- •Medical faculty
- •Infection. Innate immunity. Nonspecific factors of host defence
- •3. Period of specific clinical signs and symptoms.
- •Types of infectious diseases
- •Susceptible macroorganism (host)
- •Potentially harmful infectious agent (microbe)
- •Environmental conditions.
- •Environmental conditions
- •Mechanisms of Transmission
- •Portals of Entry and Exit
- •Table 11-1
- •Microorganism
- •Virulence Factors
- •Macroorganism (Nonspesific factors of host defense)
- •Mechanical defenses
- •Chemical defenses
- •Immunobiological defenses (humoral and cellular factors)
- •Practical work
- •Determination of k.Pneumoniae virulence
- •2. Determination of bacterial virulence factors:
- •Hemolysins (hemolytic activity)
- •Coagulase activity
- •Lecithinase activity
- •Capsules
- •3. Phagocytosis (complete phagocytosis and incomplete phagocytosis).
- •Practical tasks
- •Antigens
- •Antibodies
- •The Agglutination Tests
- •The Precipitation Tests
- •Diagnosticums. Antibody-containing antisera
- •Practical work
- •Practical tasks
- •The Complement
- •Lysis Tests
- •The Complement Fixation Test
- •The Complement Titration
- •The Neutralization Reactions
- •Practical work
- •Practical tasks
- •Serological Reactions with Labeled Components
- •Immunofluorescence (if-test)
- •Enzyme-Linked Immunosorbent Assay (elisa)
- •Radioimmunoassay (ria)
- •Immunoblotting (Western Analysis)
- •Practical work
- •Practical tasks
- •Table 15-1
- •Active immunity
- •Passive immunity
- •Complications of Passive Immunotherapy
- •Practical work
- •The Vaccine Control
- •The Scheme of Vaccine Control
- •The Diphtheria Toxoid Control
- •3. Determination of Diphtheria Toxoid Titer
- •Practical tasks
- •The Scheme of Flocculation Test
- •Topics for Discussion.
- •Infection and immunity.
- •Types of Vaccines
- •Preparations for Passive Immunization
- •Immunologic reactions for diagnosis of infectious diseases.
- •Immune biological preparations for treatment and immunoprophylaxis.
- •Written test for Review on section: «infection and immunity».
Practical tasks
1. Examine the results of serial dilution agglutination test to detect the unknown antibodies against O- and H-antigens (the demonstration). Draw and fill in Table 12-1 in your protocol notebook. Make a conclusion.
Perform the slide agglutination test with non-absorbed and pre-absorbed antisera to identify the unknown antigen in the pure culture isolated from the patient’s specimen. Estimate the results. Draw the picture what you have observed. Make a conclusion.
Interpret the results of the indirect hemagglutination test (the demonstration). Write down Table 12-2 and register the results in the protocol notebook.
Identify the unknown protein by using the precipitin ring test. Enter the results in Table 12-3. Make a conclusion.
Perform the precipitin ring test to identify the unknown hapten in the sample. Denote the positive test with (+) and negative results with (-) in Table 12-4.. Draw the picture of the tubes in the album. Make a conclusion.
Table 12-4
The Scheme of the Precipitin Ring Test to Identify the Unknown Hapten
Ingredients |
Unknown hapten |
Precipitating antiserum against B .cereus |
|
Precipitating antiserum against E. coli |
|
Conclusion: the unknown hapten belongs to ___________________________________.
|
|
LESSON 13
SEROLOGICAL DIAGNOSTIC REACTIONS (LYSIS TESTS, the COMPLEMENT-FIXATION TEST)
Prelab conference. Topics for discussion:
Lysis tests (bacteriolysis, immune hemolysis). Mechanism, components, application.
The complement system. The pathways of complement.
The titration of complement.
Hemolytic system. Composition and application.
Complement-fixation test (CF-test). Mechanism, components and application.
The Complement
At the beginning of 20th century it was recognized that a heat-labile component of normal serum was necessary for immune lysis of red blood cells. The term complement was given to this component since it functioned to «complement» the action of specific antibody in the destruction of bacteria and erythrocytes. Complement is a sequential, multimolecular system of plasma proteins which can be activated by a variety of immunological as well as nonimmunological stimuli. Complement activation, which can proceed via two different pathways, is mediated through a series of cascading reaction steps. The classical complement pathway is activated by Ig G- and IgM-containing immune complexes and is composed of eleven distinct plasma proteins which identified numerically as C1-C9. The alternative complement pathway is activated by plant, fungal, and bacterial polysaccharides and lipopolysaccharides in particulate form and is composed of six plasma proteins identified as factor D, factor B, properdin, factor H, factor 1, and C3. In addition, C5-C9 can be recruited to attack membrane surfaces as in the classical pathway. The C3 -C9 components are thus common to both pathways.
Activation of either pathway results in a variety of biological effects. These include: (1)the irreversible damage to biological membranes associated with complement dependent cytolysis, (2)the deposition of molecules on the surface of the particle under complement attack resulting in particle opsonization and clearance, and (3)the production of potent mediators of the inflammatory response.