Immunological and Molecular Diagnostics

Question 1

How can serology be used to evaluate immune function? (3)

Answer 1

Can measure exposure of animal to pathogen, response to vaccine or can diagnose immune-mediated deficiency (allergy, autoimmune, immunodeficiency)

Question 2

What can a immunoassay using antibodies as a detection reagent be used for? (3)

Answer 2

Presence of specific pathogen, measurement of biomarker, immunophenotyping

Question 3

What are the serological markers used for innate and adaptive immunity?

Answer 3

Innate - acute phase proteins; used to provide evidence of inflam diseases in horses.
Adaptive - antibodies, cytokines.

Question 4

When type of immunoglobulins measurements can be done when sampling the adaptive immune system through serology? (2)

Answer 4

Total immunoglobulins or antigen-specific immunoglobulins.

Question 5

What are some uses of measuring total immunoglobulin?

Answer 5

Failure of passive transfer in foals, Specific IgG deficiencies, Mono/polyclonal gammopathies

Question 6

What are some uses of measuring antigen-specific immunoglobulins?

Answer 6

Exposure to specific pathogen, response to vaccine, diagnosis of antibody-mediated hypersensitivity

Question 7

How can CD4+ T-cell responses be evaluated? Give some examples of when this is used.

Answer 7

T-cell response can be measured by cytokine release following stimulation with antigen. E.g. bovine IFN-gamma ELISA for bovine TV, or intradermal skin test for bovine TB.

Question 8

If you wanted to detect a pathogen using antibodies, what type of assay would you use for A) biological fluids/faeces B) smears/tissue section C) tissue section

Answer 8

A) Sandwich ELISA
B) ImmunoFluorescence
C) Immunohistochemistry

Question 9

What is Immunophenotyping?

Answer 9

It uses antibodies against cell-surface markers to determine which type of cells are in a sample.

Question 10

How can molecular diagnostics be used to identify pathogens?

Answer 10

Samples can be tested for RNA/DNA from specific pathogens.This involved performing PCR/Quantitative PCR, using specific primers/probes.

Question 11

How can DNA genotyping be used?

Answer 11

Establish parentage, diagnosis disease (e.g. KIT mutation for CMCT), screen for carrier animals, determine potential risk in later life.