Test 5 Flashcards
In latex agglutination the latex particle is
carrier of antibody or antigen
What is the ratio of blood: H2O: 2.7% NaCl used for lysis of erythrocytes in procedure of separation of all leukocytes from whole blood?
1:2:1
For evaluation of differential white cell count, the blood smear is stained by
Pappenheim
Which immune cells are professional phagocytes?
neutrophils, monocytes and macrophages
Granules in eosiniphils stained by Pappenheim are
Red
In test for respiratory burst activity in phagocytes tetrazolium salt is
reduced into a coloured formazan
Immune responses of organisms can be detected in two ways - they are?
1) detection of antigen by the help of specific antibody
2) detection of the presence of specific antibodies in the serum - determination whether an animal has been previously exposed to a specific antigen
Define antigens and antibodies:
Antigens are molecules that stimulate immune response
Antibodies are antigen-binding proteins secreted by plasma cells or present in the B-cell membrane
Injection of Ag into body –> production of Ab –> form a complex and Ag is destroyed by help of other immune mechanisms
The three tests that are most applied in agglutination include:
Slide agglutination - direct and indirect or passive (latex agglutination)
Tube agglutination
Haemagglutination
Positive result in slide agglutination is identified by
Visible clumping with clearing of the suspension
Tube agglutination is a direct agglutination and can be readily used to
Determine titer of antibodies
Negative agglutination
Solid ‘‘button’’ sediment with turbid supernatant
Name two types of haemagglutination tests
Direct haemagglutination - detect antibodies against red cell determinants
Passive haemagglutination - against compounds artificially coupled to red cells
The essential differences between agglutination and precipitation are in:
Size, solubility and location of antigen
In agglutination antigens are whole cells, in precipitation antigens are a soluble molecule
Radial immunodiffusion (RID) is
a quantitative method used for quantification
Immunoelectrophoresis (IEF) is
a precipitation reaction, in which direct current is used to regulate the movement of antigen and antibody molecules in agar or agarosis gel
Separation of proteins in electric field depends on:
Whole electric charge
Molecular mass
Isoelectric point
Serum proteins separate into six major fractions according to their charge at a given pH:
- alpha1 - globulins
- alpha2-globulins
- beta-globulins
- gamma-globulins
- hydragel protein K20
- hydragel proteins E
Result of ELISA reaction
soluble colour product
Application of EIA can be used for:
Qualitative detection of presence of Ag or Ab
Quantitative determination of Ag or Ab
Advantages and disadvantage of EIA
Direct detection of Ag of pathogens
Detection of Ab against many bacterial, viral or parasitic agents
Very flexible method
Disadvantage: can give false positive results
ELISA techniques are divided to what groups?
Detection of antigens: sandwich ELISA and competitive ELISA
Detection of antibodies: direct ELISA and blocking ELISA
Separation of leukocytes. Immunologically non-specific and specific:
Immunologically non-specific: size, density, electric charge and adherence abilities
Immunologically specific: CD markers
Granulocytes with Pappenheim
Purple or red
