytes form spontaneous rosettes with T-lymphocytes, and to determine the number of subpopulations of T-lymphocytes, the EA-ROK rosette reaction is used. Rosette formation reactions are used due to the fact that on the T-helper membrane there is a receptor for the Fc fragment of immunoglobulin M, and on the T-suppressor membrane there is a receptor for the Fc fragment of immunoglobulin G, therefore T-helpers form rosettes with erythrocytes associated with anti-erythrocyte antibodies of the IgM class, and suppressors form rosettes with erythrocytes associated with anti-erythrocyte antibodies of the IgG class. However, rosette reactions for the differentiation of T lymphocytes have given way to a more accurate and modern method for determining populations and subpopulations of T lymphocytes - cluster analysis based on the use of monoclonal antibodies to lymphocyte receptors. After determining the number of T-lymphocyte subpopulations, the ratio of helpers and suppressors, i.e. T4/T8 lymphocytes, is calculated, which is normally approximately 2.

Blast transformation of T-lymphocytes, i.e., their functional activity, is determined by stimulation with T-cell mitogens, such as con-canavalin A or phytohemagglutinin. Under the influence of mitogens, mature lymphocytes are transformed into lymphoblasts, which can be counted under a microscope or detected by radioactive labeling.

To assess the state of thymic function, determination of the levels of al1-thymosin and thymulin, which reflect the function of epithelial cells of the thymic stroma, is most often used.

To determine the level of secreted immunocytokines (interleukins, myelopeptides, etc.), enzyme-linked immunosorbent methods are used, based on the use of monoclonal antibodies to two different cytokine epitopes. For this purpose, the reaction of inhibition of leukocyte migration can also be used.

As additional tests To assess the immune status, you can use tests such as determining the bactericidal capacity of blood serum, titrating C3 and C4 components of complement, determining the content of C-reactive protein in blood serum, determining rheumatoid factors and other autoantibodies.

Table 12.1. Tests to assess immune status

Level 1 tests	Level 2 tests
1. Determination of the number and morphology of T- and B-lymphocytes in peripheral blood (abs. and %)	1. Histochemical analysis of lymphoid organs
2. Cluster analysis or EAC rosette formation	2. Analysis of surface markers of mononuclear cells using monoclonal antibodies
3. Determination of serum immunoglobulins of classes M. (J, A, D, E	3. Blast formation of B and T lymphocytes
4. Determination of phagocytic activity of leukocytes	4. Determination of cytotoxicity
5. Skin allergic gestations	5. Determination of the activity of enzymes associated with immune deficiency
6. X-ray and fluoroscopy of lymphoid organs, as well as other internal organs (primarily the lungs), depending on clinical indications	6. Determination of synthesis and secretion of cytokines
7. Determination of thymus hormones
8. Analysis of respiratory burst of phagocytes
9. Determination of complement components
10. Analysis of mixed cell cultures

Thus, the assessment of the immune status is carried out on the basis of a large number of laboratory tests, which allow assessing the state of both the humoral and cellular components of the immune system, and factors of nonspecific resistance. It is obvious that some of the tests used are complex to perform, require expensive immunochemical reagents, modern laboratory equipment, as well as highly qualified personnel, and therefore they are feasible in a limited number of laboratories. Therefore, on the recommendation of R.V. Petrov, all tests are divided into two groups: tests of the 1st and 2nd levels. Level 1 tests can be performed in any primary care clinical immunology laboratory and are used for the initial identification of individuals with obvious immunopathology. For more accurate diagnosis, level 2 tests are used. The list of tests of the 1st and 2nd levels is presented in table. 12.1.

Pathology of the immune system

There are two types of immune system disorders: a) immune deficiency or immunodeficiencies, when there is a defect, i.e.

deviation in one or more immune response mechanisms; b) excessive activation of immune mechanisms leading to the development allergic or autoimmune diseases. Immunoproliferative diseases stand somewhat apart.

12.4.1. Immunodeficiencies

Immunodeficiencies are disorders of the normal immune status caused by a defect in one or more immune response mechanisms.

There are primary, or congenital (genetic), and secondary, or acquired, immunodeficiencies.

The clinical picture of various immunodeficiencies is similar. Immunodeficiency states themselves do not have characteristic clinical symptoms, but are usually accompanied by the following manifestations: infectious complications; hematological disorders; gastrointestinal disorders; autoimmune processes; tumors; allergic reactions; congenital malformations.

Based on the above, diagnosis of immunodeficiency is carried out according to anamnesis (frequent infectious diseases, tumors, autoimmune processes, allergies, etc.), according to clinical symptoms (opportunistic infection, allergies, tumors, condition of lymph nodes, malformations, etc.), as well as according to tests in vitro And in vivo, morphological studies (histological studies of central and peripheral organs of the immune system), which are mentioned above.

12.4.1.1. Primary, or congenital, immunodeficiency

As primary immunodeficiencies, conditions are distinguished in which a violation of the immune humoral and cellular mechanisms is associated with a genetic block, that is, genetically determined by the inability of the body to implement one or another link of immunological reactivity. Immune system disorders can affect both the main specific links in the functioning of the immune system and the factors that determine nonspecific resistance. Combined and selective variants of immune disorders are possible. Depending on the level and nature of the disorders, humoral, cellular and combined immunodeficiencies are distinguished.

Congenital immunodeficiency syndromes and diseases are quite rare. The causes of congenital immunodeficiencies can be chromosome duplication, point mutations, defects in nucleic acid metabolism enzymes, genetically determined membrane disorders, genome damage in the embryonic period, etc. As a rule, primary immunodeficiencies appear in the early stages of the postnatal period and are inherited in an autosomal recessive manner. Primary immunodeficiencies can manifest themselves in the form of insufficiency of phagocytosis, complement system, humoral immunity (B-system), cellular immunity (T-system) or in the form of combined immunological deficiency.

Insufficiency of phagocytosis caused either by a decrease in the number of phagocytes, or

their functional inferiority. Periodic neutropenia underlies cyclic disorders of hematopoiesis in general. First of all, this process manifests itself in a decrease in the number of granulocytes, as well as in a change in the number of monocytes. Despite the fact that neutropenia is not accompanied by a deficiency of humoral or cellular immunity, it does cause an increased risk of infectious diseases, especially those caused by highly virulent bacteria. Functional defects in phagocytosis can be caused by disturbances at any stage of the phagocytosis process (chemotaxis, endocytosis, intracellular digestion, etc.).

Complement deficiency is rare. The most common defect in the synthesis of complement components is caused by hereditary deficiency of the C1 esterase inhibitor, which is clinically manifested by angioedema. A low concentration of C1 esterase inhibitor allows for continuous partial activation of C1 followed by consumption of C4 and C2. In a number of diseases, especially those that occur with the formation of immune complexes, activation of complement leads to its excessive consumption. In this case, the number of C1, C4, C2 and S3 decreases most significantly.

Insufficiency of humoral immunity expressed as dysgammaglobulinemia And agammaglobulinemia. Agammaglobulinemia is caused by a violation of the synthesis of immunoglobulins or their accelerated decay with unchanged synthesis. With agammaglobulinemia, there are no immunoglobulins in the blood of patients and in such individuals, first of all, antitoxic and antibacterial immunity is impaired, i.e. those types of immunity in which antibodies play a leading role. Dysgammaglobulinemia is caused by a selective deficiency of one of the classes of immunoglobulins or their combined deficiency, while the total level of serum immunoglobulins may remain within normal limits or even increase due to a compensatory increase in the synthesis of immunoglobulins of other classes. Most

Often there is a selective deficiency of IgG with a simultaneously high level of IgM, a deficiency of IgG and IgA with a high level of IgM, and a selective deficiency of IgA. There is a deficiency of certain subclasses of immunoglobulins and a defect in the light chains of immunoglobulins.

Insufficiency of cellular immunity is caused by a violation of the functional activity of T cells. Since T-lymphocytes are involved in the manifestation of the functional activity of B-cells, combined immunodeficiency (damage to the T- and B-cell units) is more common than selective T-cell immunodeficiency. However, isolated T-cell immunodeficiencies have been described, such as alymphacytosis (Nozelof syndrome), DiGeorge syndrome(congenital aplasia of the thymus and parathyroid glands), immunodeficiency in Down syndrome, immunodeficiency in dwarfism. Persons with such T-cell immunodeficiency suffer from antiviral, antifungal, antitumor and transplantation immunity, i.e. those types of immunity in which the main role belongs to reactions from the T-cell component of the immune system. The first signs of cellular immunodeficiency are mycosis, recurrent viral infections, complications after vaccination with live vaccines (poliomyelitis, BCG, etc.). As a rule, persons with insufficient cellular immunity die in childhood, less often in adolescence, from severe recurrent opportunistic infections or malignant tumors.

Combined immunodeficiency develops with a combination of disorders of the T- and B-links of the immune system. This is the most severe form of immunodeficiency. Combined forms are more common than selective forms; as a rule, they are associated with a violation of the central organs of the immune system. Depending on the severity of the defect, the predisposition to infectious diseases is expressed to varying degrees. With significant immune disorders, frequent bacterial and viral infections and mycotic lesions are observed, which leads to death at an early age.

outcome. An immune defect at the stem cell level is caused by a number of disorders: a defect in stem cells itself, a block of T- and B-cell differentiation, primary T-cell immunodeficiency, in which a decrease in immunoregulatory function leads to the development of B-cell immunodeficiency. The defect can be caused by both endogenous and exogenous factors. Functional disorders can manifest themselves even if morphologically the cells of patients do not differ from the norm. In combined immunodeficiencies, the leading role belongs to the T-cell defect.

12.4.1.2. Secondary, or acquired, immunodeficiencies

Secondary immunodeficiencies, unlike primary ones, develop in individuals with a normally functioning immune system from birth. They are formed under the influence of the environment at the phenotypic level and are caused by dysfunction of the immune system as a result of various diseases or adverse effects on the body. With secondary immunodeficiencies, the T- and B-immune systems and nonspecific resistance factors can be affected, and their combinations are also possible. Secondary immunodeficiencies are much more common than primary ones. Secondary immunodeficiencies, as a rule, are transient and amenable to immunocorrection, i.e., restoration of normal activity of the immune system.

Secondary immunodeficiencies can occur: after previous infections (especially viral ones) and invasions (protozoal and helminth infections); for burn disease; with uremia; for tumors; with metabolic disorders and exhaustion; with dysbiosis; for severe injuries, extensive surgical operations, especially those performed under general anesthesia; under irradiation, exposure to chemicals; with aging, as well as medications associated with taking medications.

According to the time of occurrence they distinguish antenatal(for example, non-hereditary forms of DiGeorge syndrome), perinatal(eg, neonatal neutropenia

caused by maternal isosensitization to fetal neutrophil antigens) and postnatal secondary immunodeficiencies.

According to the clinical course there are compensated, subcompensated And decompensated forms of secondary immunodeficiencies. The compensated form is accompanied by increased susceptibility of the body to infectious agents that cause opportunistic infections. The subcompensated form is characterized by a tendency to chronic infectious processes. The decompensated form manifests itself in the form of generalized infections caused by opportunistic microbes (OPM) and malignant neoplasms.

There is a known division of secondary immunodeficiencies into:

Physiological:

♦ newborns,

♦ puberty,

♦ pregnancy and lactation,

♦ aging,

♦ biorhythmicity;

Environmental:

♦ seasonal,

♦ endogenous intoxications,

♦ radiation,

Pathological:

♦ post-infectious,

♦ stressful,

♦ regulatory and metabolic,

♦ medications,

♦ oncological. Immunodeficiencies, both primary and

especially secondary ones, are widespread among people. They are the cause of many diseases and pathological conditions, and therefore require prevention and treatment with the help of immunotropic drugs. Methods of immunocorrection are described in section. 12.5.

12.4.2. Autoimmune diseases

Autoimmune diseases (autoaggressive diseases) are diseases in the pathogenesis of which autosensitization plays a decisive role.

There are autoimmune reactions and autoimmune diseases, which are based on the interaction of components of the immune system with their own healthy cells and tissues. Autoimmune diseases sometimes include immune complex diseases.

Autoimmune reactions are observed normally in healthy individuals, as well as in pathology. In the first case, they occur continuously, and their action is reduced to the removal of dying, aging, diseased cells, modified by any influences. They are the initial component of the immune response to various antigens. These reactions are beneficial to the body and do not develop into disease.

Autoimmune diseases, or autoallergies, are less common. These pathological conditions are based on autoimmune reactions with barrier cross-reacting antigens, the formation of “forbidden” clones of immunocompetent cells that react with their own normal tissues, genetically programmed weakness of the immune response to a specific antigen, insufficiency of T-suppressors, blockade of lymphocyte receptors and other reasons. They can also be a consequence of taking medications.

There are autoimmune diseases organ-specific, non-organ-specific And mixed. Organ-specific diseases include diseases in which autoantibodies are specific to one or a group of structural elements of cells and tissues of one organ that have antigenic properties. Most often, these are beyond-barrier antigens, for which there is no congenital tolerance, for example, in the case of Hashimoto’s thyroiditis, primary myxedema, thyrotoxicosis, pernicious anemia, etc.). Organospecific diseases include pathological processes in which autoantibodies react, as indicated, to the structural elements of cells and tissues of a given or even another organism that has cross antigenic structures, an example of which can be antinuclear antibodies in systemic lupus erythematosus, rheumatoid

Table 12.2. Autoimmune diseases

Diseases with an established immunopathological nature	Diseases whose immunopathological nature is assumed
Hemolytic anemia due to heat autoantibodies	Primary biliary cirrhosis of the liver
Hemolytic anemia with cold hemagglutinins	Pemphigus vulgaris and pemphigoid
Immunologically caused infertility	Idiopathic Addison's disease
Hashimoto's thyroiditis	Idiopathic hypoparathyroidism
Immunothrombotic and drowning	Post-vaccination encephalitis
Cold hemoglobinuria	Periarteritis nodosa
Sympathetic ophthalmia	Dermatomyositis or polymyositis
Pernicious anemia	Scleroderma
Autoimmune bleeding disorder	Nonspecific ulcerative colitis
Chronic active hepatitis
Systemic lupus erythematosus Rheumatoid arthritis	Hyperthyroidism
Chronic glomerulonephritis

arthritis. Mixed diseases include both of the above mechanisms.

Quite often, normal autoantibodies can be found that do not cause visible symptoms of the disease. They are found in completely healthy people, for example, rheumatoid and antinuclear factors. It can be quite difficult to prove that the visible clinical picture of the disease is a consequence of an autoimmune process. The detection of antibodies to autoantigens does not yet allow us to draw a conclusion about the cause-and-effect relationship of the disease with autoimmune reactions. To confirm this, it is necessary to: identify an immune response to an autoantigen related to the disease; identify it; passively transfer the disease and provoke the disease with the corresponding antigen in an animal experiment. In table 12.2 presents the main human autoimmune diseases.

A classic example of an autoimmune disease is Hashimoto's autoimmune thyroiditis. This is an imperceptibly beginning, diffuse enlargement of the thyroid gland, which is accompanied by a decrease in its function. The disease affects women more often than men. Histologically, ob-

extensive lymphoid infiltration with small remains of glandular tissue. In almost all cases of autoimmune thyroiditis, high titers of antibodies to thyroid antigens, primarily to thyroglobulin and microsomal antigen, are detected. Antibodies are determined by RPGA or immunofluorescence reaction (RIF). Antinuclear antibodies are also often detected. The pathogenesis of Hashimoto's thyroiditis is not fully understood. Although autoantibodies to thyroid antigens are of the IgG class and can cross the placenta, children born to affected mothers do not show noticeable symptoms of the disease. With Hashimoto's thyroiditis, lymphocytes appear that are sensitized to thyroglobulin and microsomal antigen, so we can assume that the disease is based mainly on cell-mediated immune reactions.

Under certain conditions, antibodies to cell surface antigens may not destroy it, but, on the contrary, stimulate it. This is observed in thyrotoxicosis. Blood serum from patients with thyrotoxicosis can stimulate the activity of the thyroid gland. The stimulating factor has the properties of specific antibodies to the thyroid gland. It blocks the binding of thyroid-stimulating hormone to the membrane of thyroid cells, and itself acts as a thyroid-stimulating hormone.

The stimulating factor passes through the placenta, so children born to mothers with thyrotoxicosis are diagnosed with neonatal hyperthyroidism, which resolves a few weeks after birth as maternal IgG decays.

Immune reactions may play a role in cell destruction in acute and chronic hepatitis. Autoimmune reactions underlie the pathogenesis of diseases such as primary biliary cirrhosis, chronic active hepatitis and cryptogenic cirrhosis. Chronically active hepatitis is typically characterized by a combination of hypergammaglobulinemia with infiltration of liver tissue by lymphocytes and plasma cells. In a high percentage of cases, antinuclear and antimitochondrial antibodies are detected, as well as antibodies to smooth muscles and rheumatoid factor that often accompany chronic inflammatory liver diseases. Organ-specific autoantibodies are found in the blood serum of approximately 20% of patients, while specifically sensitized liver cells, detected using fluorescent antibodies, are detected in 80% of cases. Apparently, the liver functions as an immunosorbent for organ-specific autoantibodies. It is likely that immunopathology is based on sensitization of lymphocytes by liver antigens. Lymphocytes from patients with chronic active hepatitis secrete a factor that inhibits leukocyte migration in the presence of a specific liver antigen. Chronic active hepatitis is a progressive disease.

Nonspecific indicators of immune status

Immunodiagnostics – this is the use of immunological reactions and methods for the purpose of assessing immune status, laboratory diagnosis of diseases, as well as for identifying antigens.

All immunodiagnostic methods are divided into 2 groups:

General non-specific methods , characterizing the state of various parts of the immune system: lymphocytes, granulocytes, macrophages, complement. They are usually used to identify a defect in SI, i.e. for immunodeficiencies.

Specific methods , allowing the identification of antibodies, immune T-lymphocytes, antigens in the human body or pathogen antigens in the external environment. These methods are used to diagnose infections, allergies, and autoimmune diseases.

Immune status – this is the state of SI of a healthy or sick person at a certain moment of ontogenesis under specific environmental conditions.

In particular, the immune status of a child differs from that of an adult. It also changes under the influence of adverse influences.

To assess the immune status, the determination of nonspecific and specific indicators is used. Assessment of immune status is the process of obtaining a set of quantitative and functional indicators that reflect the state of the SI. It is carried out to identify the nature of immunopathology - immunodeficiency and allergic diseases.

To do this, first, a medical history is taken from the patient and a general clinical examination is performed. What is important in it is the blood formula - the number of leukocytes of different types: neutrophils, eosinophils, basophils, monocytes, lymphocytes. Leukocytosis - an increase in the total number of leukocytes (more than 9x10 9 / l) is often observed during infections; leukopenia - a decrease in their number (less than 4 x10 9 / l) - with autoallergy; eosinophilia - an increase in the number (more than 3%) of eosinophils with exogenous allergies, etc. However, these data are usually insufficient and a more detailed definition of populations, subpopulations of leukocytes and humoral immune factors is necessary.

Characteristics of T-lymphocytes

1. Determine the total number of leukocytes, blood formula and the number of lymphocytes. Normally, lymphocytes are 20-36% among other leukocytes (about 2000 cells in 1 mm 3 of blood).

2. Count percentage and number of T-lymphocytes. Normally, among blood lymphocytes there are 50-70% of them (1000-1400 cells in 1 mm 3 of blood).

A simple method for determining T cells: counting the number (percentage) of lymphocytes that form rosettes with sheep erythrocytes using CD2-AG:

an equal volume of 1% suspension of washed sheep erythrocytes is added to the leukocyte suspension and incubated at 37 0 C for 15 minutes and overnight at 4 0 C;

the sediment is resuspended, a solution of glutaraldehyde is added to a final concentration of 0.06% to fix the rosettes, and smears are immediately made;

the smears are dried, fixed with alcohol and stained according to Romanovsky-Giemsa;

count the percentage of T-lymphocytes that have bound three or more red blood cells;

Currently, the general population of T lymphocytes is detected using labeled monoclonal antibodies to CD antigens (CD2, CD3) in an immune fluorescence reaction (taking into account the results on a fluorescence microscope, on a flow cytometer) or in a reaction with particles coated with such antibodies. Normally, in a person’s blood, among all lymphocytes, 55-80% are T cells.

3. Determine the content of T-helpers and T-suppressors using monoclonal antibodies to CD4 (Tx) and CD8 (Tc) antigens.

In humans, 33-46% Tx, 17-25% Tc are normally found in the blood, the Tx/Tc ratio = 1.4-2.0 - the immunoregulatory index. In case of illness, this index changes. For example, with AIDS it decreases (0.04), because are inhibited by Tx (the receptor for the AIDS virus is the Tx CD4 antigen). For autoimmune and allergic diseases, the index is greater than 2.0.

4. To identify activated T cells, IL-2 receptors (CD25), HLA-DR antigens and CD71 (transferrin receptor) are determined.

5. Determine the level of various cytokines in the blood (usually using an enzyme immunoassay).

The functional indicators of T-lymphocytes are also studied: proliferative activity (see RBTL, RPML), cytotoxic and cytokine activity. T-lymphocyte counts decrease in T-cell immunodeficiencies.

Characteristics of B lymphocytes

1. The total number of B lymphocytes can be determined using monoclonal antibodies to antigens CD19-CD22, CD72. Antibodies to immunoglobulins, which are found on the surface of B lymphocytes, are also used. B lymphocytes make up 17-25% of all lymphocytes (600-800 cells in 1 mm 3 of blood). Sometimes B lymphocytes are identified that have receptors for mouse erythrocytes (10-15%), constituting only part of the B subpopulation.

2. Products of B-lymphocytes - immunoglobulins G, M, A classes in blood serum and various biological fluids are determined using radial immunodiffusion in agar – Mancini precipitation reactions.

To do this, pour 2% agar mixed with anti-IgG antibodies onto one glass plate (or Petri dish); on the second plate - with antibodies against IgM, on the 3rd - against IgA. After solidification, wells with a diameter of 2 mm are made in the agar. Standard serum with a known concentration of IgG, IgM, IgA is added to one row of wells on each plate. The patient's blood serum to be tested is added to other wells.

Rice. 5.1. Simple radial immunodiffusion in agar for the determination of antigens (immunoglobulins)

Immunoglobulins diffuse into the agar and a precipitation ring zone is formed at the meeting point with the antibodies that are in the agar. The diameter of this ring depends on the concentration of Ig (the more Ig, the larger the diameter). The diameter of the precipitation zone is measured for three dilutions of standard serum and a graph of the dependence of the square of the diameter of the precipitation ring (D) on the amount of Ig in the blood serum is plotted on semi-logarithmic paper (Fig. 5.1). Then the diameter of the precipitation ring of the test serum is measured, plotted on the plotted graph and the concentration of immunoglobulin is determined. To determine secretory IgA (in saliva, etc.), a similar method is used in two versions: IgA (a-chain) and its secretory component are determined using appropriate antibodies.

Standards for adults: 0.8-2 g/l IgM; 8.0-13.0 g/l IgG; 1.4-3.0 g/l IgA. In newborns, the IgG level is close to the maternal level, IgM and IgA are present in trace concentrations; by 4-6 months. the IgG level drops to 5-6 g/l and then increases. With normal development of children, the level of immunoglobulins by the age of 2 is close to their values in adults.

The level of secretory IgA in saliva is 0.03-0.4 g/l.

With immunodeficiency, the level of immunoglobulins decreases (hypogammaglobulinemia), and with stimulation of SI and inflammation, it increases (hypergammaglobulinemia).

The level of natural (against blood group antigens, animal red blood cells, etc.) and immune (to common bacterial and viral antigens, vaccines) antibodies is determined. It is reduced (or antibodies are absent) in immunodeficiencies

Characteristics of the granulocyte and monocyte system

1. Determine the number of leukocytes in the blood and the ratio of their types (neutrophils, basophils, eosinophils, monocytes).

2. Evaluate absorption and digestive activity of phagocytes: A suspension of a washed daily culture of staphylococci is added to a suspension of leukocytes or a drop of blood. Prepare 3 samples, incubate at 37 0 C, 1st sample for 45 minutes, 2nd - 60 minutes, 3rd - 90 minutes. Smears are made, dried, fixed with ethanol and stained according to Romanovsky.

The phagocytic index and phagocytic number are determined.

Phagocytic number – this is the average number of particles or microorganisms in one phagocyte (the norm for staphylococci is 6-12, candida is 2-4).

Phagocytic index– this is the number of phagocytes participating in phagocytosis, having absorbed particles (normal – 60-80%).

Evaluation of indicators at different time intervals allows us to assess the dynamics of phagocytosis. Normally, after 90 minutes, the phagocytic index should be lower than after 45 minutes and 60 minutes, due to the digestion of microbes. If digestion is disrupted, it does not change.

Digestion microbes can be assessed by plating leukocyte lysates (after incubation with microbes) on nutrient media and counting the grown colonies. The method involves the use of living microorganisms as an object of phagocytosis. After incubation with microbes (see above), phagocytes are pelleted by centrifugation, washed and lysed. Their lysates are plated on a solid nutrient medium. The digestive activity of phagocytes is assessed by the number of grown colonies.

Metabolic activity phagocytes are determined in Nitro blue tetrazolium reduction test (NST test) after painting them with a 0.25% solution of this dye. Normally, nitro blue tetrazolium stains (diffusely and in the form of blue clumps) 15-18% of neutrophils; during infections, their number increases to 40% or more.

Indicators of phagocytes decrease with corresponding immunodeficiencies, and increase with a favorable course of infection.

3. Differentiation, activation and adhesion antigens (CD14, CD11, CD18, HLA-DR, etc.) are determined on phagocytes using monoclonal antibodies.

4. Receptors for the C3 component of complement, immunoglobulins, etc. are identified.

5. Spontaneous and directed migration (chemotaxis) is assessed.

6. Determine the ability to secrete cytokines (IL-1, TNF, etc.) and their level in the blood.

Characteristics of the complement system

1. Determine the hemolytic activity of complement in the hemolysis reaction using the hemolytic system. This system consists of sheep red blood cells treated with hemolytic serum.

The determination of complement is based on the ability of its activation products to cause lysis of red blood cells coated with antibodies. The degree of hemolysis is used to judge the hemolytic activity of complement.

The hemolytic unit (CH50) is used as a unit of measurement for complement - the amount of complement that causes 50% lysis of a 3% suspension of erythrocytes sensitized by antibodies at a temperature of 37 0 C for 45 minutes. Complement titration comes down to determining the number of CH50 hemolytic units in a specific volume of serum. To do this, a standard amount of sensitized erythrocytes is added to various doses of serum. Then, using the red blood cell lysis scale with distilled water, the number of CH50 units is found.

The degree of hemolysis during complement titration can be determined by photometric methods (using a spectrophotometer, photocolorimeter, nephelometer) or visually by comparing the intensity of hemolysis in test tubes with a standard scale of lysed erythrocytes.

2. Activation products C4a, C3a, C5a, etc. are identified.

A study of the immunological status is carried out in case of any suspicion of an inadequate immune system: in the presence of chronic or frequently manifested infectious diseases, in severe infections, the presence of foci of chronic inflammation, connective tissue diseases, autoimmune processes, etc. In these cases, it is necessary to contact an immunologist. The doctor will prescribe immunity. Based on the results of the study, a prescription is compiled, which is deciphered by the attending physician.

Immune status is assessed using screening tests. The standard test includes counting the absolute number of neutrophils, leukocytes, platelets and lymphocytes, the concentration of serum immunoglobulins (IgG, IgA and IgM), and performing skin tests for delayed-type hypersensitivity. Deviations in indicators can be a normal reaction of the body to the action of pathological or physiological factors, they also reflect depletion of the immune system or excessive activation.

In a more detailed study of the immune status, the functional activity and number of humoral and cellular components of the immune system are determined.

What does immune status show?

This type of study allows you to find out information about the state of the immune system. It is used in the diagnosis of primary and secondary immunodeficiencies, lymphoproliferative, autoimmune, hematological, and infectious diseases. The study may reveal the following dysfunctions of the immune system: its insufficiency or immunodeficiency, hyperreactivity, autoimmune reactions.

Reduced activity develops as a result of a decrease in the number of components of the immune system or their insufficient activity. An overactive immune system can lead to a severe course of the disease that caused it. In autoimmune reactions, the immune system attacks its own tissues. This process is observed as a result of a breakdown in tolerance to antigens of body tissues.

Deviations from the norm in the immunogram characterize an acquired or congenital defect of individual parts of the immune system.

The immunological status allows you to clarify the diagnosis and determine the necessary treatment tactics. If abnormalities in the functioning of the immune system are detected, the patient is prescribed special medications (immunostimulants, immunosuppressors, immunomodulators). Replacement therapy can be carried out (administration of serums, leukocyte mass, immunoglobulins, interferons).