Immunology Lab Final Material Flashcards
3 Ways to Look at Failure of Passive Transfer in foals
- Refractometry
- ELISA
- Radial Immunodiffusion (RID)
factors to decide what test
sensitivity, specificity, time frame for results, ease of use, cost
Refractometry
measure of refractive index of a sample
what are we measuring directly with a refractometer?
refractive index
what are we measuring indirectly with a refractometer?
total protein content of serum
refractive index
relative velocity of light of light in a medium compared to through the air (higher the number, the slower it moves)
SNAP Foal IgG test
ELISA, AB specific for equine IgG already bound to test, whole blood added on sample spot, then conjugate (peroxidase labeled anti-equine IgG)
how to read a snap foal test
color relative to <400 and >800 mg/dl ranges
which test gives the most precise levels?
radioimmunodiffusion (RID)
Radioimmunodiffusion
specific test that precipitates an Ag-Ab complex in the gel (agar has anti-canine IgG), add serum, measure ring, plot the squared value on regression graph compared to controls
canine immunoproliferative disorders
abnormal proliferation of Ig-producing cells and an excess of Ig
3 types of canine immunoproliferative disorders
- multiple myeloma (a monoclonal gammopathy, proliferation of plasma cells)
- macroglobulinemia (IgM)
- Polyclonal gammopathy (multiple Igs (chronic infections, autoimmune, etc))
Canine ImmunoDeficiency Disorders
result from the absence or failure of normal function in the innate and/or adaptive immune systems
primary canine immunodeficiency disorder
due to intrinsic defects in the cells or their products, typically genetic (rare in dogs)
secondary canine immunodeficiency disorder
acquired as a consequence of some disease process like again, neoplasia, disease, FPT, etc
Cutoff for Canine IgG levels
less than 700mg/100ml is deficient
Cutoff for Canine IgM levels
less than 75mg/100ml is deficient
Cutoff for Canine IgA levels
less than 40mg/100ml is deficient
What if the foal is over 18 hours old?
IgG will have to be given intravenously
What type HST reaction do you get acutely if wrong blood transfusion given?
Type 2
major crossmatch
detect Ab in the recipient serum against donor erythrocytes
minor crossmatch
test donor plasma with recipient RBC (can remove the plasma)
Hemolytic Disease of the Newborn
fetal RBC leak into maternal circulation, mom develops Abs against these RBCs, then when the foal ingests colostrum and the ingested Ab cause RBC destruction
Direct Coomb’s Test
used to detect RBCs that already have antibody attached to them; add Coomb’s reagent (anti IgG) directly to blood sample
used for patients already in hemolytic crisis
