Immunology Testing Flashcards
What is serology?
The science of detection and measurement of antibodies or antigens
What is specificity
The ability of a test to produce no false positives
If a specificity test is positive what can you be certain of?
They actually have the disease
What is a sensitivity test
A test able to produce no false negatives
If a sensitivity test is negative what can you be certain of?
They don’t have the disease
What does a sensitivity test help do
Rule out the disease
What are monoclonal antibodies?
Antibody specific to Ag
Immunization of an animal with an antigen to stimulate the production of antibody. What is the antibody produced?
Monoclonal antibodies
True or false corn the resulting reaction of antigen with this monoclonal antibody is diagnostically significant/very specific
True
What are examples of serologic test?
ELISA
CELISA
LATEX AGGLUTINATION
RIM(rapid immunomigtation
What does ELISA stand for
Enzyme linked immunosobent assay
What does the ELISA test for?
Specific antigen or antibody
Does FIV snap test test for antibodies or both antigen and antibodies
Antibody
Does triple snap test test for antibodies or both antigen and antibodies
Antigens and antibodies
What can the ELISA detect
Viruses, bacteria, parasites, hormones
True or false specificity of ELISE is high
True
What happens during an ELISA test?
Anybody is bound to the membrane or walls of wells in the test, antigen if present is in the sample being tested, antigen binds to antibody into second enzyme linked in a body, rinse stage, happens within the test
What is chromogenic substrate?
Color producing
Does the ELISA test have chromogenic substrate
Yes
What does the chromogenic substrate react with to develop a specific color?
Enzyme
What does the color indicate in ELISA test
Presence of antigen
What does CELISA stand for
Competitive enzyme linked in immuno sorbent assay
What test does enzyme labeled antigen and antigen from the sample complete for antibody on the test membrane or walls of the well?
CELISA
What happens during a CELISA test
Color developer reacts with enzyme, intensity of color, corresponds to the concentration of patient antigen
What are examples of the CELISA test
Feline pancreatitis, equine infectious anemia
What is the RIM test?
Immunochromatography or lateral flow immunoassay
What happens during REM test?
Colloidal gold is attached to antibodies specific for the antigen, these are present in the membrane of the test where the patient sample is applied, the AG – AB complex is migrating along the membrane to another area of the test where it is read, a second antibody(containing gold) is present in the membrane of the second area, the second body captures the AG – AB complex with the gold, causing a color change equals positive
What are examples of serologic test sent out to reference labs?
Immunodiffusion, coombs test, complement fixation, immunofluorescence, immunoelectron microscopy, virus neutralization, polymerase chain reaction(PCR)
What is immunodiffusion?
Antigen from the test kit and antibody from the sample are placed in separate wells in an agar gel plate, components diffuse into the Egar and when they meet, they form a G – AB complex, this looks like a visible band in the gel
If no band form during immunodiffusion, what does this mean?
No antibodies exist in the patient sample
What is the coombs test?
Detect auto antibodies, used to detect anybody that has attacked the body’s own red blood cells
What does a positive result for coombs test mean?
Immune meeting, mediated hemolytic disease
How do you perform form a coombs test?
Come on patient sample with antisera. If agglutination is visible, then the test is positive.
What is an indirect coombs test?
Patient serum mixed with normal red blood cells from same species
What indicates a positive indirect coombs test
If antibody is present in the patient serum agglutination will be present
What is fluorescent antibody testing often used for?
To verify an in-house test
What are the two types of fluorescent antibody testing and what do they detect?
Direct an indirect antibody testing – both detect presence of specific antibody and sample
What is the technique for direct fluorescent antibody testing?
Test slide coded with fluorescent dyed agent, antigen if present is in the sample, slide is examine for presence of fluorescence
What is the technique for indirect fluorescence antibody testing?
Side contains the specific test antigen, sample is incubated with slide, slide is washed to remove any unbound, fluorescent labeled antibody is added, examine for fluorescence
True or false: any fluorescent is a positive test for fluorescent body test testing
True
What are interdermal test used for?
Diagnose allergies
Allergies are mediated by what antibodies
IgE
How do you perform an interdermal test?
Extracts of allergens are injected intradermally, injection sites are monitored for allergic reaction reactions
What indicates a positive intradermal test
Raised welt
What is antibody titers
Distinguish between an active infection and a prior exposure to certain allergens
True or false: titer refers to the greatest dilution at which a patient sample no longer yields a positive result for presence of specific antibody
True
True or false antibody titer requires making cereal dilutions of a sample
True
What does high tighter indicate?
Active infection
What does low tighter indicate?
Previous exposure
True or false: antibody concentration is not necessarily synonymous with immunity
True
What titers are currently available?
Canine distemper, canine parvovirus, feline panleukopenia
What two laboratories offer rabies titer testing
Kansas State University, rabies laboratory USDA’s animal disease, diagnostic laboratory in Ames, Iowa
What does molecular diagnostic test analyze?
DNA or RNA, identifies a specific pathogen
What are the advantages to molecular diagnostic testing?
Increase sensitivity, increase specificity, small amount of sample, test are safe, faster turnaround time
What are disadvantages to molecular diagnostic test?
Contamination will lead to false positives, technical expertise needed, high cost, large space required
What does PCR stand for?
Polymerase chain reaction
What does PCR test detect?
Small specific segment of DNA
True or false the sequencing of the DNAsegment must be known prior to testing for
True
True or false copies of the DNA segment are made through denaturation, annealing, and extension
True
True or false gel electrophoresis is used to determine if the segment is present for a PCR test testing
True
True or false FIP cannot be confirmed with PCR test testing
False
True or false fecal PCR test for canine schistosomiasis
True
