Deck 3: Blood Banking Reagents: Overview and Applications

Question 1

Why is incubation omitted in the direct antihuman globulin test?

A) The direct antiglobulin test can be used in an emergency to replace the indirect test.
B) Incubation will cause hemolysis.
C) The antigen-antibody complex has already formed in vivo.
D) IgM antibodies are detected in the direct antiglobulin test.

Answer 1

C
Incubation of the antigen-antibody complex essentially has taken place within the patient (or donor),making additional incubation in the tube unnecessary.

Question 2

What temperature is used for incubation in the indirect antihuman globulin test?

A) 22° C
B) 37° C
C) 4° C
D) 56° C

Answer 2

B
Incubation takes place at body temperature,which is 37° C.

Question 3

Reagent antibodies prepared from human sources are:

A) unsafe.
B) too low in potency to be effective.
C) polyclonal in specificity.
D) preferred because of their lower cost.

Answer 3

C
Human-derived antisera have antibodies to multiple specificities and meet Food and Drug Administration guidelines for potency and safety.

Question 4

What method displays a positive reaction as a compact red cell button?

A) Gel test
B) Microtiter plate
C) Solid-phase red cell adherence
D) Molecular testing

Question 5

Select the test that uses IgG-sensitized red cells (check cells).

A) Antiglobulin test
B) D-antigen typing
C) Rh-antigen typing
D) B-antigen detection

Question 6

The antiglobulin test was performed using gel technology.A button of cells was observed at the bottom of the microtube following centrifugation.How do you interpret this result?

A) There is a problem with the card.
B) The result is a negative reaction.
C) The result is a strong positive reaction.
D) The test was not washed correctly.

Question 7

Following centrifugation of the gel card,red cells are evenly dispersed throughout one of the microtubes.This reaction could be graded as a:

A) 4+.
B) 3+.
C) 2+.
D) 1+.

Question 8

Where are product limitations and technical considerations for each reagent located?

A) Standard operating procedure
B) Product insert
C) Food and Drug Administration code of regulations
D) AABB standards

Question 9

Which red cells are used to screen for antibodies in donor samples?

A) Screening cells (two vials)
B) Pooled screening cells
C) Panel cells
D) Screening cells (three vials)

Question 10

Which of the following is not an advantage of using a monoclonal antibody over a polyclonal antibody?

A) There are very few variations between lots.
B) There are no contaminating antibodies.
C) Direct agglutination is usually faster.
D) All variations of the antigen can be detected.

Question 11

Select the method that uses a dextran-acrylamide matrix.

A) Solid-phase red cell adherence
B) Microplate
C) Gel technology
D) Tube techniques

Question 12

Which of the following statements is true regarding high-protein anti-D reagents?

A) They have been largely replaced with low-protein monoclonal reagents.
B) They contain high concentrations of bovine albumin.
C) They may increase the possibility of a false-positive reaction, requiring the use of a control.
D) All of the above are true.

Question 13

What specificities does polyspecific antihuman globulin contain?

A) Anti-IgG.
B) Anti-C3b and anti-C3d.
C) Anti-IgG and anti-C3d.
D) Anti-IgG and anti-IgM.

Question 14

How would you interpret the results if both the anti-D reagent and the Rh control were 2+ agglutination reactions?

A) D-positive
B) D-negative
C) Unable to determine without further testing
D) Depends on whether the sample was from a patient or a blood donor

Question 15

What reagent contains antibodies to multiple antigenic epitopes?

A) Polyclonal-based
B) Monoclonal-based
C) Heterophile antibody-based
D) Alloantibody-based

Question 16

In the solid-phase red cell adherence test,how does a negative test appear?

A) A button of cells on the bottom of the well
B) Adherence of cells along the sides and bottom of the wells
C) Hemolysis of red cells
D) A line of cells along the top of the well

Question 17

Which of the following statements is true regarding IgG-sensitized red cells?

A) They must be used to confirm a negative antiglobulin tube test.
B) They must be used to confirm a positive antiglobulin test.
C) They must be used to confirm a direct antiglobulin test that was negative with anti-C3d.
D) They should be used only with the indirect antiglobulin test.

Question 18

Which of the following items provides evidence for reagent red cell deterioration?

A) Spontaneous agglutination
B) Significant hemolysis
C) Loss of agglutination strength over time
D) All of the above

Question 19

Monoclonal antibodies are prepared in:

A) vitro.
B) vivo.
C) laboratory animals.
D) humans.

Question 20

Solid-phase red cell adherence used for antibody detection has an advantage over tube testing because:

A) there is no washing involved.
B) incubation time is not necessary.
C) the endpoint is more clearly defined.
D) indicator cells (IgG-coated cells) are not necessary.

Question 21

Select the antiglobulin test that best fits the descriptions below.A selection may be used more than once.
a.Indirect antiglobulin test
b.Direct antiglobulin test
c.Both the direct and indirect antiglobulin test
Requires washing the cells several times before the addition of antihuman globulin reagent

Question 22

MATCHING
Select the reagent from the list below and match it to the routine blood banking procedure.
a.Panel cells
b.Screening cells
c.A1 and B cells
d.ABO antisera
e.Lectins
Reagent used to detect the presence of red cell antibodies

Question 23

Select the antiglobulin test that best fits the descriptions below.A selection may be used more than once.
a.Indirect antiglobulin test
b.Direct antiglobulin test
c.Both the direct and indirect antiglobulin test
Detects IgG or complement-coated red cells

Question 24

What immunoglobulin class reacts best by antiglobulin testing?

A) IgM
B) IgA
C) IgE
D) IgG

Question 25

Why is polyethylene glycol reagent added to the screen or panel?

A) Enhance detection of IgM antibodies.
B) Eliminate the reactivity of certain antigens.
C) Increase the avidity of IgG antibodies.
D) Eliminate the need for washing in the indirect antiglobulin test.

Question 26

Which of the following red cell antigens do proteolytic enzymes destroy?

A) Rh system antigens
B) Antigens Fyᵃ and Fyᵇ in the Duffy system
C) Antigens in the Kidd system
D) Lewis system antigens

Question 27

What is the purpose of adding antibody-sensitized red cells following the antiglobulin test?

A) Ensure a weak antibody reaction was not missed
B) Confirm positive reactions
C) Check that the wash procedure was sufficient to remove unbound antibodies
D) Check that sufficient incubation took place

Question 28

Select the antiglobulin test that best fits the descriptions below.A selection may be used more than once.
a.Indirect antiglobulin test
b.Direct antiglobulin test
c.Both the direct and indirect antiglobulin test
Incubation step is not necessary

Question 29

MATCHING
Select the reagent from the list below and match it to the routine blood banking procedure.
a.Panel cells
b.Screening cells
c.A1 and B cells
d.ABO antisera
e.Lectins
Reagent derived from plants used to distinguish group A₁ from group A₂ red cells

Question 30

Rouleaux is a false-positive reaction caused by elevated serum protein levels.Which of the following tests would not likely be affected by an elevated protein level?

A) Immediate-spin antibody screen
B) Direct antiglobulin test
C) Reverse typing in the ABO test
D) ABO forward typing

Question 31

Select the antiglobulin test that best fits the descriptions below.A selection may be used more than once.
a.Indirect antiglobulin test
b.Direct antiglobulin test
c.Both the direct and indirect antiglobulin test
Tests for certain clinical conditions such as hemolytic disease of the newborn and autoimmune hemolytic anemia

Question 32

MATCHING
Select the reagent from the list below and match it to the routine blood banking procedure.
a.Panel cells
b.Screening cells
c.A1 and B cells
d.ABO antisera
e.Lectins
Reagent used in the identification of ABO antibodies

Question 33

MATCHING
Select the reagent from the list below and match it to the routine blood banking procedure.
a.Panel cells
b.Screening cells
c.A1 and B cells
d.ABO antisera
e.Lectins
Reagent used to determine the ABO antigenic composition of a patient's red cells

Question 34

MATCHING
Select the reagent from the list below and match it to the routine blood banking procedure.
a.Panel cells
b.Screening cells
c.A1 and B cells
d.ABO antisera
e.Lectins
Reagent used to identify the specificity of a red cell antibody