Lecture 1 Flashcards
What organisms are commonly detected using acid-fast stain?
Mycobacteria spp
Why would you use a silver stain?
Organism is too thin to see with microscope - thicken it
What is the most common application of the Giemsa stain?
Peripheral blood smears and blood-bourne parasites.
Where do the cells of a primary cell culture come from?
Directly from animal tissue
How does a toxin-antitoxin test work?
Two animals are inoculated with sample from the clinical case animal. One of the two is also given a specific antibody to the suspected toxin. If the animal given the antibody does not show signs but the animal given only the sample does, then you have successfully identified the toxin.
List five methods for the detection of microbial proteins in a sample.
- Toxin-antitoxin test
- Labelled antibody test/immunofluorescence
- ELISA
- Latex agglutination
- Haemagglutination
What sort of PCR do you use to both identify the pathogen and determine the amount in the original sample?
Real time PCR
What is the high resolution melt curve?
The temperature point at which a DNA strand denatures - species specific, used to narrow down pathogen ID
What are two common fluorescent markers used to ‘label’ antibodies?
Horseradish peroxidase, fluorescin
What is one advantage and one disadvantage of high throughput nucleic acid sequencing?
Advantage: might detect a pathogen you werent expecting
Disadvantage: not readily available technology
How many times should you do serology before you can be sure a certain pathogen has caused the current disease?
At least twice - once during active infection, and again 2 weeks later (antibody titres should be higher in later sample).
Name three tests you might do to detect antibody in a sample (serology).
Latex agglutination, ELISA, neutralisation
Name three ways to quantify the cell-mediated response of an animal.
- Inoculation of a protein from the pathogen into the dermis
- Culture of lymphocytes with the protein and fluorescently- labelled thymidine
- The former plus an ELISA to detect IL-2 and/or IFN-gamma production by lymphocytes
