Phagocytosis is the main mechanism of the immune system. Cells capable of phagocytosis include Human anatomy name capable of phagocytosis
Indicate the organisms whose cells are capable of phagocytosis:
a) bacteria;
b) mushrooms; c) plants; d) animals.
3. Name the organisms that make up cell membrane which includes glycoca-
liks:
a) bacteria; b) mushrooms; c) plants; d) animals.
4. Indicate the compounds that mainly make up chromosomes:
a) proteins and
lipids; b) proteins and DNA; c) proteins and RNA; d) lipids and RNA.
5. Name the scientist who proposed the term “cell”:
a) R. Hooke;
b) T. Schwann; c) M. Schleiden; d) R. Virchow.
CHOOSE TWO CORRECT ANSWERS FROM THE SUGGESTED ANSWERS
1. Name the organisms whose cells have vegetative and generative
kernels:
a) yeast; b) ulotrix; c) foraminifera; d) ciliates.
2. Name the cells that do not have nuclei:
a) erythrocytes of most mammals
feeding; b) epithelial cells; c) leukocytes; d) mammalian platelets.
3. Name the organisms whose cells have a nucleus:
a) cyanobacteria; b) penalty
cill; c) mucor; d) Escherichia coli.
4. Name the structures located inside the nucleus:
a) ribosomal subunits;
b) chromatin threads; c) plastids; d) mitochondria.
5. Name the mechanisms of passive transport of substances into the cell:
a) diffusion;
b) changes in the spatial structure of proteins penetrating the membrane;
c) potassium-sodium pump; d) phagocytosis.
6. Name the properties of the plasma membrane:
a) semi-permeability; b) spo-
the ability to self-renewal; c) rigidity; d) the ability to synthesize one’s own
natural proteins.
COMPLIANCE TASKS
1. Determine whether chromosomes belong to one or another type.
Types of chromosomes Names of chromosomes
A) Similar in size and structure
B) They differ in size and structure
B) Sexual
D) Non-sexual
1 Heterochromosomes
2 Autosomes
3 Polytene
4 Homologous
5 Non-homologous
2. Determine the correspondence of organelles and cell structures to groups of organisms,
in which they are presented.
Groups of organisms Organelles and structures
A) Red blood cells of most mammals
B) Cyanobacteria
B) Plant skin cells
D) Ciliate cells
1 Nuclei are not differentiated
into vegetative and generative
2 Absence of a nucleus in mature cells
3 Nucleoid
4 Vegetative and generative nuclei
5 Sieve plates
3. Establish a correspondence between the names of scientists and their contribution to development
cytology.
Surnames of scientists Contribution to the development of cytology
A) R. Hooke
B)A. van Leeuwenhoek
B) T. Schwann
G)I. Mechnikov
1 Discovered the phenomenon of phagocytosis
2 Discovered the phenomenon of pinocytosis
3 Proposed the term "cell"
4 Discovered and described bacterial cells
5 Lay the foundations cell theory
ADVANCED QUESTIONS
1. How does the absence of a nucleus affect the properties of a cell? Justify your answer.
2. How can one explain the fact that some eukaryotic cells lacking a core?
Give examples of such cells.
3. What is the significance of the study of karyotypes of organisms for taxonomy? Answer
justify.
4. What are the similarities and differences between the hereditary material of prokaryotic cells and
eukaryotes?
5. What are the similarities and differences between the processes of pinocytosis and phagocytosis? Cells
what organisms can carry out these processes?
6. What is the relationship between the entry of water into the cell and its maintenance?
forms? Justify your answer
The protective role of mobile blood cells and tissues was first discovered by I. I. Mechnikov in 1883. He called these cells phagocytes and formulated the basic principles of the phagocytic theory of immunity. Phagocytosis- absorption of large macromolecular complexes or corpuscles and bacteria by the phagocyte. Phagocyte cells: neutrophils and monocytes/macrophages. Eosinophils can also phagocytose (they are most effective in anthelmintic immunity). The process of phagocytosis is enhanced by opsonins that envelop the object of phagocytosis. Monocytes make up 5-10%, and neutrophils 60-70% of blood leukocytes. Entering the tissue, monocytes form a population of tissue macrophages: Kupffer cells (or stellate reticuloendotheliocytes of the liver), microglia of the central nervous system, osteoclasts of bone tissue, alveolar and interstitial macrophages).
Process of phagocytosis. Phagocytes move directionally to the object of phagocytosis, reacting to chemoattractants: microbial substances, activated complement components (C5a, C3a) and cytokines.
The phagocyte plasmalemma envelops bacteria or other corpuscles and its own damaged cells. Then the object of phagocytosis is surrounded by the plasmalemma and the membrane vesicle (phagosome) is immersed in the cytoplasm of the phagocyte. The phagosome membrane merges with the lysosome and the phagocytosed microbe is destroyed, the pH acidifies to 4.5; Lysosome enzymes are activated. The phagocytosed microbe is destroyed under the action of lysosome enzymes, cationic defensin proteins, cathepsin G, lysozyme and other factors. During an oxidative (respiratory) explosion, toxic antimicrobial forms of oxygen are formed in the phagocyte - hydrogen peroxide H 2 O 2, superoxidation O 2 -, hydroxyl radical OH -, singlet oxygen. In addition, nitric oxide and the NO - radical have an antimicrobial effect.
Macrophages perform protective function even before interaction with other immunocompetent cells (nonspecific resistance). Macrophage activation occurs after the destruction of the phagocytosed microbe, its processing (processing) and presentation (presentation) of the antigen to T-lymphocytes. In the final stage of the immune response, T lymphocytes release cytokines that activate macrophages (acquired immunity). Activated macrophages, together with antibodies and activated complement (C3b), carry out more efficient phagocytosis ( immune phagocytosis), destroying phagocytosed microbes.
Phagocytosis can be complete, ending with the death of the captured microbe, or incomplete, in which the microbes do not die. An example of incomplete phagocytosis is phagocytosis of gonococci, tubercle bacilli and leishmania.
All phagocytic cells of the body, according to I. I. Mechnikov, are divided into macrophages and microphages. Microphages include polymorphonuclear blood granulocytes: neutrophils, eosinophils and basophils. Macrophages of various tissues of the body ( connective tissue, liver, lungs, etc.) together with blood monocytes and their bone marrow precursors (promonocytes and monoblasts) are combined into a special system of mononuclear phagocytes (MPF). The SMF is phylogenetically more ancient than the immune system. It is formed quite early in ontogenesis and has certain age-related characteristics.
Microphages and macrophages have a common myeloid origin - from a pluripotent stem cell, which is a single precursor of granulo- and monocytopoiesis. Peripheral blood contains more granulocytes (60 to 70% of all blood leukocytes) than monocytes (1 to 6%). At the same time, the duration of circulation of monocytes in the blood is much longer (half-life 22 hours) than that of short-lived granulocytes (half-life 6.5 hours). Unlike blood granulocytes, which are mature cells, monocytes, leaving the bloodstream, mature into tissue macrophages in the appropriate microenvironment. The extravascular pool of mononuclear phagocytes is tens of times greater than their number in the blood. The liver, spleen, and lungs are especially rich in them.
All phagocytic cells are characterized by common basic functions, similarity of structures and metabolic processes. Outdoor plasma membrane of all phagocytes is an actively functioning structure. It is characterized by pronounced folding and carries many specific receptors and antigenic markers, which are constantly updated. Phagocytes are equipped with a highly developed lysosomal apparatus, which contains a rich arsenal of enzymes. The active participation of lysosomes in the functions of phagocytes is ensured by the ability of their membranes to merge with the membranes of phagosomes or with the outer membrane. IN the latter case Cell degranulation occurs and concomitant secretion of lysosomal enzymes into the extracellular space.
Phagocytes have three functions:
1 - protective, associated with cleansing the body of infectious agents, tissue breakdown products, etc.;
2 - presenting, consisting in the presentation of antigenic epitopes on the phagocyte membrane;
3 - secretory, associated with the secretion of lysosomal enzymes and other biological active substances- monokin playing important role in immunogenesis.
Fig 1. Functions of a macrophage.
In accordance with the listed functions, the following sequential stages of phagocytosis are distinguished.
1. Chemotaxis - targeted movement of phagocytes in the direction of a chemical gradient of chemoattractants in the environment. The ability for chemotaxis is associated with the presence on the membrane of specific receptors for chemoattractants, which can be bacterial components, products of degradation of body tissues, activated fractions of the complement system - C5a, C3a, products of lymphocytes - lymphokines.
2. Adhesion (attachment) is also mediated by the corresponding receptors, but can proceed in accordance with the laws of nonspecific physicochemical interaction. Adhesion immediately precedes endocytosis (uptake).
3. Endocytosis is basic physiological function so-called professional phagocytes. There are phagocytosis - in relation to particles with a diameter of at least 0.1 microns and pinocytosis - in relation to smaller particles and molecules. Phagocytic cells are capable of capturing inert particles of coal, carmine, latex, flowing around them with pseudopodia without the participation of specific receptors. At the same time, phagocytosis of many bacteria, yeast-like fungi of the genus Candida and other microorganisms is mediated by special mannose fucose receptors of phagocytes, which recognize the carbohydrate components of the surface structures of microorganisms. The most effective is receptor-mediated phagocytosis for the Fc fragment of immunoglobulins and for the C3 fraction of complement. This phagocytosis is called immune, since it occurs with the participation of specific antibodies and the activated complement system, which opsonize the microorganism. This makes the cell highly susceptible to engulfment by phagocytes and leads to subsequent intracellular death and degradation. As a result of endocytosis, a phagocytic vacuole is formed - a phagosome. It should be emphasized that the endocytosis of microorganisms largely depends on their pathogenicity. Only avirulent or low-virulent bacteria (non-capsular strains of pneumococcus, strains of streptococcus, devoid of hyaluronic acid and M-protein) are phagocytosed directly. Most bacteria endowed with aggressive factors (staphylococci - A-protein, E. coli - expressed capsular antigen, salmonella - Vi-antigen, etc.) are phagocytosed only after they are opsonized by complement and/or antibodies.
The presentation, or representing, function of macrophages is to fix antigenic epitopes of microorganisms on the outer membrane. In this form they are presented by macrophages for their specific recognition by cells immune system- T-lymphocytes.
Secretory function consists in the secretion of biologically active substances - monokines by mononuclear phagocytes. These include substances that have a regulating effect on the proliferation, differentiation and functions of phagocytes, lymphocytes, fibroblasts and other cells. A special place among them is occupied by interleukin-1 (IL-1), which is secreted by macrophages. It activates many functions of T lymphocytes, including the production of the lymphokine interleukin-2 (IL-2). IL-1 and IL-2 are cellular mediators involved in the regulation of immunogenesis and different forms immune response. At the same time, IL-1 has the properties of an endogenous pyrogen, since it induces fever by acting on the nuclei of the anterior hypothalamus. Macrophages produce and secrete such important regulatory factors as prostaglandins, leukotrienes, cyclic nucleotides with wide range biological activity.
Along with this, phagocytes synthesize and secrete a number of products with predominantly effector activity: antibacterial, antiviral and cytotoxic. These include oxygen radicals (O 2, H 2 O 2), complement components, lysozyme and other lysosomal enzymes, interferon. Due to these factors, phagocytes can kill bacteria not only in phagolysosomes, but also outside cells, in the immediate microenvironment. These secretory products can also mediate the cytotoxic effect of phagocytes on various target cells in cell-mediated immune reactions, for example, in a delayed-type hypersensitivity reaction (DTH), in homograft rejection, and in antitumor immunity.
The considered functions of phagocytic cells ensure their active participation in maintaining the homeostasis of the body, in the processes of inflammation and regeneration, in nonspecific anti-infective defense, as well as in immunogenesis and specific reactions. cellular immunity(HRT). The early involvement of phagocytic cells (first granulocytes, then macrophages) in the response to any infection or any damage is explained by the fact that microorganisms, their components, tissue necrosis products, blood serum proteins, substances secreted by other cells are chemoattractants for phagocytes. At the site of inflammation, the functions of phagocytes are activated. Macrophages replace microphages. In cases where inflammatory reaction with the participation of phagocytes is not enough to cleanse the body of pathogens, then the secretory products of macrophages ensure the involvement of lymphocytes and the induction of a specific immune response.
Complement system. The complement system is a multicomponent self-assembled system of serum proteins that plays an important role in maintaining homeostasis. It is capable of being activated during the process of self-assembly, i.e., the sequential attachment of individual proteins, which are called components or complement fractions, to the resulting complex. Nine such factions are known. They are produced by liver cells, mononuclear phagocytes and are contained in the blood serum in an inactive state. The process of complement activation can be triggered (initiated) in two different ways, called classical and alternative.
When complement is activated in the classical way, the initiating factor is the antigen-antibody complex (immune complex). Moreover, antibodies of only two classes IgG and IgM in the composition of immune complexes can initiate complement activation due to the presence in the structure of their Fc fragments of sites that bind the C1 fraction of complement. When C1 joins the antigen-antibody complex, an enzyme (C1-esterase) is formed, under the action of which an enzymatically active complex (C4b, C2a) is formed, called C3-convertase. This enzyme breaks down S3 into S3 and S3b. When subfraction C3b interacts with C4 and C2, a peptidase is formed that acts on C5. If the initiating immune complex is associated with the cell membrane, then the self-assembling complex C1, C4, C2, C3 ensures the fixation of the activated fraction C5, and then C6 and C7, on it. The last three components jointly contribute to the fixation of C8 and C9. In this case, two sets of complement fractions - C5a, C6, C7, C8 and C9 - constitute a membrane attack complex, after which it joins cell membrane the cell is lysed due to irreversible damage to the structure of its membrane. In the event that complement activation along the classical pathway occurs with the participation of the erythrocyte-antierythrocyte Ig immune complex, hemolysis of erythrocytes occurs; If the immune complex consists of a bacterium and an antibacterial Ig, lysis of the bacteria occurs (bacteriolysis).
Thus, when activating complement in the classical way, the key components are C1 and C3, the cleavage product of which C3b activates the terminal components of the membrane attack complex (C5 - C9).
There is a possibility of activation of S3 with the formation of S3b with the participation of S3 convertase of the alternative pathway, i.e., bypassing the first three components: C1, C4 and C2. The peculiarity of the alternative pathway of complement activation is that initiation can occur without the participation of the antigen-antibody complex due to polysaccharides of bacterial origin - lipopolysaccharide (LPS) cell wall gram-negative bacteria, surface structures of viruses, immune complexes, including IgA and IgE.
He conducted his research in Italy, on the shores of the Strait of Messina. The scientist was interested in whether individual multicellular organisms retained the ability to capture and digest food, as single-celled organisms, such as amoebas, do. After all, as a rule, in multicellular organisms, food is digested in the digestive canal and ready-made nutrient solutions are absorbed. observed starfish larvae. They are transparent and their contents are clearly visible. These larvae do not have a circulating larvae, but have wandering ones throughout the larva. They captured particles of red carmine dye introduced into the larva. But if these absorb paint, then maybe they capture any foreign particles? Indeed, the rose thorns inserted into the larva turned out to be surrounded and painted with carmine.
They were able to capture and digest any foreign particles, including pathogenic microbes. called wandering phagocytes (from the Greek words phages - devourer and kytos - container, here -). And the process of capturing and digesting different particles by them is phagocytosis. Later he observed phagocytosis in crustaceans, frogs, turtles, lizards, as well as in mammals - guinea pigs, rabbits, rats and humans.
Phagocytes are special. They need digestion of captured particles not for nutrition, like amoebas and other single-celled organisms, but to protect the body. In starfish larvae, phagocytes wander throughout the body, and in higher animals and humans they circulate in the vessels. These are one of the types of white blood cells, or leukocytes, called neutrophils. It is they, attracted by the toxic substances of microbes, that move to the site of infection (see). Having emerged from the vessels, such leukocytes have outgrowths - pseudopods, or pseudopodia, with the help of which they move in the same way as amoeba and wandering starfish larvae. Such leukocytes capable of phagocytosis were called microphages.
However, not only constantly moving leukocytes, but also some sedentary ones can become phagocytes (now they are all combined into unified system phagocytic mononuclear cells). Some of them rush to dangerous areas, for example, to the site of inflammation, while others remain in their usual places. Both are united by the ability to phagocytose. These tissue (histocytes, monocytes, reticular and endothelial) are almost twice as large as microphages - their diameter is 12-20 microns. That's why I called them macrophages. There are especially many of them in the spleen, liver, lymph nodes, bone marrow and in the walls of blood vessels.
Microphages and wandering macrophages themselves actively attack “enemies,” and stationary macrophages wait for the “enemy” to swim past them in the current or lymph. Phagocytes “hunt” for microbes in the body. It happens that in an unequal struggle with them they find themselves defeated. Pus is an accumulation of dead phagocytes. Other phagocytes will approach it and begin to eliminate it, as they do with all sorts of foreign particles.
Phagocytes clear constantly dying cells and participate in various changes in the body. For example, when a tadpole transforms into a frog, when, along with other changes, the tail gradually disappears, entire hordes of phagocytes destroy the tadpole’s tail.
How do particles get inside the phagocyte? It turns out that with the help of pseudopodia, which grab them, like an excavator bucket. Gradually the pseudopodia lengthen and then close over foreign body. Sometimes it seems to be pressed into the phagocyte.
He assumed that phagocytes should contain special substances that digest microbes and other particles captured by them. Indeed, such particles were discovered 70 years after the discovery of phagocytosis. They contain substances capable of breaking down large organic molecules.
It has now been found that, in addition to phagocytosis, they primarily participate in the neutralization of foreign substances (see). But for the process of their production to begin, the participation of macrophages is necessary. They capture foreign
Cells capable of phagocytosis include:
Polymorphonuclear leukocytes (neutrophils, eosinophils, basophils)
Monocytes
Fixed macrophages (alveolar, peritoneal, Kupffer, dendritic cells, Langerhans
2. What type of immunity provides protection for the mucous membranes communicating with external environment. and skin from penetration of the pathogen into the body: specific local immunity
3. K central authorities immune system include:
Bone marrow
Bursa of Fabricius and its analogue in humans (Peyre's patches)
4. What cells produce antibodies:
A. T-lymphocyte
B. B-lymphocyte
B. Plasma cells
5. Haptens are:
Simple organic compounds with low molecular weight (peptides, disaccharides, NK, lipids, etc.)
Unable to induce antibody formation
Capable of specifically interacting with those antibodies in the induction of which they participated (after attaching to a protein and transforming into full-fledged antigens)
6. Penetration of the pathogen through the mucous membrane is prevented by class immunoglobulins:
A.IgA
B. SIgA
7. The function of adhesins in bacteria is performed by:cell wall structures (fimbriae, proteins outer membrane, LPS)
U Gr(-): associated with pili, capsule, capsule-like membrane, outer membrane proteins
U Gr(+): teichoic and lipoteichoic acids of the cell wall
8. Delayed hypersensitivity is caused by:
Sensitized T-lymphocyte cells (lymphocytes that have undergone immunological “training” in the thymus)
9. Cells that carry out a specific immune response include:
T lymphocytes
B lymphocytes
Plasma cells
10. Components required for the agglutination reaction:
microbial cells, latex particles (agglutinogens)
saline
antibodies (agglutinins)
11. The components for staging the precipitation reaction are:
A. Cell suspension
B. Antigen solution (hapten in physiological solution)
B. Heated microbial cell culture
G. Complement
D. Immune serum or test serum of the patient
12. What components are necessary for the complement fixation reaction:
Saline
complement
patient's blood serum
sheep red blood cells
hemolytic serum
13 Components required for the immune lysis reaction:
A .Live cell culture
B.Dead cells
IN .Complement
G .Immune serum
D. Saline solution
14. U healthy person in peripheral blood the number of T-lymphocytes is:
B.40-70%
15. Drugs used for emergency prevention and treatment:
A. Vaccines
B. Serums
B. Immunoglobulins
16. The method for quantitative assessment of human peripheral blood T-lymphocytes is the reaction:
A. Phagocytosis
B. Complement fixation
B. Spontaneous rosette formation with sheep erythrocytes (E-ROC)
G. Rosette formations with mouse erythrocytes
D. Rosette formations with erythrocytes treated with antibodies and complement (EAS-ROK )
17. When mouse erythrocytes are mixed with human peripheral blood lymphocytes, “E-rosettes” are formed with those cells that are:
A. B-lymphocytes
B. Undifferentiated lymphocytes
B. T-lymphocytes
18. To perform the latex agglutination reaction, you must use all of the following ingredients, except:
A. Patient’s blood serum diluted 1:25
B. Alcohol
31. If an infectious disease is transmitted to a person from a sick animal, it is called:
A. anthroponotic
B. zooanthroponotic
32. Basic properties and signs of a full-fledged antigen:
A. is a protein
B. is a low molecular weight polysaccharide
G. is a high molecular weight compound
D. causes the formation of antibodies in the body
E. does not cause the formation of antibodies in the body
Z. insoluble in body fluids
I. is able to react with a specific antibody
K. is not able to react with a specific antibody
33. Nonspecific resistance of a macroorganism includes all of the following factors, except:
A. phagocytes
B. gastric juice
B. antibodies
G. lysozyme
E. temperature reaction
G. mucous membranes
Z. lymph nodes
I. interferon
K. complement system
L. properdin
Z, toxoid
49. What bacteriological preparations are prepared from bacterial toxins:
Prevention toxoids
Diagnostic toxin
50. What ingredients are needed to prepare a killed vaccine:
Highly virulent and highly immunogenic strain of microorganism (whole killed bacterial cells)
Heating at t=56-58C for 1 hour
Addition of formaldehyde
Adding phenol
Adding alcohol
Exposure to ultraviolet rays
Ultrasonic treatment
! 51. Which of the following bacterial preparations are used to treat infectious diseases:
A. live vaccine
B. toxoid
B. immunoglobulin
G. antitoxic serum
D. diagnosticum
E. bacteriophage
G. allergen
H. agglutinating serum
I. killed vaccine
K. precipitating serum
52. For what immune reactions are diagnosticums used:
Expanded agglutination reaction of the Vidal type
Passive reactions, or indirect hemagglutination(RNGA )
53. Duration of the protective effect of immune sera introduced into the human body: 2-4weeks
54. Methods of introducing the vaccine into the body:
intradermally
subcutaneously
intramuscularly
intranasally
orally (enterally)
through mucous membranes respiratory tract using artificial aerosols of live or killed vaccines
55. Main properties of bacterial endotoxins:
A. are proteins(cell wall of Gr(-) bacteria)
B. consist of lipopolysaccharide complexes
? V. are firmly associated with the body of the bacterium
G. are easily released from bacteria into the environment
D. thermostable
E. thermolabile
G. highly toxic
Z. moderately toxic
I. are capable of turning into toxoid under the influence of formalin and temperature
K. causes the formation of antitoxins
56. The occurrence of an infectious disease depends on:
A. forms of bacteria
B. reactivity of the microorganism
B. Gram staining ability
D. dose of infection
D. degree of pathogenicity of the bacterium
E. portal of entry infection
G. states of cardio-vascular system microorganism
Z. states environment (atmospheric pressure, humidity, solar radiation, temperature, etc.)
57. MHC (major histocompatibility complex) antigens are located on the membranes:
A. nucleated cells of different microorganism tissues (leukocytes, macrophages, histiocytes, etc.)
B. red blood cells
B. only leukocytes
58. The ability of bacteria to secrete exotoxins is due to:
A. form of bacteria
B. availability
tox
-gene
B. ability to form capsules
? 59. The main properties of pathogenic bacteria are:
A. the ability to cause an infectious process
B. ability to form spores
B. specificity of action on the macroorganism
G. thermal stability
D. virulence
E. ability to form toxins
G. invasiveness
H. ability to form sugars
I. ability to form capsules
K. organotropy
60. Methods for assessing a person’s immune status are:
A. agglutination reaction
B. phagocytosis reaction
B. ring precipitation reaction
G. radial immunodiffusion according to Mancini
D. immunofluorescence test with monoclonal antibodies to identify T-helpers and T-suppressors
E. complement fixation reaction
G. method of spontaneous rosette formation with sheep erythrocytes (E-ROK)
61. Immunological tolerance is:
A. ability to produce antibodies
B. the ability to cause proliferation of a specific cell clone
B. lack of immunological response to antigen
62. Inactivated blood serum:
Serum subjected to heat treatment at 56C for 30 minutes, which led to the destruction of complement
63. Cells that suppress the immune response and participate in the phenomenon of immunotolerance are:
A. T helper cells
B. red blood cells
B. lymphocytes T-suppressors
D. lymphocytes T-effectors
D. lymphocytes T killers
64. The functions of T-helper cells are:
Necessary for the transformation of B lymphocytes into antibody-forming cells and memory cells
Recognize cells having MHC class 2 antigens (macrophages, B lymphocytes)
Regulates the immune response
65. Mechanism of precipitation reaction:
A. formation of an immune complex on cells
B. toxin inactivation
B. formation of a visible complex when an antigen solution is added to serum
D. Glow of the antigen-antibody complex in ultraviolet rays
66. The division of lymphocytes into T and B populations is due to:
A. the presence of certain receptors on the surface of cells
B. site of proliferation and differentiation of lymphocytes (bone marrow, thymus)
B. the ability to produce immunoglobulins
D. presence of the HGA complex
D. the ability to phagocytose antigen
67. Aggression enzymes include:
Protease (destroys antibodies)
Coagulase (clotts blood plasma)
Hemolysin (destroys the membranes of red blood cells)
Fibrinolysin (dissolution of fibrin clot)
Lecithinase (acts on lecithin )
68. Class immunoglobulins pass through the placenta:
A .Ig G
69.Protection against diphtheria, botulism, and tetanus is determined by immunity:
A. local
B. antimicrobial
B. antitoxic
G. congenital
70. The reaction of indirect hemagglutination involves:
A. erythrocyte antigens participate in the reaction
B. the reaction involves antigens sorbed on erythrocytes
B. the reaction involves receptors for adhesins of the pathogen
71. For sepsis:
A. blood is a mechanical carrier of the pathogen
B. the pathogen multiplies in the blood
B. the pathogen enters the blood from purulent foci
72. Intradermal test to detect antitoxic immunity:
The Schick test with diphtheria toxin is positive if there are no antibodies in the body that can neutralize the toxin
73. Mancini’s immunodiffusion reaction refers to a type reaction:
A. agglutination reaction
B. lysis reaction
B. precipitation reaction
D. ELISA (enzyme-linked immunosorbent assay)
E. phagocytosis reaction
G. RIF (immunofluorescence reaction )
74. Reinfection is:
A. a disease that develops after recovery from repeated infection with the same pathogen
B. a disease that developed during infection with the same pathogen before recovery
B. return of clinical manifestations
75. Visible result positive reaction according to Mancini is:
A. formation of agglutinins
B. turbidity of the medium
B. cell dissolution
D. formation of precipitation rings in the gel
76. Human resistance to the causative agent of chicken cholera determines immunity:
A. acquired
B. active
B. passive
G. post-infectious
D. species
77. Immunity is maintained only in the presence of a pathogen:
A. active
B. passive
V. congenital
G. sterile
D. infectious
78. The latex agglutination reaction cannot be used for the following purposes:
A. identification of the pathogen
B. determination of immunoglobulin classes
B. detection of antibodies
79. Rosette formation reaction with sheep erythrocytes (E-ROC) is considered
positive if one lymphocyte adsorbs:
A. one sheep red blood cell
B. complement fraction
B. more than 2 sheep red blood cells (more than 10)
G. bacterial antigen
? 80. Incomplete phagocytosis is observed in diseases:
A. syphilis
B. brucellosis
V. tuberculosis
G. dysentery
D. meningitis
E. leprosy
G. gonorrhea
Z. typhoid fever
I. cholera
TO. anthrax
? 81. Specific and non-specific factors humoral immunity are:
A. red blood cells
B. leukocytes
B. lymphocytes
G. platelets
D. immunoglobulins
E. complement system
J. properdin
Z. albumin
I. leukins
K. lysines
L. erythrin
lysozyme
82. When sheep erythrocytes are mixed with human peripheral blood lymphocytes, E-rosettes are formed only with those cells that are:
A. B-lymphocytes
B. undifferentiated
B. T-lymphocytes
83. The results of the latex agglutination reaction are recorded in:
A. in milliliters
B. in millimeters
V. in grams
G. in the pros
84. Precipitation reactions include:
B. flocculation reaction (according to Korotyaev)
B. phenomenon of Isaev Pfeiffer
G. precipitation reaction in gel
D. agglutination reaction
E. bacteriolysis reaction
G. hemolysis reaction
H. Ascoli ring-reception reaction
I. Mantoux reaction
K. radial immunodiffusion reaction according to Mancini
? 85. Main features and properties of hapten:
A. is a protein
B. is a polysaccharide
B. is a lipid
G. has a colloidal structure
D. is a high molecular weight compound
E. when introduced into the body, it causes the formation of antibodies
G. when introduced into the body does not cause the formation of antibodies
Z. soluble in body fluids
I. is able to react with specific antibodies
K. is not able to react with specific antibodies
86. Main features and properties of antibodies:
A. are polysaccharides
B. are albumins
V. are immunoglobulins
G. are formed in response to the introduction of a full-fledged antigen into the body
D. are formed in the body in response to the introduction of hapten
E. are capable of interacting with a full-fledged antigen
G. are capable of interacting with hapten
87. Necessary components for staging a detailed Gruber-type agglutination reaction:
A. patient’s blood serum
B. saline solution
B. pure culture of bacteria
D. known immune serum, non-adsorbed
D. red blood cell suspension
E. diagnosticum
G. complement
H. known immune serum, adsorbed
I. monoreceptor serum
88. Signs of a positive Gruber reaction:
G.20-24h
89. Necessary ingredients for performing a detailed Widal agglutination reaction:
Diagnosticum (suspension of killed bacteria)
Patient's blood serum
Saline
90. Antibodies that enhance phagocytosis:
A. agglutinins
B. procytinins
B. opsonins
D. complement-fixing antibodies
D. homolysins
E. optitoxins
G. bacteriotropins
Z. lysines
91. Components of the ring precipitation reaction:
A. saline solution
B. precipitating serum
B. suspension of red blood cells
D. pure culture of bacteria
D. diagnosticum
E. complement
J. precipitinogen
H. bacterial toxins
? 92. To detect agglutinins in the patient’s blood serum, the following are used:
A. extensive Gruber agglutination reaction
B. bacteriolysis reaction
B. extended Vidal agglutination reaction
D. precipitation reaction
D. reaction passive hemagglutination with erythrocyte diagonisticum
E. indicative agglutination reaction on glass
93. Lysis reactions are:
A. precipitation reaction
B. Isaev-Pfeiffer phenomenon
B. Mantoux reaction
G. Gruber agglutination reaction
D. hemolysis reaction
E. Widal agglutination reaction
G. bacteriolysis reaction
H. RSC reaction
94. Signs of a positive ring precipitation reaction:
A. turbidity of the liquid in a test tube
B. loss of bacterial motility
B. appearance of sediment at the bottom of the test tube
D. appearance of a cloudy ring
D. formation of varnish blood
E. the appearance of white lines of turbidity in the agar ("uson")
95. Time for final accounting of the Grubber agglutination reaction:
G.20-24h
96. To set up the bacteriolysis reaction it is necessary:
B. distilled water
B. immune serum (antibodies )
D. saline solution
D. red blood cell suspension
E. pure culture of bacteria
G. suspension of phagocytes
Z. complement
I. bacterial toxins
K. monoreceptor agglutinating serum
97. For prevention infectious diseases apply:
A. live vaccine
B. immunoglobulin
V. diagnosticum
G. killed vaccine
D. allergen
E. antitoxic serum
G. bacteriophage
Z. toxoid
I. chemical vaccine
K. agglutinating serum
98. After past illness is being produced next view immunity:
A. species
B. acquired natural active
B. acquired artificial active
G. acquired natural passive
D. acquired artificial passive
99. After the administration of immune serum, the following type of immunity is formed:
A. species
B. acquired natural active
B. acquired natural passive
G. acquired artificial active
D. acquired artificial passive
100. Time for final recording of the results of the lysis reaction performed in a test tube:
B.15-20min
101.Number of phases of the complement fixation reaction (CRR):
B. two
G. four
D. more than ten
102. Signs of a positive hemolysis reaction:
A. precipitation of red blood cells
B. formation of varnish blood
B. agglutination of red blood cells
D. appearance of a cloudy ring
D. turbidity of the liquid in a test tube
103. For passive immunization the following are used:
A. vaccine
B. antitoxic serum
V. diagnosticum
D. immunoglobulin
E. toxin
G. allergen
104. The ingredients necessary for staging the RSC are:
A. distilled water
B. saline solution
B. complement
D. patient's blood serum
D. antigen
E. bacterial toxins
G. sheep red blood cells
Z. toxoid
I. hemolytic serum
105. For the diagnosis of infectious diseases the following are used:
A. vaccine
B. allergen
B. antitoxic serum
G. toxoid
D. bacteriophage
E. diagnosticum
G. agglutinating serum
Z. immunoglobulin
I. precipitating serum
K. toxin
106. Bacteriological preparations are prepared from microbial cells and their toxins:
A. toxoid
B. antitoxic immune serum
B. antimicrobial immune serum
G. vaccines
D. immunoglobulin
E. allergen
G. diagnosticum
Z. bacteriophage
107. Antitoxic serums are the following:
A. anticholera
B. antibotulinum
G. antimeasles
D. against gas gangrene
E. antitetanus
G. antidiphtheria
K. against tick-borne encephalitis
108. Select correct sequence the listed stages of bacterial phagocytosis:
1A. approach of the phagocyte to the bacterium
2B. adsorption of bacteria on phagocyte
3B. engulfment of bacteria by phagocyte
4G. phagosome formation
5D. fusion of phagosome with mesosome and formation of phagolysosome
6E. intracellular inactivation of a microbe
7J. enzymatic digestion of bacteria and removal of remaining elements
109. Select the correct sequence of stages of interaction (intercellular cooperation) in the humoral immune response in the case of the introduction of a thymus-independent antigen:
4A. Formation of clones of plasma cells producing antibodies
3B. Antigen recognition by B lymphocytes
2G. Presentation of disintegrated antigen on the macrophage surface
110. An antigen is a substance with the following properties:
Immunogenicity (tolerogenicity), determined by foreignness
Specificity
111. Number of immunoglobulin classes in humans: five
112. IgGin the blood serum of a healthy adult is the total content of immunoglobulins: 75-80%
113. During electrophoresis of human blood serumIgmigrate to the area:γ-globulins
Production of antibodies of different classes
115. The receptor for sheep erythrocytes is present on the membrane: T-lymphocyte
116. B-lymphocytes form rosettes with:
mouse erythrocytes treated with antibodies and complement
117. What factors should be taken into account when assessing immune status:
The frequency of infectious diseases and the nature of their course
Severity of temperature reaction
Presence of foci of chronic infection
Signs of allergization
118. “Zero” lymphocytes and their number in the human body are:
lymphocytes that have not undergone differentiation, which are precursor cells, their number is 10-20%
119. Immunity is:
Biological protection system internal environment multicellular organism(maintaining homeostasis) from genetically foreign substances of exogenous and endogenous nature
120. Antigens are:
Any substances contained in microorganisms and other cells or secreted by them, which carry signs of foreign information and, when introduced into the body, cause the development of specific immune reactions (all known antigens are of colloidal nature) + proteins. polysaccharides, phospholipids. nucleic acids
121. Immunogenicity is:
Ability to induce an immune response
122. Haptens are:
Simple chemical compounds of low molecular weight (disaccharides, lipids, peptides, nucleic acids)
Incomplete antigens
Not immunogenic
Have high level specificity to immune response products
123. The main class of human immunoglobulins that are cytophilic and provide an immediate hypersensitivity reaction is: IgE
124. During the primary immune response, the synthesis of antibodies begins with a class of immunoglobulins:
125. During a secondary immune response, antibody synthesis begins with a class of immunoglobulins:
126. The main cells of the human body that provide the pathochemical phase of the immediate hypersensitivity reaction, releasing histamine and other mediators, are:
Basophils and mast cells
127. Delayed hypersensitivity reactions involve:
T helper cells, T suppressor cells, macrophages and memory cells
128. The maturation and accumulation of which mammalian peripheral blood cells never occurs in the bone marrow:
T lymphocytes
129. Find correspondence between the type of hypersensitivity and the mechanism of implementation:
1.Anaphylactic reaction– production of IgE antibodies upon initial contact with the allergen, antibodies are fixed on the surface of basophils and mast cells, upon repeated exposure to the allergen, mediators are released - histamine, seratonin, etc.
2. Cytotoxic reactions– participate IgG antibodies, IgM, IgA, fixed on various cells, the AG-AT complex activates the complement system along the classical pathway, trace. cell cytolysis.
3.Immunocomplex reactions– formation of IC (soluble antigen associated with antibody + complement), complexes are fixed on immunocompetent cells and deposited in tissues.
4. Cell-mediated reactions– the antigen interacts with pre-sensitized immunocompetent cells, these cells begin to produce mediators, causing inflammation (DTH)
130. Find correspondence between the pathway of complement activation and the mechanism of implementation:
1. Alternative path– due to polysaccharides, lipopolysaccharides of bacteria, viruses (AG without the participation of antibodies), the C3b component binds, with the help of the properdin protein this complex activates the C5 component, then the formation of MAC => lysis of microbial cells
2. Classic way– due to the Ag-At complex (complexes of IgM, IgG with antigens, binding of component C1, cleavage of components C2 and C4, formation of C3 convertase, formation of component C5
3 .Lectin pathway– due to mannan-binding lectin (MBL), activation of protease, cleavage of components C2-C4, classic version. Paths
131. Antigen processing is:
The phenomenon of recognition of a foreign antigen by the capture, cleavage and binding of antigen peptides with molecules of the major histocompatibility complex class 2 and their presentation on the cell surface
? 132. Find correspondence between the properties of the antigen and the development of the immune response:
Specificity -
Immunogenicity -
133. Find correspondence between the type of lymphocytes, their quantity, properties and the way of their differentiation:
1. T-helpers, C D 4-lymphocytes – APC is activated, together with the MHC class 2 molecule, division of the population into Th1 and Th2 (differing in interleukins), form memory cells, and Th1 can turn into cytotoxic cells, differentiation in the thymus, 45-55%
2.C D 8 - lymphocytes - cytotoxic effect, activated by class 1 MHC molecule, can play the role of suppressor cells, form memory cells, destroy target cells (“lethal blow”), 22-24%
3.B lymphocyte - differentiation in the bone marrow, the receptor receives only one receptor, can, after interaction with the antigen, go into the T-dependent pathway (due to IL-2 T-helper, the formation of memory cells and other classes of immunoglobulins) or T-independent (only IgM are formed) .10-15%
134. The main role of cytokines:
Regulator of intercellular interactions (mediator)
135. Cells involved in presenting antigen to T lymphocytes are:
Dendritic cells
Macrophages
Langerhans cells
B lymphocytes
136. To produce antibodies, B lymphocytes receive help from:
T helper cells
137. T lymphocytes recognize antigens that are presented in association with molecules:
Major histocompatibility complex on the surface of antigen presenting cells)
138. Antibodies classIgEare being developed: at allergic reactions, plasma cells in the bronchial and peritoneal lymph nodes, in the mucous membrane of the gastrointestinal tract
139. The phagocytic reaction is performed:
neutrophils
eosinophils
basophils
macrophages
monocytes
140. Neutrophil leukocytes have the following functions:
Capable of phagocytosis
Secrete a wide range of biologically active substances (IL-8 causes degranulation)
Associated with the regulation of tissue metabolism and the cascade of inflammatory reactions
141. The following occurs in the thymus: maturation and differentiation of T lymphocytes
142. The major histocompatibility complex (MHC) is responsible for:
A. are markers of the individuality of their body
B. are formed when the cells of the body are damaged by any agents (infectious) and mark cells that must be destroyed by T-killers
V. participate in immunoregulation, represent antigenic determinants on the membrane of macrophages and interact with T helper cells
143. Antibody formation occurs in: plasma cells
144. Antibodies classIgGcan:
Pass through the placenta
Opsonization of corpuscular antigens
Complement binding and activation via the classical pathway
Bacteriolysis and neutralization of toxigens
Agglutination and precipitation of antigens
145. Primary immunodeficiencies develop as a result of:
Defects in genes (such as mutations) that control the immune system
146. Cytokines include:
interleukins (1,2,3,4, etc.)
colony-stimulating factors
interferons
tumor necrosis factors
macrophage inhibitory factor
147. Find correspondence between various cytokines and their main properties:
1.Hematopoietins- cell growth factors (ID provides growth stimulation, differentiation and activation of T-.B-lymphocytes,N.K.-cells, etc.) and colony-stimulating factors
2.Interferons– antiviral activity
3.Tumor necrosis factors– lyses some tumors, stimulates antibody formation and mononuclear cell activity
4.Chemokines -attract leukocytes, monocytes, lymphocytes to the site of inflammation
148. Cells that synthesize cytokines are:
activated T lymphocytes
macrophages
thymic stromal cells
monocytes
mast cells
149. Allergens are:
1.full antigens of protein nature:
food products (eggs, milk, nuts, shellfish); poisons of bees, wasps; hormones; animal serum; enzyme preparations(streptokinase, etc.); latex; Components house dust(mites, mushrooms, etc.); pollen of grasses and trees; vaccine components
150. Find correspondence between the level of tests characterizing immune status human, and the main indicators of the immune system:
1st level- screening ( leukocyte formula, determination of phagocytosis activity by the intensity of chemotaxis, determination of immunoglobulin classes, counting the number of B-lymphocytes in the blood, determination of the total number of lymphocytes and the percentage of mature T-lymphocytes)
2nd level – quantities. determination of T-helpers/inducers and T-killers/suppressors, determination of the expression of adhesion molecules on the surface membrane of neutrophils, assessment of the proliferative activity of lymphocytes for the main mitogens, determination of proteins of the complement system, determination of proteins acute phase, subclasses of immunoglobulins, determination of the presence of autoantibodies, performing skin tests
151. Find correspondence between the form of the infectious process and its characteristics:
By origin : exogenous– the pathogenic agent comes from outside
endogenous– the cause of the development of infection is a representative of the opportunistic microflora of the macroorganism itself
autoinfection– when pathogens are introduced from one biotope of a macroorganism to another
By duration : acute, subacute and chronic (the pathogen persists for a long time)
By distribution : focal (localized) and generalized (spread through the lymphatic tract or hematogenously): bacteremia, sepsis and septicopyemia
According to the site of infection : community-acquired, hospital-acquired, natural-focal
152. Select the correct sequence of periods in the development of an infectious disease:
1.incubation period
2.prodormal period
3.period expressed clinical symptoms(acute period)
4. period of convalescence (recovery) - possible bacterial carriage
153. Find correspondences between the type of bacterial toxin and their properties:
1.cytotoxins– block protein synthesis at the subcellular level
2. membrane toxins– increase surface permeability. membranes of erythrocytes and leukocytes
3.functional blockers- perversion of transmission nerve impulse, increased vascular permeability
4.exfoliatins and erythrogenins
154. Allergens contain:
155. Incubation period This: the time from the moment a microbe enters the body until the first signs of disease appear, which is associated with reproduction, accumulation of microbes and toxin
dependent and oxygen-independent mechanisms of bactericidal activity. Opsonins. Methods
studying the phagocytic activity of cells.
Phagocytosis is a process in which blood cells specially designed for this purpose and
body tissues (phagocytes) capture and digest solid particles.
Carried out by two types of cells: granular cells circulating in the blood
leukocytes (granulocytes) and tissue macrophages.
Stages of phagocytosis:
1. Chemotaxis. In the phagocytosis reaction, a more important role belongs to the positive
chemotaxis. Products secreted act as chemoattractants
microorganisms and activated cells at the site of inflammation (cytokines, leukotriene
B4, histamine), as well as breakdown products of complement components (C3a, C5a),
proteolytic fragments of blood coagulation and fibrinolysis factors (thrombin,
fibrin), neuropeptides, fragments of immunoglobulins, etc. However, “professional”
Chemotaxins are cytokines from the chemokine group. Before other cells reach the site of inflammation
Neutrophils migrate, macrophages arrive much later. Speed
chemotactic movement for neutrophils and macrophages is comparable, differences in
arrival times are probably associated with different rates of activation.
2. Adhesion phagocytes to the object. Caused by the presence of phagocytes on the surface
receptors for molecules present on the surface of an object (its own or
contacted him). During phagocytosis of bacteria or old cells of the host body
recognition of terminal saccharide groups occurs - glucose, galactose, fucose,
mannose, etc., which are presented on the surface of phagocytosed cells.
Recognition is carried out by lectin-like receptors of the corresponding
specificity, primarily mannose binding protein and selectins,
present on the surface of phagocytes. In cases where the objects of phagocytosis
are not living cells, but pieces of coal, asbestos, glass, metal, etc., phagocytes
first make the absorption object acceptable for the reaction,
enveloping it with its own products, including components of the intercellular
matrix they produce. Although phagocytes are capable of absorbing various types of
“unprepared” objects, the phagocytic process reaches its greatest intensity
during opsonization, i.e. fixation on the surface of objects of opsonins to which phagocytes
there are specific receptors - for the Fc fragment of antibodies, components of the system
complement, fibronectin, etc.
3. Activation membranes. At this stage, the object is prepared for immersion.
Protein kinase C is activated and calcium ions are released from intracellular stores.
Sol-gel transitions in the system of cellular colloids and actino-
myosin rearrangements.
4. Dive. The object is enveloped.
5. Phagosome formation. Closing the membrane, immersing an object with part of the membrane
phagocyte inside the cell.
6. Phagolysosome formation. Fusion of the phagosome with lysosomes, resulting in
optimal conditions are formed for bacteriolysis and breakdown of the killed cell.
The mechanisms of bringing the phagosome and lysosomes closer together are unclear; there is probably an active
movement of lysosomes to phagosomes.
7. Killing and splitting. The role of the cell wall of the cell being digested is great. Basic
substances involved in bacteriolysis: hydrogen peroxide, products of nitrogen metabolism,
lysozyme, etc. The process of destruction of bacterial cells is completed due to the activity
proteases, nucleases, lipases and other enzymes whose activity is optimal at low
pH values.
8. Release of degradation products.
Phagocytosis can be:
Completed (killing and digestion were successful);
Incomplete (for a number of pathogens, phagocytosis is a necessary step in their life cycle, for example, in mycobacteria and gonococci).
Oxygen-dependent microbicidal activity is realized through the formation of a significant amount of products with toxic effects that damage microorganisms and surrounding structures. NLDP oxidase (flavoprotedo-cytochrome reductase) of the plasma membrane and cytochrome b are responsible for their formation; in the presence of quinones, this complex transforms 02 into the superoxide anion (02-). The latter exhibits a pronounced damaging effect, and is also quickly transformed into hydrogen peroxide according to the scheme: 202 + H20 = H202 + O2 (process
catalyzes the enzyme superoxide dismutase).
Opsonins are proteins that enhance phagocytosis: IgG, acute phase proteins (C-reactive protein,
mannan-binding lectin); lipopolysaccharide-binding protein, complement components - C3b, C4b; surfactant proteins of the lungs SP-A, SP-D.
Methods for studying the phagocytic activity of cells.
To assess the phagocytic activity of peripheral blood leukocytes, 0.25 ml of a microbial culture suspension with a concentration of 2 billion microbes in 1 ml is added to citrated blood taken from a finger in a volume of 0.2 ml.
The mixture is incubated for 30 minutes at 37°C, centrifuged at 1500 rpm for 5-6 minutes, and the supernatant is removed. A thin silvery layer of leukocytes is carefully sucked out, smears are prepared, dried, fixed, and painted with Romanovsky-Giemsa paint. The preparations are dried and microscopically examined.
The count of absorbed microbes is carried out in 200 neutrophils (50 monocytes). The intensity of the reaction is assessed using the following indicators:
1. Phagocytic indicator (phagocytic activity) - the percentage of phagocytes from the number of counted cells.
2. Phagocytic number (phagocytic index) - the average number of microbes absorbed by one active phagocyte.
To determine the digestive ability of peripheral blood leukocytes, prepare a mixture of the taken blood and a suspension of the microorganism and keep it in a thermostat at 37°C for 2 hours. Preparation of smears is similar. During microscopy of the preparation, viable microbial cells are increased in size, while digested ones are less intensely colored and smaller in size. To assess the digestive function, the indicator of completeness of phagocytosis is used - the ratio of the number of digested microbes to total number absorbed microbes, expressed as a percentage.