MCQAHG

Question 1

1. A description of the antiglobulin test is:
   a. IgG and C3d are required for RBC sensitization.
   b. Human globulin is completely eluted from RBCs
   during saline washings.
   c. Human globulin is injected into an animal.
   d. AHG reacts with human globulin molecules bound to
   RBCs.

Question 2

2. Polyspecific AHG reagent contains:
   a. Anti-IgG and anti-IgA.
   b. Anti-IgG and anti-IgM.
   c. Anti-IgG and anti-C3d.
   d. Anti-IgA and Anti-C3d

Question 3

3. Monoclonal anti-C3d is:
   a. Derived from one clone of plasma cells.
   b. Derived from multiple clones of plasma cells.
   c. Derived from immunization of rabbits.
   d. Reactive with C3b and C3d.

Question 4

4. Which of the following is a clinically significant
   antibody whose detection has been reported in some
   instances to be dependent on anticomplement activity in polyspecific AHG?
   a. Anti-Jka
   b. Anti-Lea
   c. Anti-P1
   d. Anti-H

Question 5

5. After the addition of IgG-coated RBCs (check cells)
   to a negative AHG reaction during an antibody
   screen, a negative result is observed. Which of the
   following is a correct interpretation based on these
   findings?
   a. The antibody screen is negative.
   b. The antibody screen cannot be interpreted.
   c. The saline washings were adequate.
   d. AHG reagent was added.

Question 6

6. RBCs must be washed in saline at least three times
   before the addition of AHG reagent to:
   a. Wash away any hemolyzed cells.
   b. Remove traces of free serum globulins.
   c. Neutralize any excess AHG reagent.
   d. Increase the antibody binding to antigen

Question 7

7. An in vivo phenomenon associated with a positive
   DAT is:
   a. Passive anti-D detected in the maternal sample.
   b. Positive antibody screen tested by LISS.
   c. Identification of alloantibody specificity using a
   panel of reagent RBCs.
   d. Maternal antibody coating fetal RBCs.

Question 8

8. False-positive DAT results are most often associated
   with:
   a. Use of refrigerated, clotted blood samples in which
   complement components coat RBCs in vitro.
   b. A recipient of a recent transfusion manifesting an
   immune response to recently transfused RBCs.
   c. Presence of antispecies antibodies from administration of immune globulin (IVIG).
   d. A positive autocontrol caused by polyagglutination.

Question 9

9. Polyethylene glycol (PEG) enhances antigenantibody reactions by:
   a. Decreasing zeta potential.
   b. Concentrating antibody by removing water.
   c. Increasing antibody affinity for antigen.
   d. Increasing antibody specificity for antigen.

Question 10

10. Solid-phase antibody screening is based on:
    a. Adherence.
    b. Agglutination.
    c. Hemolysis.
    d. Precipitation.

Question 11

11. A positive DAT may be found in which of the following
situations?
a. A weak D-positive patient
b. A patient with anti-M
c. HDFN
d. An incompatible crossmatch

Question 12

12. What do Coombs’ check cells consist of?
    a. Type A-positive cells coated with anti-IgG
    b. Type A-negative cells coated with anti-IgG
    c. Type O-positive cells coated with anti-D
    d. Type B-negative cells coated with anti-D

Question 13

13. Which of the following IAT methods requires the use of
check cells?
a. Manual tube method with albumin 
b. Gel
c. Automated solid-phase analyzer
d. Enzyme-linked

Question 14

14. Which uncontrollable factor can affect AHG testing?
    a. Temperature
    b. Antibody affinity
    c. Gravitational force in the centrifuge
    d. Incubation time

Question 15

15. Which would be the most efficient method for a laboratory staffed by medical laboratory technicians?
    a. LISS
    b. Polybrene
    c. Solid-phase or gel
    d. Enzyme-linked

Question 16

16. A 27-year-old group O mother has just given birth to a
    group A baby. Since the mother has IgG anti-A, anti-B
    and anti-A, B in her plasma, which of the following
    methods and tests would be most effective at detecting
    the anti-A on the baby’s RBCs?
    a. DAT using common tube technique
    b. DAT using gel
    c. IAT using common tube technique
    d. IAT using gel

Question 17

1. A principle of the antiglobulin test is:
   a. IgG and C3d are required for RBC sensitization.
   b. Human globulin is eluted from RBCs during saline
   washings.
   c. Injection of human globulin into an animal engenders
   passive immunity.
   d. AHG reacts with human globulin molecules bound to
   RBCs or free in serum.

Question 18

2. Polyspecific AHG reagent contains:
   a. Anti-IgG.
   b. Anti-IgG and anti-IgM.
   c. Anti-IgG and anti-C3d.
   d. Anti-C3d.

Question 19

3. Monoclonal anti-C3d is:
   a. Derived from one clone of plasma cells.
   b. Derived from multiple clones of plasma cells.
   c. Derived from immunization of rabbits.
   d. Reactive with C3b and C3d.

Question 20

4. Which of the following is a clinically significant antibody
   whose detection has been reported in some instances to
   be dependent on anticomplement activity in polyspecific
   AHG?
   a. Anti-Jka
   b. Anti-Lea
   c. Anti-P1
   d. Anti-H

Question 21

5. After the addition of IgG-coated RBCs (check cells) to a
   negative AHG reaction during an antibody screen, a
   negative result is observed. Which of the following is a
   correct interpretation?
   a. The antibody screen is negative.
   b. The antibody screen needs to be repeated.
   c. The saline washings were adequate.
   d. Reactive AHG reagent was added.

Question 22

6. RBCs must be washed in saline at least three times before
   the addition of AHG reagent to:
   a. Wash away any hemolyzed cells
   b. Remove traces of free serum globulins
   c. Neutralize any excess AHG reagent
   d. Increase the antibody binding to antigen

Question 23

7. An in vitro phenomenon associated with a positive
   IAT is:
   a. Maternal antibody coating fetal RBCs
   b. Patient antibody coating patient RBCs
   c. Recipient antibody coating transfused donor RBCs
   d. Identification of alloantibody specificity using a panel
   of reagent RBCs

Question 24

8. False-positive DAT results are most often associated with:
   a. Use of refrigerated, clotted blood samples in which
   complement components coat RBCs in vitro.
   b. A recipient of a recent transfusion manifesting an
   immune response to recently transfused RBCs.
   c. Presence of heterophile antibodies from administration of globulin.
   d. A positive autocontrol caused by polyagglutination

Question 25

9. Polyethylene glycol enhances antigen-antibody reactions by: a. Decreasing zeta potential. b. Concentrating antibody by removing water. c. Increasing antibody affinity for antigen. d. Increasing antibody specificity for antigen

Question 26

10. Solid-phase antibody screening is based on: a. Adherence. b. Agglutination. c. Hemolysis. d. Precipitation.

Question 27

``` 11. A positive DAT may be found in which of the following situations? a. A weak D-positive patient b. A patient with anti-K c. HDN d. An incompatible crossmatch ```

Question 28

12. What do Coombs’ control cells consist of? a. Type A-positive cells coated with anti-D b. Type A-negative cells coated with anti-D c. Type O-positive cells coated with anti-D d. Type O-negative cells coated with anti-D

Question 29

``` 13. Which of the following methods requires the use of check cells? a. LISS b. Gel c. Solid-phase d. Enzyme-linked ```

Question 30

``` 14. Which factor can affect AHG testing, yet is uncontrollable in the lab? a. Temperature b. Antibody affinity c. Gravitational force in the centrifuge d. Incubation time ```

Question 31

15. If you had the authority to decide which primary AHG methodology to utilize at your lab, which method would you choose based on the knowledge that the majority of the staff are generalists? a. LISS b. Polybrene c. Solid phase or gel d. Enzyme-linked

Question 32

16. A 27-year-old group O mother has just given birth to a beautiful, group A baby girl. Since the mother has IgG anti-A in her plasma, it is likely that the baby is experiencing some in vivo red cell destruction. Which of the following methods and tests would be most effective at detecting the anti-A on the baby’s RBCs? a. DAT using common tube technique b. DAT using gel c. IAT using common tube technique d. IAT using gel

Question 33

The _______ is used to detect RBCs sensitized | by IgG alloantibodies, IgG autoantibodies, and complement components.

Answer 33

antiglobulin test

Question 34

AHG reagents containing ______ are needed for the detection of IgG antibodies because the IgG monomeric structure is too small to directly agglutinate sensitized RBCs.

Answer 34

anti-IgG

Question 35

_______ contain antibodies to human IgG and the C3d component of human complement.

Answer 35

Polyspecific AHG sera

Question 36

________ contain only one antibody specificity: either anti-IgG or antibody to anti–C3b-C3d.

Answer 36

Monospecific AHG sera

Question 37

_______are prepared by injecting human globulins into rabbits, and an immune stimulus triggers production of antibody to human serum.

Answer 37

Classic AHG sera (polyclonal)

Question 38

______ is used to produce monoclonal antiglobulin serum.

Answer 38

Hybridoma technology

Question 39

The DAT detects in vivo sensitization of RBCs with IgG or complement components. Clinical conditions that can result in a positive DAT include ______

Answer 39

HDN, HTR, and AIHA.

Question 40

The DAT detects in_____sensitization of RBCs with _____. Clinical conditions that can result in a positive DAT include HDN, HTR, and AIHA.

Answer 40

vivo | IgG or complement components

Question 41

The _____ detects in vitro sensitization of RBCs and can be applied to compatibility testing, antibody screen, antibody identification, RBC phenotyping, and titration studies

Answer 41

IAT

Question 42

The IAT detects in ____ sensitization of RBCs and can be applied to compatibility testing, antibody screen, antibody identification, RBC phenotyping, and titration studies

Answer 42

vitro

Question 43

A _____ is followed by a DAT panel using monospecific anti-IgG and anti-C3d to determine the specific type of protein sensitizing the RBC.

Answer 43

positive DAT

Question 44

_____ should be used to collect blood samples for the DAT to avoid in vitro complement attachment associated with refrigerated clotted specimens

Answer 44

EDTA

Question 45

EDTA should be used to collect blood samples for the ____ to avoid in vitro complement attachment associated with refrigerated clotted specimens

Answer 45

DAT

Question 46

There are multiple sources or error that can be introduced into the AHG procedure.

Question 47

________ can all be used as enhancement media for AHG testing, with each having their own advantages and disadvantages.

Answer 47

LISS, PEG, polybrene, and albumin

Question 48

___,_____,____,______ are available methods to use in AHG testing.

Answer 48

Conventional tube testing, gel technology, enzyme linked technology, and solid-phase testing

Question 49

Method-dependent antibodies do exist and should be | evaluated on a case-by-case basis.