Chapter 6 Antigen-Antibody Interactions Dr. Capers Slide 2 Kuby
IMMUNOLOGY Sixth Edition Chapter 6 Antigen-Antibody Interactions:
Principles and Applications Copyright 2007 by W. H. Freeman and
Company Kindt Goldsby Osborne Slide 3 Antigen-Antibody (Ag-Ab)
Interaction Similar to enzyme-substrate interaction However, does
not lead to irreversible chemical alteration in either the antibody
or antigen Slide 4 Noncovalent Interactions Hydrogen bonds Ionic
bonds Hydrophobic reactions Van der Waals All weak so need
combination of all of them to make strong interaction Slide 5
Cross-reactivity Mechanisms of tolerance prevent formation of Abs
against ones own blood group antigens However, exposure to
microbial antigens on intestinal bacteria induce formation of Abs,
these antigens share similarity to blood group antigens Slide 6
Immunoassays measuring Ag-Ab interactions Vital roles: Diagnosing
disease Monitoring level of humoral response Identifying molecules
of biological or medical interest Slide 7 Precipitation Reactions
Ag-Ab interactions can form visible precipitate Examples: Radial
immunodiffusion Double immunodiffusion immunoelectrophoresis Slide
8 In this example, Anti-dog IgG is Mixed in agar so only what is
Placed in wells (Ag) diffuses out Slide 9 In this example, both
antibody and antigen diffuse Out of wells Slide 10
Immunoelectrophoresis Antigen is 1 st put into wells, charge is
applied to separate components of antigen mixture, then troughs are
cut and antibody is allowed to diffuse through gel Slide 11
Agglutination Reactions Visible clumping agglutination Examples:
Hemagglutination Bacterial Agglutination Important in all tests for
Antibody to be in right concentation Too much antibody will cause
univalent binding, need multivalent for preciptitate or
agglutination to occur Slide 12 ELISA Enzyme-Linked Immunosorbent
Assay Examples: Indirect ELISA Sandwich ELISA Competitive ELISA
Slide 13 Indirect ELISA Used to determine if a particular antibody
is present Slide 14 Slide 15 Slide 16 Slide 17 Immunoprecipitation
Using microscopic magnetic beads Below is cell with magnetic beads
attached Slide 18 Slide 19 Immunofluorescence Slide 20 Using
Immunofluorescence to see the effect of cancer treatments E.
decrease beta-tubulin III (found in developing neurons, if found in
other tissue it can be used as cancer marker) F. decrease
thymidilate kinase (needed by tumor cell to repair DNA) Slide 21
Flow Cytometry Can provide quantitative data
