Antigen -Antibody Interactions Precipitin Reactions

1
Antigen -Antibody InteractionsPrecipitin
Reactions

• Hugh B. Fackrell

2
Antigen-Antibody Interactions

• Assigned Reading
• Content Outline
• Performance Ojectives
• Key terms
• Key Concepts
• Short Answer Questions

3
Assigned Reading

• Chapter 6 pp 144-164
• Janis Kubys Immunology 3rd Ed

4
Content Outline

• Strength of Antigen-Antibody Interactions
• Cross Reactivity
• Precipitin Reactions
• Agglutination Reactions

5
Strength of Antigen-Antibody Interactions

• affinity
• avidity

6
Cross reactivity
7
Mammoth
8
Precipitin Reactions

• reactions in fluids
• reaction in gels
• radial immunodiffusion
• Ouchterlony
• immunoelectrophoresis

9
Ring Test
10
Ring Test Controls
11
C reactive Protein ring test
12
QPT
13
QPT Zones
14
QPT Epitopes
15
(No Transcript)
16
QPT Simple system
17
QPT Multiple Interactions
18
QPT Multiple Reactions
19
Radial Immuno Diffusion
20
Double Immuno Diffusion
21
ImmunodiffusionSingle reactions
22
(No Transcript)
23
(No Transcript)
24
Immunoelectrophoresis
25
Counter Immuno Electrophoresis

• Fig 12-7 Barrett 1988

26
IEF Concept
27
IEF IgG IgM IgA
28
IEF Partial Identity
29
IEF Human Serum
30
Rocket Immunoelectrophoresis
31
Rocket Immunoelectrophoresis 2
32
Rocket Immunoelectrophoresis 3
33
Agglutination Reactions

• hemagglutination
• bacterial agglutination
• passive agglutination
• agglutination inhibition

34
(No Transcript)
35
Hemagglutination
36
The End
37
Performance Objectives

• Key terms, concepts
• short answers

38
Key Terms

• agglutination, direct agglutination reaction,
  indirect agglutination reaction
• antibody affinity, antiserum, association
  constant (K), average affinity,
• average intrinsic association constant(Ka),
  avidity, ELISA, equilibrium constant,
• equilibrium dialysis, fluorescein, fluorochromes,
  hemagglutination,

39

• passive hemagglutination, passive
  hemagglutination inhibition,
• reverse passive hemagglutination, immune
  precipitation, immunoelectrophoresis
• immunofluorescence, Indirect fluorecent antibody
  test, ring test,

40

• Ouchterlony methods, plasma, primary
  antigen-antibody interactions, Radioimmunoassay(RI
  A
• Rhodamine, secondary antigen-antibody
  interactions, serology,
• serum, titer, zone phenomena (antibody excess,
  antigen excess, equivalence)

41
Key Concepts

• Explain a primary antigen-antibody interaction
  and include at least three important
  characteristics.
• Describe the forces that encourage primary
  antigen-Antibody interactions
• Assess the reasons for using the different gel
  preciptitin reactions

42

• Distinguish betweeen antibody affinity and
  avidity.
• Describe the strength of the primary
  antigen-antibody interactions using equilibrium
  dialysis. Include the terms K and Ka
• Compare and contrast RIA and ELISA
• Describe direct and indirect fluorescent antibody
  methods.
• Explain zone phenomena.

43

• Describe a secondary antigen-antibody interaction
  in terms of lattice formation and
  antigenantibody ratios.
• Construct a table to compare the various
  procedures used to determine the presence of
  soluble antigen or antibody in a fluid and in a
  gel.
• Distinguish between agglutination and preciptin
  reactions and give the advantages and
  disadvantages of each.

44
Short Answer Questions
45

• Cross reactivity of antibodies creates problems
  for their application in serology. Explain.
• Differentiate between a primary and a secondary
  antigen-antibody reaction.
• What are three important characteristics that
  distinguish the two reactions?

46

• What kinds of noncovalent interactions are
  important in antigen-antibody interactions? What
  aspect of these interactions is most important
  and why?
• How is equilibrium dialysis used to measure
  PRIMARY antigen-antibody reactions?
• Differentiate between avidity and affinity.

47

• Discuss the term lattice formation.
• What are the pros and cons of RIA?
• Describe two types of immunofluorescence tests.
• What is the advantages of the indirect procedure
  over the direct procedure?
• What are some commonly used fluors?
• What colour does each fluor emit?
• What makes precipitin reactions visible?

48

• What two factors are important in the development
  of precipitin reactions?
• Three patterns can be observed in the Ouchterlony
  test. DRAW and LABEL diagrams to illustrate these
  patterns. What does each pattern show?
• What is the major advantage of immunoelectrophores
  is over immunodiffusion?
• What are the disadvantages?

49

• How does agglutination differ from precipitation?
• Why are agglutinatin tests more sensitive that
  precipitin tests?
• Differentiate between direct and indirect
  agglutination reactions?
• What is a major advantage of indirect
  agglutination reaction over direct reactions?

50
Ouchterlony
51
OuchterlonyPartial Identity