Immunology Lab Final Material

Question 1

3 Ways to Look at Failure of Passive Transfer in foals

Answer 1

1. Refractometry
2. ELISA
3. Radial Immunodiffusion (RID)

Question 2

factors to decide what test

Answer 2

sensitivity, specificity, time frame for results, ease of use, cost

Question 3

Refractometry

Answer 3

measure of refractive index of a sample

Question 4

what are we measuring directly with a refractometer?

Answer 4

refractive index

Question 5

what are we measuring indirectly with a refractometer?

Answer 5

total protein content of serum

Question 6

refractive index

Answer 6

relative velocity of light of light in a medium compared to through the air (higher the number, the slower it moves)

Question 7

SNAP Foal IgG test

Answer 7

ELISA, AB specific for equine IgG already bound to test, whole blood added on sample spot, then conjugate (peroxidase labeled anti-equine IgG)

Question 8

how to read a snap foal test

Answer 8

color relative to <400 and >800 mg/dl ranges

Question 9

which test gives the most precise levels?

Answer 9

radioimmunodiffusion (RID)

Question 10

Radioimmunodiffusion

Answer 10

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

Question 11

canine immunoproliferative disorders

Answer 11

abnormal proliferation of Ig-producing cells and an excess of Ig

Question 12

3 types of canine immunoproliferative disorders

Answer 12

1. multiple myeloma (a monoclonal gammopathy, proliferation of plasma cells)
2. macroglobulinemia (IgM)
3. Polyclonal gammopathy (multiple Igs (chronic infections, autoimmune, etc))

Question 13

Canine ImmunoDeficiency Disorders

Answer 13

result from the absence or failure of normal function in the innate and/or adaptive immune systems

Question 14

primary canine immunodeficiency disorder

Answer 14

due to intrinsic defects in the cells or their products, typically genetic (rare in dogs)

Question 15

secondary canine immunodeficiency disorder

Answer 15

acquired as a consequence of some disease process like again, neoplasia, disease, FPT, etc

Question 16

Cutoff for Canine IgG levels

Answer 16

less than 700mg/100ml is deficient

Question 17

Cutoff for Canine IgM levels

Answer 17

less than 75mg/100ml is deficient

Question 18

Cutoff for Canine IgA levels

Answer 18

less than 40mg/100ml is deficient

Question 19

What if the foal is over 18 hours old?

Answer 19

IgG will have to be given intravenously

Question 20

What type HST reaction do you get acutely if wrong blood transfusion given?

Answer 20

Type 2

Question 21

major crossmatch

Answer 21

detect Ab in the recipient serum against donor erythrocytes

Question 22

minor crossmatch

Answer 22

test donor plasma with recipient RBC (can remove the plasma)

Question 23

Hemolytic Disease of the Newborn

Answer 23

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

Question 24

Direct Coomb’s Test

Answer 24

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

Question 25

Indirect Coomb’s Test

Answer 25

detects presence of Ig that is specific for RBC antigens (take recipient blood and mix with serum/colostrum from donor, THEN add Coomb’s reagent)

Question 26

atopy

Answer 26

allergic reaction

Question 27

allergen

Answer 27

type of antigen which produces an abnormally vigorous immune threat

Question 28

Main clinical sign of allergies?

Answer 28

pruritis (itchy!)

Question 29

Do serology IgE tests tell you what an animal is allergic to?

Answer 29

no, only that they’ve been exposed to that antigen sometime in their life

Question 30

Intradermal skin test

Answer 30

evaluates antigen-specific IgE bound to mast cells

Question 31

What should always be addressed first before pursuing allergy testing?

Answer 31

ectoparasite treatment

Question 32

positive control for IDST

Answer 32

histamine

Question 33

negative control for IDST

Answer 33

saline

Question 34

Most common allergen?

Answer 34

dust mites!

Question 35

Reasons for positive IDST reactions

Answer 35

-patient allergic
-patient allergic to a cross-reacting antigen
-irritant was too concentrated
-large volume injected

Question 36

Reasons for negative IDST reactions

Answer 36

-patient not allergic
-SQ injection (instead of intradermal)
-insufficient antigen
-patient is on drugs and not enough withdrawal time, affecting the reaction