Immunology Flashcards

Question

attenuated

Answer 1

(weakened but still alive). Attenuated vaccines normally cause a longer-lasting and more potent immune response. In very rare cases, they have caused the disease

Answer 2

(killed) Generally safer and have less ability to cause disease, although vaccine-associated sarcomas in cats have been an issue.

Answer 3

Involve the direct introduction into the body tissues of a sequence of DNA representing an antigen to which an immune system response is desired. Attenuated vaccines normally cause a longer-lasting and more potent immune response. Inactivated vaccines are generally safer and have less ability to cause disease, although vaccine-associated sarcomas in cats have been an issue.

Answer 4

Immunoassays require which samples? Serum What is the most practical method of collection? Vacutainer system How long is the clot allowed to sit on the blood sample? 20 to 30 minutes At what speed and for how long do you centrifuge a serum sample? 1500 rpm for 10 minutes What can be done if there is little serum that has separated? “Rimming” the tube with a wooden applicator stick to loosen the clot Can serum and plasma be frozen? Yes

Answer 5

Ability to correctly identify all animals that are truly positive for a given reaction procedure (how much protein (antigen/antibody) needs to be present for the test to show positive)

Answer 6

Measures the number of false positives produced with a given reaction procedure (are there any other antigens/antibodies that have cross-reactivity because they are so similar)

Answer 7

Accurate way to detect antigen in the body OR antibodies in serum ANTIGEN test contains monoclonal antibodies ANTIBODY test contains the antigen IF antigen-antibody complexes form - color change = positive

Answer 8

Equine Infectious Anemia (EIA) test ANTIGEN test only The more antigen present, the more color change you’ll see

Answer 9

Bovine brucellosis If serum contains corresponding antibody, the formation of antibody-antigen complexes causes agglutination If no antibody is present , the mixture of latex and serum will remain evenly dispersed

Answer 10

Similar to ELISA that if antigen-antibody complexes form, you see a color change Heartworm and other tests Different from ELISA - no diluent needed - just the sample Instead of an (only an) enzyme, the method of color change is either: Colloidal gold Enzyme Agglutinated latex particles As antigen-antibody complexes pass over, the color changes

Answer 11

A mismatched transfusion given to an animal results in antibodies forming against the RBC antigen in the transfused sample.

Answer 12

The specific red blood cell markers in an individual animal

Answer 13

Neonatal isoerythrolysis can occur in type A or AB kittens if the queen is type B. If breeding a type A cat with a B queen, is it important to test blood types, and A and AB kittens will have to be bottle fed if the queen is type B.

Answer 14

DEA 1 and DEA 7

Answer 15

If a DEA-1.1- dog has previously received a transfusion from a DEA-1.1+ dog and receives another a severe reaction can occur. This is because mismatched DEA-1 elicits the greatest antigen response of all DEA types

Answer 16

A blood – Found in the majority of cats in the U.S.; Have weak anti-B antibodies. B blood – Found in certain purebred breeds; Have strong anti-A antibodies. AB blood – Few cats have this blood type.

Answer 17

Type A and type AB kittens have naturally occuring anti-A antibodies from type B queen

Answer 18

Transfusion reactions are commonly fatal

Answer 19

Test that detects the presence of antibodies in mare serum (or colostrum) to foal erythrocytes to confirm or prevent neonatal isoerythrolysis.

Answer 20

Requires many steps Use whole blood sample (EDTA, heparin, or acid-citrate-dextrose) Needs antibodies for each type of potential reaction Observed macro/microscopically for evidence of hemolysis or agglutination Brief description - Centrifuge blood; remove plasma and buffy coat; wash RBCs 3x in saline solution, centrifuge, resuspend; distribute RBC suspension into as many tubes needed for the number of blood type antisera being tested; Add 0.1mL antisera into tube; Incubate tubes (15 min room temp); Centrifuge (15 sec, 1000 g); Examine micro/macroscopically

Answer 21

Available for many species; rapid, accurate Uses whole blood sample (EDTA) Tests DEA 1 +/-, or A, B, and AB (no mixing patient/recipient)

Answer 22

color change for antigen type

Answer 23

Mix 2 samples together for compatibility Major - Serum from recipient is added to RBCs from donor Minor - Serum from donor is added to RBCs from recipient

Answer 24

Grade 0: No evidence of agglutination or hemolysis Grade 1: Many small agglutinates and some free cells Grade 2: Large agglutinates and smaller clumps of cells Grade 3: Many large agglutinates Grade 4: Solid aggregate of cells

Answer 25

Allergens – Substance that causes an allergic reaction Urticaria – Hives Wheals – Swelling on the surface of the skin - red welts. Angioedema – Edema of the dermis and subcutaneous tissues

Answer 26

IgE, basophils, and mast cells

Answer 27

Hair is shaved on the lateral thorax - 2cm spacing use felt-tip marker to mark injection sites - 26g needle to inject 0.05mL of specifically selected antigens (based on patient Hx and location) - evaluate sites at 15 and 30 minutes Positive control: histamine Negative control: saline

Answer 28

Positive reaction? A raised welt that indicates the animal is allergic to the antigen Hypersensitivity reactions? Why? Urticaria (hives), wheals, or angioedema may be present if the dog has allergies to more than one allergen

Answer 29

- Subq injections - Too little allergen - Drug interference (glucocorticoids, antihistamines, tranquilizers, progestational compounds, any drugs that lower blood pressure) - Anergy (testing during peak hypersensitivity reaction) - Inherent host factors - Endoparasitism or ectoparasitism - Off-season testing (testing more than 1-2 months after clinical signs have disappeared - Histamine “hyporeactivity”

Answer 30

- Irritant test allergens (especially those that contain glycerin; house dust, feathers, wool, old, and all food preparations) - Contaminated test allergens (bacteria; fungi) - Skin-sensitizing antibody only - Poor technique (traumatic placement of the needle, dull or burred needle, too large a volume injected, air injected) - Substances that cause nonimmunologic histamine release (narcotics) - ”Irritable” skin (large reactions seen to all infected substances) - Dermatographism - Mitogenic allergen

Answer 31

An ELISA test for the determination of allergen specific IgE antibodies in dogs, cats, and horses. Tests for grasses, trees, weeds, mites, insects, and fungi

Answer 32

Inject tuberculin intradermally at a site in the cervical region or skin fold at the base of the tail in large animals.

Answer 33

A delayed local inflammatory reaction is observed if the animal has been exposed to Mycobacterium. It is a delayed reaction because the T lymphocytes must migrate to the foreign antigen injected

Answer 34

Detects the presence of autoantibodies (antibodies against the body) - IMHA Direct Coombs test – Detects antibodies that attack RBCs Positive test? Immune-mediated hemolytic disease Indirect Coombs Testing – Detects antibodies that are already attached to red blood cells

Answer 35

Antigen in test kit and patient serum are placed in separate wells on a agar plate Sample used – Serum Band of precipitation? Diffusion of antigen and serum through agar plate No band? No antibody present

Answer 36

Similar to CELISA but a radioisotope is used in place of the enzyme Most Similar to? CELISA technique Sample used – Serum Patient antigen vs. labeled antigen. How do they affect the other? With increasing amounts of patient antigen, more labeled antigen is displaced from the antibody Measure remaining radioactivity amount – Measured and compared with a standard curve to determine the concentration of antigen in the patient’s serum

Answer 37

IFA - Fluorescent Antibody Testing - detect the presence of a specific antibody in a sample Direct antibody testing – Patient sample is added to a slide that has been precoated with a fluorescent dye conjugated antigen. Slide is examined with a microscope Dye? Fluorescent dye IFA testing – The patient sample is incubated on a slide that contains a specific test antigen. The slide is then washed to remove any unbound antibody. Fluorescent-labeled antibody is added to the system, and the slide is microscopically examined

Answer 38

Describe the test –Antibody titers are performed to differentiate active infection from prior exposure and to evaluate the need for revaccination. The test is performed by making serial dilutions of each sample. Each dilution is then examined for the presence of the antibody. The reciprocal of the greatest dilution that still elicits a positive test result is the titer Distinguishes between? Active infection and prior exposure to certain antigens High titer means –Often indicates active infection Low Titer means –Usually indicates previous exposure to the specific antigen

Answer 39

Advantages of molecular diagnostics: Increased sensitivity and specificity, many factors that influence other procedures are not as crucial, and they have faster turnaround times Disadvantages of molecular diagnostics: Contamination that leads to false positive results, the high level of expertise needed to run the tests, the need for more than one room in which to perform tests, and high costs Reverse transcriptase polymerase chain reaction: Similar to PCR, but the single-stranded RNA must first be converted to a double-stranded DNA before the PCR process can continue Real-time polymerase chain reaction: Decreases the risk of contamination.More easily automated and is faster to run.

Answer 40

Amplification: PCR is called an amplification assay because a small amount of a DNA segment detected in the sample is amplified to run the test better and to determine the results. Consists of 3 basic steps: Denaturation: The sample is heated to break apart the double-stranded DNA molecule into two separate strands. Each strand serves as a template to which new nucleotides will attach. Annealing The temperature is lowered to cause the primers to bind (anneal) to the separated strands. Primers mark the beginning and the end of the section of DNA to be copied. This will only happen if DNA is present in the sample that is complementary to the primers. Extension: The temperature is raised once more, and the Taq DNA polymerase (the enzyme that can read the DNA code and assemble the nucleotide bases to form new complementary strands) causes new DNA segments to be produced (extended).

Answer 41

Immediate hypersensitivity, occurs when mast cells release chemical mediators. Atopy- Allergies Anaphylactic Shock- Severe reaction to antigens in circulation

Answer 42

Antibodies are directed against animals own cells (Antibody-mediated diseases) Immune mediated hemolytic anemia (IMHA)- Causes red blood cell destruction by the host.

Answer 43

Occurs when antibodies and antigens form complexes deposited in various blood vessels. Immune complex disease- Example: Glomerulonephritis caused by antibody-antigen deposits in the kidney.

Answer 44

T-cell mediated disease caused by the reaction of T lymphocytes against self-antigens in tissues.

Answer 45

Tumor characterized by the uncontrolled growth of lymphocytes.