Humoral immunity and the history of its study. Pasteur did not know why vaccinations protect against infectious diseases. He thought that microbes “eat away” from the body something they needed.

6.3. IMMUNOLOGICAL STUDIES.

Main function immune system is to control the constancy of the internal environment of the body and remove pathogenic microbes or foreign molecules. The mechanisms of innate immunity play an important role in performing this function. They are also called nonspecific protection factors, because they protect the body from various exogenous and endogenous aggressions, and their protective functions lack selectivity. To the system innate immunity include phagocytic cells of blood and tissues, natural killer cells, as well as molecules produced by these cells (complement system, interleukins, interferons, etc.).

The mechanisms of a specific immune response are activated only after contact with the antigen, and protection is carried out by highly specialized cells of the immune system. Recognition and elimination of foreign agents is carried out by lymphocytes ( cellular immunity), as well as the antibodies produced and secreted by them - immunoglobulins (humoral immunity). All these components are closely interconnected; the place of their functional cooperation is the organs and tissues of the body’s immune system. In a hematology clinic, methods for studying humoral and cellular immunity, as well as the phagocyte system, are usually used.

6.3.1. Study of the humoral component of immunity.

The concentrations of immunoglobulins of classes M, G, A in blood serum, as well as secretory immunoglobulin A (SIgA) and S-components in saliva and other secretions are the most important parameters of the humoral part of the immune system. Methods for the quantitative assessment of immunoglobulins in biological media can be divided into several groups according to the principles underlying them: gel immunoprecipitation, nephelometry or turbodimetry, enzyme-linked immunosorbent assay and radioimmunoassay. They are based on comparing the concentration of immunoglobulins in the test object with a standard solution of a specified concentration.

In immunological studies, the most widely used method is radial immunodiffusion according to Mancini. It is based on the fact that when an antigen (AG) and an antibody (AT) belonging to a certain class of immunoglobulins meet in an agar gel, they interact, and the resulting precipitate precipitates in the form of visually detectable zones or stripes. The diameter of the precipitation ring is proportional to the immunoglobulin concentration. Normally, the content of immunoglobulins in blood serum is: IgG - 13.9±0.64 g/l, IgA - 2.82±0.19 g/l, IgM - 1.18±0.06 g/l.

Laser nephelometry is based on recording the light flux that is scattered by an AG-AT complex suspended in an optically transparent medium. The principle of turbodimetry is based on recording the light absorbed by the formed AG-AT complex. The great advantage of kinetic nephelometry is the speed of obtaining results (several minutes; for comparison: Mancini’s method for IgG and IgA - 24 hours, for IgM - 48 hours).

Due to its high sensitivity, enzyme-linked immunosorbent assay (ELISA) is used to determine minor immunoglobulins IgD and IgE in serum, as well as to determine all classes and subclasses of immunoglobulins in the supernatants of cultures of peripheral blood lymphocytes stimulated with B-mitogens: bacterial lipopolysaccharide (LPS), mitogen plant origin PWM, antibodies against immunoglobulin m-chains.

Immunoglobulin deficiency can be congenital or acquired. The causes of immunoglobulin deficiency may be: defects in the proliferation, differentiation and functions of B-lymphocytes, dysregulation of immunoglobulin synthesis or switching to another isotype associated with defects in T-helper cells or corresponding cytokines, general insufficiency of protein synthesis, accelerated catabolism of immunoglobulin molecules or their destruction by proteolytic enzymes .

An example of a genetic defect is Bruton's agammaglobulinemia, which occurs due to a mutation in the gene encoding a tyrosine kinase that is required for B cell differentiation. As a result, B-lymphocyte precursors are unable to differentiate into mature B-lymphocytes. Such patients lack mature B lymphocytes, plasma cells, and do not have any immunoglobulins.

Malignant transformation of B lymphocytes leads to the selective proliferation of one cell clone and to the production of antibodies of one class and one specificity. Such cases belong to monoclonal gammopathies and are manifested by variable immunodeficiencies. An example of a secondary immunodeficiency that develops as a result of malignant transformation of B-lymphocytes is multiple myeloma, in which a large number of homogeneous protein - monoclonal immunoglobulin secreted by a malignant clone of B cells. Excess light chains of immunoglobulins produced by the same cells are excreted through the kidneys and are detected in the urine in the form of Bence Jones protein.

Impaired synthesis of immunoglobulins is observed in lymphogranulomatosis, non-Hodgkin's lymphomas, and chronic lymphocytic leukemia. Treatment of oncohematological diseases with cytostatic drugs, steroids, and X-ray irradiation can cause a significant decrease in the level of immunoglobulins.

6.3.2. Study of cellular immunity.

To assess cellular immunity, a set of immunological tests is used, among which the most widespread are: 1) determination of delayed-type hypersensitivity using skin tests; 2) study of the proliferative activity of lymphocytes; 3) quantitative assessment of populations and subpopulations of lymphocytes; 4) determination of the level of secreted cytokines; 5) reaction of inhibition of leukocyte migration.

6.3.2.1. Skin tests.

Skin tests are analogous to tuberculin tests. Since these reactions are mediated by T lymphocytes, only T-dependent antigens are selected as antigens, for example, mumps virus, purified tuberculin, candida antigen, diphtheria or tetanus toxoid, trichophyton antigen, hemocyanin.

These antigens are administered intradermally, and the reaction is recorded based on the size of the inflammatory focus after 24-48 hours. The skin test is an integral reaction that evaluates several stages of the immune response (antigen recognition, chemotaxis, cytokine synthesis). The main disadvantage of this test is the difficulty in standardizing the inflammatory response.

The results of assessing cellular immunity using skin tests are fairly consistent in both men and women aged 16 to 65 years. With age, cellular immunity decreases, which is manifested by a decrease in the ability to give positive reactions. There is a correlation between skin tests and increased morbidity (infections, malignancies) or mortality in certain groups of patients. Therefore, skin tests can also be considered prognostic.

6.3.2.2. Determination of proliferative activity of lymphocytes.

Determination of the proliferative response of peripheral blood lymphocytes is the most important indicator of the functional activity of these cells. Phytohemagglutinin (PHA), concanavalin A (Con A) are used as T-cell mitogens, and Laconia mitogen (ML) for B-cells, as well as allogeneic cells. The most commonly used specific antigens are PPD, candida antigens, streptokinase-streptodornase, diphtheria and tetanus toxoids.

Some T-mitogens react with different subpopulations of T-cells: Con A predominantly activates T-suppressors, PHA - T-helpers for the synthesis of immunoglobulins. When assessing the results of a proliferative response to mitogens, it should be taken into account that these agents are polyclonal stimulators, and a positive result indicates that regulatory cells in the body exist and can respond to the appropriate stimulus.

Currently, only a radiometric method using 3 H- and 14 C-labeled thymidine is used to assess the proliferative response to T-mitogens or alloantigens. Stimulated lymphocytes are incubated with the isotope for 6-24 hours, followed by sedimentation of the cells on special filters and the blast transformation reaction is taken into account using liquid scintillation b-counters.

This reaction can be weakened by T-cell deficiencies (ataxia-telangiectasia, genetically determined thymic aplasia - DiGeorge syndrome), oncohematological diseases, especially in the terminal stage, and secondary immunodeficiencies.

6.3.2.3. Quantification of lymphocyte populations and subpopulations.

The study of T-cell subpopulations was previously carried out using the E-rosette formation reaction, based on the fact that one of the markers of T-lymphocytes is the surface glycoprotein - E-receptor (currently designated as CD2), capable of interacting with the membrane structure of sheep erythrocytes (E -rosette formation) and with the adhesion molecule LFA-3 on human erythrocytes - auto-rosette formation (auto-ROC). This marker appears on the membrane of precursor T lymphocytes in the thymus and is retained on mature T lymphocytes in the peripheral circulation. The CD2 cluster is found on the surface of natural killer (NK) cells, lymphokine-activated killer (LAK) cells, which have the morphology of large granular lymphocytes, as well as non-lymphoid cells. Thus, the E-rosette reaction is an indicator of the sum of the listed cells carrying the CD2 antigen. Therefore, it is not recommended to use E-rosette formation for T cell identification.

To assess subpopulations of T-lymphocytes, the theophylline test was also previously used, which is currently not used due to low specificity.

The development of modern technology for assessing various subpopulations of lymphocytes is associated with: 1) development and standardization of the panel monoclonal antibodies(MAT) to various cell surface differentiation antigens; 2) the emergence of a new generation of flow cytometric equipment; 3)improving computerized data processing methods.

Currently, using MAT, more than 165 surface antigens of leukocytes have been identified, their molecular weight, chemical structure, and function have been determined. Leukocyte differentiation antigens are designated "CD" (cluster of differentiation) and are numbered according to the chronology of their discovery. By identifying surface differentiation markers, it is possible to determine the population and subpopulation of cells, the stage of their differentiation and activation, functional activity and interaction with other cells.

The most significant surface markers are: for determining mature T lymphocytes - CD3, T helper/inducer cells - CD4, T cytotoxic/suppressor cells - CD8, natural killer (NK) cells - CD16, CD56 and CD57, early activation markers - CD25, CD71 , HLA-DR. Determination of surface immunoglobulins continues to be one of the main methods for identifying B lymphocytes. A reliable method for their determination is also the detection of CD19, CD20 and CD22 using MAT.

The best method for identifying surface markers is flow cytometry, the essence of which is to determine the heterogeneity of cell populations based on the expressed cell surface markers. In a hematology clinic, the main tasks of flow cytometry are: 1) immunophenotyping of leukemia and lymphomas; 2) analysis of the distribution of the cell population by cycle phases (DNA cytometry); 3) immunophenotyping of lymphocytes, assessment of intracellular production of cytokines by various cell populations; 4) analysis of the processes of activation and proliferation of cells of the immune system; 5) identification and monitoring of minimal residual disease.

Immunophenotyping of acute leukemia.

Immunophenotyping of acute leukemia using flow cytometry is carried out in two stages: first, the type of leukemia is determined (B- or T-acute lymphoblastic leukemia, acute myeloid leukemia), then subvariants of the disease (B 1 - B 5 - B-cell variants, T 1 - T 4 - variants of T-cell acute lymphoblastic leukemia, M0-M7 variants of acute myeloid leukemia) - tables 6.3.1-6.3.4.

Table 6.3.1.

Panel of markers for the first stage of immunophenotyping.

Table 6.3.2.

Immunological classification of B-lineage acute lymphoblastic leukemia.

Designations: cy - cytoplasmic expression of the antigen; s - surface expression of antigen; +/- most positive cases; + positive; - negative.

Table 6.3.3.

Immunological classification of T-linear acute lymphoblastic leukemia.

Designations: cy - cytoplasmic expression; s - superficial;

+/- - most positive cases; -/+ - most negative cases; + - positive; - negative.

Table 6.3.4.

Cytochemical, cytogenetic and immunophenotypic properties of acute myeloid leukemia

Abbreviations: Glyc.A - glycophorin; MP - myeperoxidase; SE - specific esterase; NSE is a nonspecific esterase.

Determination of the level of secreted cytokines

The main methodological approach for determining the ability of T-lymphocytes and other cells to produce cytokines is their activation by various stimulants: for example, T-cells - T-mitogens (PHA, Con A), macrophages - lipopolysaccharide of enterobacteria with identification of the corresponding cytokines in the supernatants. For these purposes, biological (use of a cell line sensitive to a given cytokine), enzyme-linked immunosorbent and radioimmune methods can be used. The most promising are enzyme immunoassay methods based on the use of monoclonal antibodies to two different cytokine epitopes.

Leukocyte migration inhibition reaction

The reaction of inhibition of leukocyte migration (RTML) is based on the ability of T-lymphocytes specific to a given antigen, when interacting with it, to synthesize a set of cytokines that activate phagocytic cells. One of the manifestations of this process is the inhibition of the migratory properties of leukocytes. This property plays an important role in protecting the body from foreign agents, as it promotes the accumulation of phagocytic cells in the inflammatory focus. Determination of migration inhibitory factor (MIF) has proven to be a valuable test for assessing the functional activity of T lymphocytes and specific sensitization. In connection with the development of the doctrine of cytokines, it became clear that they are the ones who activate and inhibit the movement of phagocytic cells, and the main factor in this activation is g-interferon. RTML can be used to assess both the intensity of chemotaxis (migration ability) of leukocytes in various diseases of the immune system, and to identify cellular immunity to various antigens and autoantigens.

Study of the function of phagocytic cells.

The process of phagocytosis consists of a number of sequential and interconnected stages. These include motility, chemotaxis, adhesion, absorption, degranulation, formation active forms oxygen and nitrogen, killing and splitting of the object of phagocytosis.

Determination of leukocyte chemotaxis is carried out by migration method in microfiltration chambers or in agarose gel under the influence of various chemotactic factors (chemoattractants), which include some N-formyl peptides of bacterial origin, complement components (C3a and C5a), leukotrienes, platelet-activating factor, IL-8, etc. .d. All these substances can accumulate in the inflammatory focus and affect the movement of phagocytes.

Study of the synthesis and expression of adhesion molecules.

Their surface receptors, called selectins and integrins, are responsible for the adhesive properties of neutrophils and monocytes. With the help of selectins, phagocytes “roll” along the surface of endothelial cells before they are firmly attached to this surface with the help of integrins.

A. Study of humoral immunity

1. Determination of the number of B-lymphocytes. The cell membrane of lymphocytes contains many glycoproteins that can be detected by flow cytometry using monoclonal antibodies. Some of these glycoproteins are specific for certain cell types, such as T-, B- and NK-lymphocytes, various subpopulations of T-lymphocytes, monocytes, and even for certain stages of their maturation and differentiation. These molecules are usually designated CD. The functions of many CDs have now been defined (see Table 18.8). When assessing the results of the study, it is necessary to take into account the age of the patient. In addition, it is necessary to constantly monitor the quality of reagents and compliance with the procedure, since even a slight violation of it distorts the results of the study. Determination of B-lymphocytes using flow cytometry is based on the detection of immunoglobulins fixed on the cell surface, CD19 and CD20 (see Table 18.8). In older children and adults, B lymphocytes make up 10-20% of all blood lymphocytes; in children younger age there are more of them.

2. Determination of antibody titer. If humoral immunity is suspected, the titer of antibodies to protein and polysaccharide antigens is assessed. They are usually determined after vaccination or infection.

A. Antibodies to protein antigens. In most cases, IgG to diphtheria and tetanus toxoids before and 2-4 weeks after DPT vaccinations or ADS. Since almost all adults are vaccinated with DTP, the level of antibodies after booster vaccination serves as an indicator of the secondary immune response. Antibodies to the PRP antigen can also be detected after administration of the Haemophilus influenzae type B vaccine. Although this antigen is a polysaccharide, it acts as a protein antigen in the conjugate vaccine. Antibodies are sometimes tested after immunization inactivated vaccine against polio and recombinant vaccine against hepatitis B. If immunodeficiency is suspected, live viral vaccines are contraindicated.

b. Antibodies to polysaccharide antigens. To assess the humoral immune response to polysaccharide antigens, pneumococcal and meningococcal vaccine, not containing protein carriers. The antibody titer is determined before and 3-4 weeks after vaccination. In some research laboratories, an unconjugate vaccine against Haemophilus influenzae type B is used for this purpose. The results are evaluated taking into account the age of the patient. Thus, in children under 2 years of age, the immune response to polysaccharide antigens is weak; in some children it remains so up to 5 years of age. In this regard, the use of polysaccharide vaccines in young children is inappropriate and even contraindicated, since it can lead to immunological tolerance and ineffectiveness of revaccination at an older age.

V. Assessment of primary and secondary humoral immune response. To determine the clearance of the antigen, the level of IgM (in the primary immune response) and IgG (in the secondary immune response), bacteriophage fihi 174 is used as a protein antigen. bacterial virus, safe for humans. To assess the primary humoral immune response, gastropod hemocyanin, recombinant hepatitis B vaccine, monomeric flagellin, and tick-borne encephalitis vaccine are also used.

d. Natural antibodies(isohemagglutinins, antibodies to streptolysin O, heterophilic antibodies, for example antibodies to sheep red blood cells) are normally present in the serum of almost all people. This is explained by the fact that the antigens against which these antibodies are directed are widespread and are contained in food products, inhaled particles, microflora respiratory tract.

3. Determination of IgG subclasses. If for recurrent bacterial respiratory tract infections general level IgG is normal or slightly reduced, or an isolated IgA deficiency is detected; determination of IgG subclasses is indicated. In this case, you can find IgG deficiency 2 (IgG 2 makes up about 20% of IgG), which can be isolated or combined with IgA or IgG 4 deficiency. It should be remembered that the functional assessment of the humoral immune response is more informative method research than quantitation IgG subclasses. Yes, when normal level IgG 2 often has a reduced level of antibodies to polysaccharide antigens of Streptococcus pneumoniae. Along with this, congenital IgG 2 deficiency is possible due to impaired synthesis heavy chains, in the absence of any clinical manifestations immunodeficiency.

4. Determination of IgA. Isolated deficiency secretory IgA with normal serum IgA levels is rare. As a rule, there is a simultaneous deficiency of secretory and serum IgA. Isolated IgA deficiency is not clinically manifested or is accompanied by mild infections upper respiratory tract. This is due to the fact that with IgA deficiency, the level of IgG in the serum and IgM in the secretions of the mucous membranes increase compensatoryly. IgA levels are measured in tears, saliva and other body fluids. There are two subclasses of IgA - IgA 1 and IgA 2. In the blood and secretions of the respiratory tract, IgA 1 predominates, in the secretions of the gastrointestinal tract - IgA 2. Normal indicators levels of IgA 1 and IgA 2.

5. Synthesis of immunoglobulins in vitro. This study assesses the production of IgM, IgG and IgA by stimulated B lymphocytes. By mixing T- and B-lymphocytes from healthy and sick people treated with different stimulants, the function of T-helper and B-lymphocytes can be assessed. In most cases, antibody deficiency is caused by impaired differentiation of B lymphocytes into plasma cells.

6. Lymph node biopsy if primary immunodeficiency is suspected, it is usually not performed. It is indicated only in cases where the diagnosis is unclear and the patient has enlarged lymph nodes, which requires the exclusion of hemoblastosis. The biopsy is usually performed 5-7 days after antigenic stimulation. The antigen is injected into an area from which lymph flows into a group of lymph nodes, one of which is subject to biopsy. With insufficiency of humoral immunity in the lymph node, the number of plasma cells is reduced, the number of primary follicles is increased, secondary follicles are absent, the thickness of the cortex is reduced, restructuring of the lymph node tissue is observed, and sometimes the number of macrophages and dendritic cells increases.

The quantitative content of immunoglobulins (IgA, IgM, IgG) is the main indicator of the humoral immune response and is necessary for assessing the functional usefulness of the immune system and diagnostics pathological disorders her work.

Determination of the level of immunoglobulins is important in the diagnostic and clinical monitoring of primary immunodeficiencies, monoclonal gammopathies, autoimmune diseases and others pathological conditions(X-linked agammaglobulinemia, hyper-IgM, selective IgA deficiency, deficiency of IgG subclasses, transient hypogammaglobulinemia of newborns, etc.). At primary immunodeficiencies determination of immunoglobulins has crucial diagnostic value.

A decrease in concentration may indicate various pathologies – from genetic defects synthesis of immunoglobulins to transient states associated with loss of protein by the body. The reasons for the decrease in immunoglobulin synthesis may be:

• monoclonal gammopathies,
• thermal burns,
• malignant lymphomas,
• plasmacytomas,
• Hodgkin's disease,
• kidney diseases,
• primary and secondary immunodeficiencies.

Upon initial contact with an antigen, IgM is first synthesized, then IgG. When repeated, IgG is synthesized faster and in more. IgA neutralizes viruses and bacterial toxins. Increasing concentrations indicates the presence of allergies, autoimmune processes, typical for infectious diseases . An increase in Ig of different classes is noted at different pathological situations. IgM concentration increases in acute period and during exacerbation of a chronic infection, IgG - in the stage of resolution or formation of a chronic infection, IgA - in some viral infections.

Research method: ELISA, immunoturbidimetry, immunonephelometry.

Conditions for sample collection and storage: Blood serum. Storage for no more than 24 hours at 4–8 °C. Single freezing of the sample is allowed.

Complement system- a complex of proteins that are constantly present in the blood. This is a cascade system of proteolytic enzymes capable of lysing cells, intended for the humoral protection of the body from the action of foreign agents, and is involved in the implementation of the body’s immune response. It is an important component of both innate and acquired immunity. She activated by antigen-antibody reaction and is required for antibody-mediated immune hemolysis and bacteriolysis, plays an important role in phagocytosis, opsonization, chemotaxis and immune hemolysis, and is required to enhance the effect of interaction between specific antibodies and antigen.

One of the reasons for the decrease in complement factors in the blood serum may be autoantibodies directed against complement factors. A decrease in C3 and C4 complement components is accompanied by clinical picture recurrent cutaneous hemorrhagic vasculitis and arthralgia.

The level of complement components in the blood varies widely. Hereditary deficiency of complement components or their inhibitors can lead to autoimmune disorders, repeated bacterial infections, chronic inflammatory conditions.

Complement C3 component– a central component of the system, a protein of the acute phase of inflammation. This is the most important part protective system against infections. It is formed in the liver, macrophages, fibroblasts, lymphoid tissue and skin. Due to activation of C3, histamine is released from mast cells and platelets, chemotaxis of leukocytes and the combination of antibodies with antigen, phagocytosis is supported, the permeability of the vascular walls and the contraction of smooth muscles are increased. Activation of C3 plays an important role in the development of autoimmune diseases.

Complement C4 component- 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. It is involved only in the classical pathway of complement system activation. An increase or decrease in the content of complement in the body is observed in many diseases.

Indications for the study:

• suspected congenital complement deficiency, autoimmune diseases, acute and chronic bacterial and viral infections, (especially recurrent), oncological diseases;
• dynamic observation of patients with systemic autoimmune diseases.

Decrease in C3 concentration-observed when birth defects complement, various inflammatory and infectious, autoimmune diseases, prolonged fasting, during treatment with cytostatics, ionizing radiation.

Increasing C4 concentration characteristic of an acute phase reaction, observed in autoimmune diseases, and the prescription of certain medications.

Decrease in C4 concentration– noted in congenital defects of the complement system (C4 deficiency in newborns), some autoimmune diseases, systemic vasculitis, Sjögren’s syndrome, kidney transplantation.

Circulating immune complexes in the blood (CIC)– an indicator of the development of various inflammatory processes in the body and the activity of their course. An increase in CEC is observed in acute and chronic infections, autoimmune diseases, viral hepatitis. CECs are present in many people with SLE and RA, especially in cases where there are complications such as vasculitis. There is a positive correlation between disease activity and the level of CEC in the blood. The formation of the Central Election Commission represents physiological mechanism protection leading to quick elimination either endogenous or exogenous antigens through the reticuloendothelial system. However, CECs have the ability to bind and activate complement, which leads to tissue damage. Leaving the bloodstream in small vessels, they can be deposited in tissues, in the glomeruli of the kidneys, in the lungs, skin, joints, and vessel walls. Clinically, this is often manifested by glomerulonephritis, arthritis, and neutropenia. High level CEC in blood serum and/or other biological fluids is observed in many inflammatory and malignant diseases what could become cause of pathology.

Determination of CEC in blood serum is an important marker for assessing disease activity, especially in autoimmune diseases. A decrease in the concentration of CEC during the disease or during treatment indicates the extinction of the inflammatory process and the effectiveness of therapy.

Humans have two types of immunity - cellular and humoral immunity. Both types of immunity perform different functions, but are closely related to each other. Therefore, the division of both types is relative. Humoral immunity is the ability to exclude infections due to antibodies. They are present in blood plasma, mucous membranes of the organs of vision, and saliva.

This type of immunity is developed in the womb and passes to the fetus through the placenta. Antibodies are supplied to the child during the first months of life through mother's milk. Milk protects the child from the intense influence of multiple types of microbes and microorganisms. Breastfeeding is a key factor in the development of the baby’s immune system.

The body's protective function against infectious diseases is carried out in this way: When an antigen for a specific disease is remembered. If the infection enters the body again, the antibodies recognize it and destroy the pathogenic organisms. During vaccinations, a drug is administered to subsequently recognize the antigen and absorb it.

Humoral and cellular immunity: features of functions

Cellular immunity protects against viral diseases caused by pathogenic fungi, tumors. This species directly takes part in the rejection of various foreign tissues, allergic responses and is produced by phagocytes. These cells protect the body by absorbing (phagocytosis) foreign substances, particles, and microorganisms. Granulocytes and monocytes are present in the blood to a greater extent.

The former are considered a type of leukocytes and provide the body's defenses. They are the first to notice inflammatory process.

The second type of leukocytes refers to large blood cells. Monocytes protect against viruses and infections, absorb blood clots, protect against the formation of thrombosis, and fight tumors. For immune defense the process of phagocytosis (absorption) is needed when foreign substance absorbed by phagocytes.

Both immunities cannot exist and function one without the other. Their difference lies in functionality. When humoral immunity fights directly against microorganisms, then cellular immunity fights fungus, cancer and various microbes. For normal operation 2 types of immunity are important to the immune system.

To increase protection, you should constantly take vitamins, keep healthy image life. Also, decreased immunity is characterized by constant lack of sleep and stress on the body. In the latter cases, you will need to take drugs that regulate the immune system. Immunity is one of the factors of well-being. When the functioning of the immune system is not maintained normally, all microbes and infections will constantly attack the body.

Immunity restoration

To regenerate weak immune defenses, it is initially necessary to find out the root cause of the failures. Violation of specific parts of the immune system is considered the source of certain diseases. Weak resistance of the body to infections may also indicate problems with the immune system. Treatment of diseases that reduce immunity contribute to it rapid recovery. These diseases include diabetes and chronic diseases.

Changing lifestyle is considered one of the the best ways in deciding how to increase humoral immunity.

The method covers:

• quitting smoking and alcohol;
• adherence to sleep and wakefulness;
• playing sports and walking fresh air;
• hardening of the body;
• balanced diet with vitamins.

Humoral immunity can be effectively restored by taking vitamins, traditional medicine and special medications. Any means to restore the immune system are prescribed by an immunologist in exact dosage, according to the instructions. Taking vitamins and minerals is especially beneficial in the spring. Berry fruit drinks, honey, rose hips, and aloe can restore immunity.

Adoption medicinal substances and vitamins to increase any type of immunity will not give results when the main factor in its reduction is not detected and eliminated. Pharmaceuticals prescribed by the doctor. Self-medication is prohibited.

Mechanism of humoral immunity

The basis for the implementation of humoral immunity is the mechanism of influence of substances that destroy pathogenic bacteria through the blood. Such elements are divided into groups - specific (Engerix helps) and non-specific. Conditions of a nonspecific nature include innate immune cells that suppress microorganisms.

The group includes:

• Blood serum;
• Secrets of glands that suppress the formation of bacteria;
• Lysozyme enzyme. The antibacterial agent destroys chemicals. relationships in the wall structure pathogenic organisms;
• Mucin enters the glands that secrete saliva. These are carbohydrates and proteins called glycoproteins. The unusual composition allows the main glycoproteins of mucus to protect the cell layers from the effects of toxic substances;
• Properdin is a blood serum protein from the globulin group, responsible for blood clotting;
• Cytokines are small peptide signal (control) molecules. They transmit signals between these cells. There are a couple of groups, the main one of which is interferons;
• Interferons (autogenous glycoproteins) are protein substances that have general protective properties. If the inflammatory process begins, they give a signal. In addition to this ability, they suppress pathogens. There are a number of types of autogenous glycoproteins. Alpha and Beta arise during viral infection, and Gamma is formed due to immune cells.

It is worth considering the concept of the complement system - protein complexes that perform the function of neutralizing bacteria. The complement system includes up to twenty proteins with their own serial number (C1, C2, C3 and others).

Immunology

Specific response is a single factor. For example, in childhood a child suffered from smallpox. As an adult, he will no longer suffer from this disease, since immunity has already developed. This also applies to all those vaccinations that a person received at an early age.

The nonspecific form involves multi-purpose innate protection, including the body’s response to infection entering the body.

Humoral immune response is the synthesis of antibodies by B cells in response to the appearance of pathogenic organisms in the human body. As the humoral immune response develops from the stage of antigen detection to more intense antibody production, 2 main actions occur:

• transition of antibody synthesis from one type to another;
• increasing the strength of binding of the active zones of antibodies with reactive groups of the antigen.

The place of formation is considered to be follicles with an additional membrane or places of concentration of B-lymphocytes in lymphoid tissue. Antigen detection occurs at the periphery of the follicle. A subpopulation of T lymphocytes enters the process and assists in the production of antibodies. B lymphocytes begin to divide rapidly.

Immunoglobulin genes are switched, and the number of possible mutations increases. On the plane of lymphocytes arise different types immunoglobulins of class G. B-cell clones in places of reproduction are selected based on the high degree of affinity of their receptors. Cells having increased degree affinities are differentiated into:

• plasma cells;
• cells that store information about previously active antigens.

The participation of the resulting antibodies is expressed in 3 forms:

1. reaction of neutralization of microorganisms;
2. enhanced phagocytic activity;
3. activation of a complex of complex proteins.

During their existence in the host's body, pathogens enter the extracellular environment. Presence in body fluids can be long (if we talk about extracellular pathogenic bacteria) or shorter when the body is affected by intracellular microorganisms.

During normal immune activity, infectious agents, toxic substances present outside the host cells, are exposed to the following immunoglobulins:

• An effector molecule is a small molecule whose concentration regulates the activity of a protein molecule;
• B lymphocytes are capable of producing antibodies in two forms - membrane-bound and secreted (soluble).

Why does immunity decrease?

A decrease in the functioning of the immune system has specific prerequisites that indicate health problems. They are relatively divided into a number of groups:

Wrong lifestyle:

• poor nutrition;
• a painful condition that occurs when there is insufficient intake of vitamins in the body compared to their consumption;
• a condition characterized by low hemoglobin or red blood cells in blood;
• excess or lack of physical activity;
• sleep disturbances;
• drinking alcohol, smoking;
• bad ecology;
• poisoning of the body by emissions.

Immunity may decrease due to diseases:

• pathologies of the circulatory system;
• diarrhea due to impaired absorption (impaired digestive and transport function of the small intestine);
• fast and a sharp decline kidney and liver functions;
• self-poisoning of the body with nitrogenous compounds such as urea, uric acid, creatinine and indican;
• HIV infection;
• immunodeficiencies of congenital and acquired nature;
• oncological diseases;
• long-term antibacterial treatment;
• chemotherapy;
• helminths.

There is no need to self-medicate, since increasing immunity is not an easy task. In this regard, medical supervision is needed.

Comprehensive study of humoral immunity

An immunogram is a list of characteristics that are deciphered based on the results of a blood test. In this way, you can learn about the functioning of the immune system. However, with the procedure it is impossible to know the disease factor. Finding out whether there is immunity to a specific disease will also not work.

The immune system has a complex mechanism. Therefore, characteristics are assessed not only by number, but by their compliance and dynamics. As a rule, the following characteristics are indicated in the immunogram:

• Lymphocyte count;
• T-lymphocytes (recognize the antigen and communicate to B-lymphocytes);
• Helper T cells ( main function which is to enhance the adaptive immune response);
• Natural killer cells (large granular lymphocytes that are part of the innate immune system);
• B lymphocytes (having received information, they secrete antibodies);
• The level of immunoglobulins that destroy pathogenic microorganisms;
• Marker of cell death.

Foreign elements captured by antibodies that should soon dissolve. When a very large number of them accumulate, this is a criterion for autoimmune diseases. That is, the body does not recognize its cells and forms antibodies to attack ( increased level blood sugar, damage to the myelin sheath nerve fibers head and spinal cord., inflammatory disease connective tissue joints).

Content:

What is humoral immunity

Humoral immunity is the body's defense system, provided by substances in the intercellular environment (antibodies, gland secretions, enzymes). In the traditional classification of immunity, it is contrasted with cellular immunity, however, such a division is arbitrary, since the work of these mechanisms is closely related.

Principles of functioning of humoral immunity

Humoral immunity requires the presence of substances from two categories:

1. Nonspecific immunity factors are chemical compounds, suppressing the development of bacteria and viruses. These include blood plasma proteins (interferons, markers), secretions endocrine glands, some enzymes (lysozyme).
2. Specific immunity factors are represented by antibodies. They are produced by white blood cells B lymphocytes and respond to certain antigens– potentially dangerous foreign substances and agents.

Everything is biological active substances work in close conjunction with blood cells responsible for protecting the human body from pathogenic organisms.

Video: Program “Live Healthy!” about the humoral type of immune response

Pathways for the formation of antibodies in the human body

Some of the antibodies enter the child’s body from the mother during intrauterine development. They belong to those that were created in the process of human evolution. Another group of factors reaches the baby after birth through breast milk.

Independent production of antibodies by the human body occurs when it encounters new antigens (for example, during diseases) and occurs unevenly. On the first day their number is insignificant, then it increases in waves with a peak on the 4th day, after which it also gradually decreases.

Injection of ready-made antibodies is possible in case of urgent need during illness. The decision to carry out such a procedure is made by the attending physician based on test data and an assessment of the severity of the patient’s condition.

The body is able to remember antigens. In this case, when they hit them again, he quickly copes with the disease. It is this feature that makes possible use vaccines.

Disturbances in the mechanism of the humoral immune response

The performance of humoral immunity affects two groups of pathologies:

1. Violations of the function of this type of immunity directly are caused by congenital pathologies mechanisms for the production of immunoglobulin proteins lead to the development of syndromes characterized by increased sensitivity to certain microorganisms or insufficient activity of the glands.
2. Malfunctions of the immune system general include defective lymphocyte syndrome, malformations and formation of tissues of the immune system.

Improper or insufficient functioning of the immune system can lead to the development serious illnesses: various types allergies, Crohn's disease, atopic dermatitis, colitis, systemic lupus erythematosus, rheumatoid arthritis. The study of the functioning of the immune system is assessed using an immunogram. It is an extensive blood test that determines a number of indicators of the composition and activity of lymphocytes.

Indicators of humoral immunity

To assess the performance of the humoral component of the immune response, data demonstrating the content of antibodies in the blood serum are used.

Blood counts

Characteristics of antibodies include a description of their role in the work protective forces body, production time and other properties that allow the use of immunogram data to make a diagnosis and develop a treatment regimen:

Each type of immunoglobulin plays a role in ensuring the body’s complex response to infection.

Symptoms of weakened humoral immunity

TO external manifestations Immune deficiencies include:

A decrease in the effectiveness of the body's defenses is expressed in general symptoms. Close connection in the work of cellular and humoral mechanisms makes it difficult to describe these signs separately for each of them.

Principles of restoring the functioning of the immune system

To activate the weakened defenses of the body, it is important to determine the cause of failures in their work. Damage to certain parts of the immune system can lead to specific diseases with specific symptoms or be expressed in general decline quality of health and level of resistance to infectious diseases.

Compensation or treatment of diseases that negatively affect the functioning of humoral immunity automatically contributes to its speedy recovery without taking additional measures. Such pathologies include diabetes mellitus and some chronic diseases.

Lifestyle correction is also necessary to address the issue of improving the performance of the immune system. It includes:

• getting rid of bad habits;
• adherence to sleep and wakefulness, rest and work;
• high motor activity and daily exposure to fresh air;
• healthy diet.

Humoral immunity can also be effectively restored through the use of vitamin-mineral complexes, traditional medicine recipes and specialized drugs. Complex vitamins and microelements must be consumed according to instructions, avoiding overdose. The course of admission is especially useful in the spring period of the year.

Fruit drinks made from sour northern berries, honey, ginger, rose hips, hawthorn, aloe and other products serve as adaptogens and antiseptics mild action. Tinctures of propolis, echinacea, rhodiola rosea, ginseng are effective means natural origin to restore the body's defenses.

Warning: Taking medications and vitamin-mineral complexes to boost any type of immunity will not be effective if the cause of the disruption in its functioning is not found and eliminated.

Immunomodulator medications should be taken as prescribed by a doctor.