introduction to lab ex. 22: immunology i - bacterial agglutination - immunoprecipitation
TRANSCRIPT
Introduction to Lab Ex. 22: Immunology I
- Bacterial Agglutination
- Immunoprecipitation
Introduction to Lab Ex. 22: Immunology I – Bacterial Agglutination- Immunoprecipitation
Immune responses include all the activities of the immune systemtoward maintaining the healthy status of the host.
These would include protecting against pathogens – foreign antigens
Specific Immune responses are one of two kinds: Antibody-mediated Cell-mediated
Antibodies are proteins secreted by specific immune cells to counteract and rid the antigens (and thus the pathogens they may be associated with)
Antibodies are specific for the antigen that trigger their formation.Depending on the nature of the antigen the antigen-antibody reactions
result in different reactions, ex. Agglutination or precipitation
Table 1. Serological classification of some common Salmonella species.
Salmonella species Serological groupS. typhimurium B S. paratyphi C C1 S. enteriditis D S. anatum E
agglutination no agglutination?
Antibody specificity known (S. enteriditis)Salmonella species identity not known (?)Agglutinationreaction between antibody and particulate antigen
BACTERIAL AGGLUTINATION. is the reaction between a particulate antigen and its specific antibodies
Bacterial agglutination
?
Bacterial agglutination
?
agglutination no agglutination
S. aureus S. epidermidis
agglutination no agglutination?
Antibody specificity known (S. aureus)- antigen on the surface of bacteria Staphylococcus species identity not known (?)
Bacterial agglutination
Bacterial agglutination
S. aureus S. epidermidis
?
agglutination no agglutination
S. aureus S. epidermidis
Latex beads(dyed blue)
S. aureus-specificantibodies
Bacterial agglutination
S. aureus S. epidermidis
?
agglutination no agglutination
Note: these latex beads are dyed red
S. aureus S. epidermidis
Bacterial agglutination (new procedure).
#1Mark your bacterial agglutination cards
S. aureus S. epidermidis
Bacterial agglutination
#2Mix the latex agglutination reagent dropper bottle and dispense one drop onto each circle
Bacterial agglutination
#3Using a sterile toothpick , pick up and smear 1 suspect colony from your negative control in the proper ring.
#4Using a NEW sterile toothpick , pick up and smear 1 suspect colony from your positive control in the proper ring.
#5Using a NEW sterile toothpick , pick up and smear 1 suspect colony from your unknown in the proper ring.
S. aureus S. epidermidis
S. aureus S. epidermidis
Bacterial agglutination (Part B).
#6Pick up and gently rock the card for 20 seconds and observe for agglutination under normal lighting conditions
?Bacterial antigen: Agglutination with anti-S. aureus :
S. aureus
S. epidermidis
unknown
Immunoprecipitation- is the reaction between a soluble antigen and its specific antibodies-soluble antigens are smaller and in solution; complexing with antibodies make these
bigger and they fall out of solution as a precipitate –visible to the eye.
Antibody specificity known (toxin, protein, etc.)Antigen presence or identity not known (?)Precipitationreaction between antibody and soluble antigen
Immunoprecipitation
Antibody specificity known (toxin, protein, etc.)Antigen presence or identity not known (?)Precipitationreaction between antibody and soluble antigen
Immunoprecipitation
Immunoprecipitation
Reaction of nonidentity
Reaction ofidentity